End effector comprising an anvil including projections extending therefrom

BACKGROUND

0001The present invention relates to stapling instruments and, to a surgical stapling instrument for producing one or more rows of staples.

0002A stapling instrument can include a pair of cooperating elongate jaw members, wherein each jaw member can be adapted to be inserted into a patient and positioned relative to tissue that is to be stapled and/or incised. One of the jaw members can support a staple cartridge with at least two laterally spaced rows of staples contained therein, and the other jaw member can support an anvil with staple-forming pockets aligned with the rows of staples in the staple cartridge. Generally, the stapling instrument can further include a pusher bar and a knife blade which are slidable relative to the jaw members to sequentially eject the staples from the staple cartridge via camming surfaces on the pusher bar and/or camming surfaces on a wedge sled that is pushed by the pusher bar. The camming surfaces are configured to activate a plurality of staple drivers carried by the cartridge and associated with the staples in order to push the staples against the anvil and form laterally spaced rows of deformed staples in the tissue gripped between the jaw members. The knife blade can trail the camming surfaces and cut the tissue along a line between the staple rows. Examples of such stapling instruments are disclosed in <patcit id="pcit0001" dnum="US7794475B"><text>U.S. Patent No. 7,794,475</text></patcit>.

0003<patcit id="pcit0002" dnum="US5452837A"><text>US 5452837 A</text></patcit> discloses a surgical stapler with a tissue gripping ridge on at least one of the tissue contacting surfaces. The ridge has serrated surfaces which mesh when in contact with each other to hold tissue.

0004<patcit id="pcit0003" dnum="WO2012050798A1"><text>WO 2012/050798 A1</text></patcit> discloses a staple cartridge wherein the cartridge body comprises a tissue-contacting deck and a plurality of ridges extending from the tissue-contacting deck. The ridges are configured to prevent, or reduce the possibility of, tissue from moving relative to the staple cartridge during use.

0005<patcit id="pcit0004" dnum="EP1917918A2"><text>EP 1 917918 A2</text></patcit> discloses a surgical stapler that includes a staple cartridge and an anvil member. The staple cartridge includes surgical fasteners disposed in rows of retention slots. The tissue contacting surface of the staple cartridge is tapered or stepped and the tissue contacting surface of the anvil member complements the tissue contacting surface of the staple cartridge.

BRIEF DESCRIPTION OF THE DRAWINGS

0006Various exemplary embodiments described herein, both as to organization and methods of operation, together with their advantages, may be understood in accordance with the following description taken in conjunction with the accompanying drawings as follows: <ul id="ul0001" list-style="none" compact="compact"><li><figref idref="f0001">FIG. 1</figref> is an elevational view of a surgical stapling instrument;</li><li><figref idref="f0001">FIG. 2</figref> is a cross-sectional view of an end effector of the surgical stapling instrument of <figref idref="f0001">FIG. 1</figref> taken along line 2-2 in <figref idref="f0001">FIG. 1</figref>;</li><li><figref idref="f0002">FIG. 3</figref> is a cross-sectional perspective view of the end effector of <figref idref="f0001">FIG. 1</figref>;</li><li><figref idref="f0003">FIG. 4</figref> is a cross-sectional view of the end effector of <figref idref="f0001">FIG. 1</figref> illustrating staples contained therein in an unfired configuration;</li><li><figref idref="f0004">FIG. 5</figref> is a diagram illustrating the staples of <figref idref="f0003">FIG. 4</figref> in a fired configuration;</li><li><figref idref="f0005">FIG. 6</figref> is a diagram illustrating the end effector of <figref idref="f0001">FIG. 1</figref> being used to staple and transect tissue;</li><li><figref idref="f0006">FIG. 7</figref> is a perspective view of a staple cartridge in accordance with at least one embodiment comprising a plurality of ridges extending from a cartridge body;</li><li><figref idref="f0007">FIG. 8</figref> is a detail view of the staple cartridge of <figref idref="f0006">FIG. 7</figref>;</li><li><figref idref="f0008">FIG. 8A</figref> is a cross-sectional view of the staple cartridge of <figref idref="f0006">FIG. 7</figref>;</li><li><figref idref="f0009">FIG. 9</figref> is a detail view illustrating staples positioned within staple cavities defined in the staple cartridge of <figref idref="f0006">FIG. 7</figref>;</li><li><figref idref="f0010">FIG. 10</figref> is a partial perspective view of a staple cartridge in accordance with at least one alternative embodiment comprising a plurality of transverse ridges extending from a cartridge body;</li><li><figref idref="f0011">FIG. 11</figref> is a partial perspective view of a staple cartridge in accordance with at least one alternative embodiment comprising a plurality of transverse ridges extending from a cartridge body;</li><li><figref idref="f0012">FIG. 12</figref> is a partial perspective view of a staple cartridge in accordance with at least one alternative embodiment comprising a plurality of ridges surrounding the proximal and distal ends of staple cavity openings defined in a cartridge body;</li><li><figref idref="f0013">FIG. 13</figref> is a partial perspective view of a staple cartridge in accordance with at least one alternative embodiment comprising a plurality of ridges surrounding the proximal and distal ends of staple cavity openings defined in a cartridge body;</li><li><figref idref="f0014">FIG. 14</figref> is a partial perspective view of a staple cartridge in accordance with at least one alternative embodiment comprising a plurality of knurled ridges extending from a cartridge body;</li><li><figref idref="f0015">FIG. 15</figref> is a partial perspective view of a staple cartridge in accordance with at least one alternative embodiment comprising a plurality of knurled ridges extending from a cartridge body;</li><li><figref idref="f0016">FIG. 15A</figref> is a perspective view of a pyramidal knurl in accordance with at least one embodiment;</li><li><figref idref="f0016">FIG. 15B</figref> is a perspective view of a frustoconical knurl in accordance with at least one embodiment;</li><li><figref idref="f0016">FIG. 15C</figref> is a perspective view of a triangular knurl in accordance with at least one embodiment;</li><li><figref idref="f0017">FIG. 16</figref> is a partial perspective view of a staple cartridge in accordance with at least one alternative embodiment comprising a plurality of ridges entirely surrounding staple cavity openings defined in a cartridge body;</li><li><figref idref="f0018">FIG. 16A</figref> is a partial perspective view of a staple cartridge in accordance with at least one alternative embodiment comprising a plurality of ridges entirely surrounding staple cavity openings defined in a cartridge body;</li><li><figref idref="f0019">FIG. 17</figref> is a perspective view of a staple cartridge in accordance with at least one alternative embodiment comprising a plurality of longitudinal ridges extending from a cartridge body;</li><li><figref idref="f0020">FIG. 18</figref> is a detail view of the staple cartridge of <figref idref="f0019">FIG. 17</figref>;</li><li><figref idref="f0021">FIG. 19</figref> is a perspective view of a surgical instrument that has an interchangeable shaft assembly operably coupled thereto;</li><li><figref idref="f0022">FIG. 20</figref> is an exploded assembly view of the interchangeable shaft assembly and surgical instrument of <figref idref="f0021">FIG. 19</figref>;</li><li><figref idref="f0023">FIG. 21</figref> is an exploded assembly view of a portion of the surgical instrument of <figref idref="f0021">FIGS. 19</figref> and <figref idref="f0022">20</figref>;</li><li><figref idref="f0024">FIG. 22</figref> is another exploded assembly view showing portions of the interchangeable shaft assembly and surgical instrument of <figref idref="f0021 f0022 f0023">FIGS. 19-21</figref>;</li><li><figref idref="f0025">FIG. 23</figref> is a perspective view of a staple cartridge positioned in an end effector of a surgical instrument in accordance with at least one embodiment, wherein the staple cartridge comprises a plurality of ridges extending from a cartridge body of the staple cartridge;</li><li><figref idref="f0026">FIG. 24</figref> is an elevational view of a staple in accordance with at least one embodiment;</li><li><figref idref="f0027">FIG. 25</figref> is an elevational view of the staple of <figref idref="f0026">FIG. 24</figref> positioned within a staple cavity in a staple cartridge;</li><li><figref idref="f0028">FIG. 26</figref> is an elevational view of a staple in accordance with at least one embodiment;</li><li><figref idref="f0028">FIG. 27</figref> is an elevational view of an asymmetrical staple in accordance with at least one embodiment;</li><li><figref idref="f0028">FIG. 28</figref> is an elevational view of another asymmetrical staple in accordance with at least one embodiment;</li><li><figref idref="f0028">FIG. 29</figref> is an elevational view of another asymmetrical staple in accordance with at least one embodiment;</li><li><figref idref="f0029">FIG. 30</figref> is an elevational view of a staple illustrated in a partially deformed condition;</li><li><figref idref="f0029">FIG. 31</figref> is an elevational view of the staple of <figref idref="f0029">FIG. 30</figref> in a fully deformed condition;</li><li><figref idref="f0030">FIG. 32</figref> is a bottom perspective view of an elongate channel;</li><li><figref idref="f0031">FIG. 33</figref> is a cross-sectional perspective view of another elongate channel;</li><li><figref idref="f0032">FIG. 34</figref> is another cross-sectional view of the elongate channel of <figref idref="f0031">FIG. 33</figref> with a cutting head diagrammatically shown therein;</li><li><figref idref="f0032">FIG. 35</figref> is a bottom view of the elongate channel of <figref idref="f0031">FIGS. 33</figref> and <figref idref="f0032">34</figref>;</li><li><figref idref="f0033">FIG. 36</figref> is a bottom view of another elongate channel;</li><li><figref idref="f0033">FIG. 37</figref> is a bottom view of another elongate channel;</li><li><figref idref="f0034">FIG. 38</figref> is a bottom view of another elongate channel;</li><li><figref idref="f0034">FIG. 39</figref> is a bottom view of another elongate channel;</li><li><figref idref="f0035">FIG. 40</figref> is a partial side view of an elongate channel and cutting head with the elongate channel shown in cross-section and portions of the surgical staple cartridge omitted for clarity and with the cutting head in an unlocked position and ready for firing;</li><li><figref idref="f0035">FIG. 41</figref> is another partial side view of the elongate channel and cutting head of <figref idref="f0035">FIG. 40</figref> with the cutting head biased in a locked position;</li><li><figref idref="f0036">FIG. 42</figref> is perspective view of a cutting head and firing bar embodiment;</li><li><figref idref="f0037">FIG. 43</figref> is a perspective view of another end effector and shaft arrangement;</li><li><figref idref="f0037">FIG. 44</figref> is another perspective view of the end effector and shaft arrangement of <figref idref="f0037">FIG. 43</figref> with a portion of the outer shaft omitted for clarity;</li><li><figref idref="f0038">FIG. 45</figref> is a partial side view of another end effector and shaft arrangement;</li><li><figref idref="f0039">FIG. 46</figref> is a partial side elevational view of an end effector arrangement with the elongate channel omitted for clarity;</li><li><figref idref="f0039">FIG. 47</figref> is a top view of an anvil embodiment;</li><li><figref idref="f0039">FIG. 48</figref> is a top view of another anvil embodiment;</li><li><figref idref="f0040">FIG. 49</figref> is a cross-sectional view of an end effector of a surgical instrument in accordance with at least one embodiment comprising a staple cartridge including a stepped cartridge deck;</li><li><figref idref="f0041">FIG. 49A</figref> is the same cross-sectional view depicted in <figref idref="f0040">FIG. 49</figref> illustrating various gap heights between the stepped cartridge deck and an anvil positioned opposite thereto;</li><li><figref idref="f0042">FIG. 50</figref> is an elevational view of an asymmetrical staple in accordance with at least one embodiment;</li><li><figref idref="f0042">FIG. 51</figref> is an elevational view of another asymmetrical staple in accordance with at least one embodiment;</li><li><figref idref="f0042">FIG. 52</figref> is an elevational view of another asymmetrical staple in accordance with at least one embodiment;</li><li><figref idref="f0043">FIG. 53</figref> is a perspective view of a staple sled in accordance with at least one embodiment;</li><li><figref idref="f0043">FIG. 54</figref> is a top view of the staple sled of <figref idref="f0043">FIG. 53</figref>;</li><li><figref idref="f0044">FIG. 54A</figref> is a partial top view of the staple cartridge of <figref idref="f0025">FIG. 23</figref> illustrating the staple sled of <figref idref="f0043">FIG. 53</figref> in a proximal, unfired position;</li><li><figref idref="f0044">FIG. 54B</figref> is a partial, cross-sectional perspective view of the staple cartridge of <figref idref="f0025">FIG. 23</figref>;</li><li><figref idref="f0045">FIG. 54C</figref> is partial rear perspective view of the staple cartridge of <figref idref="f0025">FIG. 23</figref>;</li><li><figref idref="f0045">FIG. 54D</figref> is a perspective view of the staple sled of <figref idref="f0043">FIG. 53</figref>;</li><li><figref idref="f0046">FIG. 55</figref> is a perspective view of a distal end of the staple cartridge of <figref idref="f0025">FIG. 23</figref>;</li><li><figref idref="f0047">FIG. 55A</figref> is a perspective view of a projection extending from the staple cartridge of <figref idref="f0025">FIG. 23</figref>;</li><li><figref idref="f0048">FIG. 56</figref> is a perspective view of a staple cartridge in accordance with at least one embodiment including a pattern of ridges extending from a deck of the staple cartridge;</li><li><figref idref="f0049">FIG. 57</figref> is a detail view of the pattern of ridges and the deck of the staple cartridge of <figref idref="f0048">FIG. 56</figref>;</li><li><figref idref="f0050">FIG. 58</figref> is a partial perspective view of a staple cartridge in accordance with at least one embodiment including a pattern of ridges extending from a deck of the staple cartridge;</li><li><figref idref="f0051">FIG. 59</figref> is a partial perspective view of a staple cartridge in accordance with at least one embodiment including a pattern of projections defined in a deck of the staple cartridge;</li><li><figref idref="f0051">FIG. 60</figref> is a detail view of a projection illustrated in <figref idref="f0051">FIG. 59</figref>;</li><li><figref idref="f0052">FIG. 61</figref> is a partial perspective view of a staple cartridge in accordance with at least one embodiment including a pattern of domes extending from a deck of a staple cartridge;</li><li><figref idref="f0052">FIG. 62</figref> is a detail view of a dome illustrated in <figref idref="f0052">FIG. 61</figref>;</li><li><figref idref="f0053">FIG. 63</figref> is a partial perspective view of projections extending from a deck of a staple cartridge in accordance with at least one embodiment;</li><li><figref idref="f0054">FIG. 64</figref> is an exploded perspective view of a surgical staple cartridge and a cartridge cover;</li><li><figref idref="f0054">FIG. 65</figref> is a cross-sectional view of the staple cartridge and cartridge cover of <figref idref="f0054">FIG. 64</figref> with the cartridge cover installed on the staple cartridge;</li><li><figref idref="f0055">FIG. 66</figref> is a perspective view of an anvil of a surgical stapling instrument in accordance with at least one embodiment including projections extending therefrom;</li><li><figref idref="f0056">FIG. 67</figref> is a detail view of the projections illustrated in <figref idref="f0055">FIG. 66</figref>;</li><li><figref idref="f0057">FIG. 68</figref> is a partial perspective view of an anvil of a surgical stapling instrument in accordance with at least one embodiment including projections extending therefrom;</li><li><figref idref="f0058">FIG. 69</figref> is a cross-sectional view of an anvil of a surgical stapling instrument in accordance with at least one embodiment including a first array of projections having a first height adjacent a first row of staple pockets, a second array of projections having a second height adjacent a second row of staple pockets, and a third array of projections having a third height adjacent a third row of staple pockets;</li><li><figref idref="f0059">FIG. 70</figref> is a perspective view of a staple cartridge in accordance with at least one embodiment including projections extending from a stepped deck surface of the staple cartridge;</li><li><figref idref="f0060">FIG. 71</figref> is a detail view of a distal end of the stepped deck surface and the projections of <figref idref="f0059">FIG. 70</figref>;</li><li><figref idref="f0061">FIG. 72</figref> is a detail view of a proximal end of the stepped deck surface and the projections of <figref idref="f0059">FIG. 70</figref>;</li><li><figref idref="f0062">FIG. 73</figref> is a perspective view of a staple cartridge in accordance with at least one embodiment including projections extending from a stepped deck surface of the staple cartridge;</li><li><figref idref="f0063">FIG. 74</figref> is a partial perspective view of a staple cartridge in accordance with at least one embodiment;</li><li><figref idref="f0064">FIG. 75</figref> is a cross-sectional view of an end effector of a surgical stapling instrument in accordance with at least one embodiment comprising a plurality of deployable tissue engaging members;</li><li><figref idref="f0065">FIG. 76</figref> is a cross-sectional view of an end effector of a surgical stapling instrument in accordance with at least one embodiment comprising a plurality of projections extending from a stepped cartridge deck surface;</li><li><figref idref="f0066">FIG. 77</figref> is a cross-sectional view of a cartridge deck of a staple cartridge and a projection extending from the deck configured to support a staple as the staple is deployed from a staple cavity in accordance with at least one embodiment;</li><li><figref idref="f0066">FIG. 78</figref> is a cross-sectional view of another cartridge deck of a staple cartridge and a projection extending from the deck configured to support a staple as the staple is deployed from a staple cavity in accordance with at least one embodiment;</li><li><figref idref="f0067">FIG. 79</figref> is a partial plan view of a deck of a staple cartridge including projections extending from the deck configured to support a staple removably stored in a staple cavity defined in the staple cartridge in accordance with at least one embodiment;</li><li><figref idref="f0068">FIG. 80</figref> is a partial cross-sectional view of a staple cartridge including a first projection configured to support a first leg of a staple removably positioned within a staple cavity and a second projection configured to support a second leg of the staple in accordance with at least one embodiment;</li><li><figref idref="f0069">FIG. 81</figref> is a perspective view of a distal end of a staple cartridge including a deck, a plurality of staple cavities defined in the deck, and an assortment of projections extending from the deck in accordance with at least one embodiment;</li><li><figref idref="f0070">FIG. 82</figref> is a partial perspective view of a staple cartridge including a deck, a plurality of staple cavities defined in the deck, and a plurality of projections extending from the deck which surround the ends of some of the staple cavities, but not others, in accordance with at least one embodiment;</li><li><figref idref="f0071">FIG. 83</figref> is a partial perspective view of a staple cartridge including a deck, a plurality of staple cavities defined in the deck, and a plurality of projections extending from the deck which surround certain ends of the staple cavities, but not others, in accordance with at least one embodiment;</li><li><figref idref="f0072">FIG. 84</figref> is a partial cross-sectional view of a staple cartridge including a deck and a plurality of staple cavities defined in the deck, an array of staples positioned in the staple cavities extending between a proximal end and a distal end of the staple cartridge wherein the array of staples comprises an assortment of staples, and an array of projections extending from the deck extending between the proximal end and the distal end of the staple cartridge wherein the array of projections comprises an assortment of heights in accordance with at least one embodiment;</li><li><figref idref="f0073">FIG. 85A</figref> is a partial cross-sectional view of a staple cartridge deck and a projection extending from the deck wherein the projection is comprised of a compliant material and is illustrated in an uncompressed state in accordance with at least one embodiment;</li><li><figref idref="f0073">FIG. 85B</figref> is a partial cross-sectional view of the staple cartridge deck and projection of <figref idref="f0073">FIG. 85A</figref> illustrating the projection in a partially-compressed state;</li><li><figref idref="f0073">FIG. 85C</figref> is a partial cross-sectional view of the staple cartridge deck and projection of <figref idref="f0073">FIG. 85A</figref> illustrating the projection in a compressed state;</li><li><figref idref="f0074">FIG. 86A</figref> is partial cross-sectional view of a staple cartridge including a cartridge body comprised of a flexible material in accordance with at least one embodiment illustrated in an unflexed condition;</li><li><figref idref="f0074">FIG. 86B</figref> is a partial cross-sectional view of the staple cartridge of <figref idref="f0074">FIG. 86A</figref> illustrated in a flexed condition;</li><li><figref idref="f0075">FIG. 87</figref> is a perspective view of an anvil including a plurality of projections extending from the anvil in accordance with at least one embodiment;</li><li><figref idref="f0076">FIG. 88</figref> is a detail view of a portion of the anvil of <figref idref="f0075">FIG. 87</figref>;</li><li><figref idref="f0077">FIG. 89</figref> is a partial perspective view of an anvil including a plurality of projections extending from the anvil in accordance with at least one embodiment;</li><li><figref idref="f0078">FIG. 90</figref> is a perspective view of an assembly including a staple driver and movable pocket extenders in accordance with at least one embodiment;</li><li><figref idref="f0078">FIG. 91</figref> is an exploded view of the assembly of <figref idref="f0078">FIG. 90</figref>;</li><li><figref idref="f0079">FIG. 92</figref> is a cross-sectional perspective view of a staple cartridge utilizing the assembly of <figref idref="f0078">FIG. 90</figref> illustrated in an undeployed condition;</li><li><figref idref="f0080">FIG. 93</figref> is a cross-sectional elevational view of the staple cartridge of <figref idref="f0079">FIG. 92</figref> illustrating an assembly of <figref idref="f0078">FIG. 90</figref> in a deployed condition and an assembly of <figref idref="f0078">FIG. 90</figref> in an undeployed condition;</li><li><figref idref="f0081">FIG. 94</figref> is a top view of a surgical staple driver;</li><li><figref idref="f0081">FIG. 95</figref> is a perspective view of the surgical staple driver of <figref idref="f0081">FIG. 94</figref>;</li><li><figref idref="f0082">FIG. 96</figref> is a perspective view of another surgical staple driver;</li><li><figref idref="f0082">FIG. 97</figref> is a top view of a staple driver pocket in a portion of a surgical staple cartridge;</li><li><figref idref="f0083">FIG. 98</figref> is an elevational view of an anvil in accordance with at least one embodiment comprising projections having different heights extending therefrom;</li><li><figref idref="f0084">FIG. 99</figref> is a perspective view of a fastener cartridge in accordance with at least one embodiment;</li><li><figref idref="f0085">FIG. 100</figref> is a plan view of the fastener cartridge of <figref idref="f0084">FIG. 99</figref>;</li><li><figref idref="f0085">FIG. 101</figref> is a partial perspective view of a proximal end of the fastener cartridge of <figref idref="f0084">FIG. 99</figref>; and</li><li><figref idref="f0085">FIG. 102</figref> is a partial plan view of the proximal end of the fastener cartridge of <figref idref="f0084">FIG. 99</figref>.</li></ul>

DETAILED DESCRIPTION

0007The present invention is defined by the features of the independent claim. Preferred embodiments are given in the dependent claims. <figref idref="f0083">Fig. 98</figref> and corresponding paragraphs of the description disclose the invention. Turning to <figref idref="f0001">FIG. 1</figref>, a surgical stapling and severing instrument 10 includes a handle portion 12 that can be manipulated in order to position an implement portion 14 in a surgical site. The implement portion 14 includes an end effector 16 attached to an elongate shaft 18. The implement portion 14 can be sized and configured to be inserted through a cannula of a trocar (not shown) into the surgical site in order to perform an endoscopic or laparoscopic surgical procedure. The end effector 16 comprises an upper jaw, or anvil, 20 and a lower jaw 22, wherein the anvil 20 can be moved between an open position and a closed position when the closure trigger 24 of the handle portion 12 is moved, or depressed, toward a pistol grip 26 of the handle portion 12. The depression of the closure trigger 24 advances an outer closing sleeve 28 ofthe elongate shaft 18 wherein the outer closing sleeve 28 contacts the anvil 20 and pivots the anvil 20 into its closed position.

0008The surgeon may rotate the implement portion 14 about its longitudinal axis by twisting a shaft rotation knob 30. Once the end effector 16 has been inserted into an insufflated body cavity, the closure trigger 24 may be released thereby allowing the anvil 20 to be biased open by a spring (not shown) and positioned relative to the targeted tissue. The closure trigger 24 can be locked in its depressed condition and the handle portion 12 further comprises a lock release actuator 44 which can be depressed to unlock the closure trigger 24. Once the anvil 20 and the lower jaw 22 have been suitably positioned relative to the tissue in the surgical site, the closure trigger 24 can be depressed once again in order to close the anvil 20 and compress the tissue against a staple cartridge 42 attached to the bottom jaw 22.

0009Once the anvil 20 has been closed, a firing trigger 32 can be drawn, or depressed, toward the closure trigger 24 and the pistol grip 26 in order to apply a firing force or motion to a firing member and advance the firing member from an unfired position. The firing member comprises a proximal firing rod 34 which is attached to a distal firing bar 36. For example, the firing rod 34 and/or the firing bar 36 can be supported within a frame 38 in shaft 18 which can extend between the handle portion 12 and the end effector 16. As a result of the firing motion applied to the firing member, the firing bar 36 can be advanced distally within a elongate staple cartridge channel 40 of the lower jaw 22 and a staple cartridge 42 positioned within the cartridge channel 40.

0010Referring to <figref idref="f0001">FIG. 2</figref>, the firing bar 36 comprises an attachment portion 48 that is attached to an E-beam 50 which translates within the end effector 16. The E-beam 50 comprises a vertical portion 52 which passes through a narrow longitudinal anvil slot 58 extending through a tissue-contacting surface 60 in the anvil 20, a narrow vertical slot 62 in the staple cartridge 42, and a narrow longitudinal channel slot 64 in the elongate staple channel 40 when the E-beam 50 is advanced distally. Referring now to <figref idref="f0001">FIGS. 2</figref> and <figref idref="f0002">3</figref>, the anvil slot 58 extends upwardly into the anvil 20 and comprises an end which opens into a laterally-widened longitudinal channel 66 sized and configured to receive an upper pin 54 that extends laterally from the vertical portion 52. Similarly, the channel slot 64 extends downwardly into the channel 40 and comprises an end which opens into a laterally-widened longitudinal channel 68 sized and configured to receive one or more lower feet 70 extending laterally from the vertical portion 52.

0011The E-beam 50 further comprises one or more middle pins 72 which extend laterally from the vertical portion 52 and are configured to slide along a top surface of a bottom tray 74 of the staple cartridge 42. The middle pins 72 are configured to seat the staple cartridge 42, or assure that the staple cartridge 42 remains seated, in the channel 40. A longitudinal firing recess 75 formed in the staple cartridge 42 above the bottom tray 74 is sized to allow the middle pins 72 to translate through the staple cartridge 42. The E-beam 50 further comprises a distal drive surface 76 which is configured to translate through the vertical slot 62 in the staple cartridge 42 and drive a wedge sled 78 distally through the staple cartridge 42. The wedge sled 78 can be integrally-formed within the E-beam 50 or it can reside in the staple cartridge 42 and be contacted by the drive surface 76 as the E-beam 50 is advanced distally. The vertical portion 52 of the E-beam 50 further comprise a cutting surface 80 which extends along a distal edge above the distal drive surface 76 and below the upper pin 54 and that severs the clamped tissue 46 as the tissue 46 is being stapled.

0012Referring now to <figref idref="f0003">FIG. 4</figref>, the wedge sled 78 is configured to engage one or more staple drivers 82 and drive the staple drivers 82 upwardly toward the anvil 20. Staples, such as staples 83, are seated on or otherwise supported by the staple drivers 82 such that, as the staple drivers 82 are lifted upwardly, the staples 83 are lifted as well. For example, the staples 83 can also be at least partially positioned within staple cavities, or pockets, 84 in a staple cartridge body 85 of the staple cartridge 42 wherein, as the staples 83 are lifted upwardly, the staples 83 contact the anvil 20 and are ejected from the staple cavities 84. Referring again to <figref idref="f0003">FIG. 4</figref>, the bottom tray 74 is attached to the cartridge body 85 to retain the staple drivers 82 and the staples 83 within the staple cartridge 42 until the staples 83 are deployed as described above.

0013In use, referring now to <figref idref="f0004">FIGS. 5</figref> and <figref idref="f0005">6</figref>, the anvil 20 is positioned on one side of the tissue 46 and the bottom jaw 22 is positioned on the opposite side of the tissue 46 such that, when the anvil 20 is closed onto the tissue, the tissue-contacting surface 60 of the anvil 20 and the tissue-contacting deck 90 of the staple cartridge 42 compress the tissue 46 between an uncompressed thickness 91 and a compressed thickness 92. In order to staple and transect the tissue 46, as described above, the wedge sled 78 is advanced distally within the staple cartridge 42 to lift the staple drivers 82 toward the anvil 20 and deform the staples 83. Each staple driver 82 comprises one or more slots defined therein which are configured to receive and releasably hold the bases 87 of the staples 83 in position. Each staple 83 comprises one or more staple legs 88 extending from the base 87, wherein the staple legs 88 extend upwardly into the staple cavities 84. The tips of the staple legs 88 are recessed with respect to the deck, or tissue-contacting surface, 90 of the cartridge body 85 when the staples 83 are in their unfired position. As the staples 83 are being lifted upwardly by the drivers 82, the tips of the staple legs 88 emerge from the staple cavities 84, penetrate the tissue 46, and contact the anvil forming pockets 89 positioned opposite the staple cavities 84. The anvil forming pockets 89 are configured to deform the staples 83 into any suitable shape, such as the B-form shape depicted in <figref idref="f0004">FIG. 5</figref>. As the staples 83 are deployed, referring now to <figref idref="f0005">FIG. 6</figref>, the cutting edge 80 transects the tissue 46 into stapled portions 94.

0014As described above, the jaw members of an end effector are configured to apply a compressive pressure, or force, to the tissue being stapled. However, the tissue can be slippery, and at least a portion of the tissue can slide relative to the jaw members. The tissue can slide out of the distal end of the end effector in a longitudinal direction and/or slide out of the sides of the end effector in a direction which is transverse to the longitudinal direction. Portions of the tissue can milk out of the distal end of the end effector and/or the sides of the end effector when the tissue is compressed. The staple cartridge can comprise one or more tissue retention features which are configured to prevent, or at least reduce the possibility of, tissue positioned within the end effector from moving relative to the end effector.

0015Referring now to <figref idref="f0006">FIGS. 7</figref> and <figref idref="f0007">8</figref>, a staple cartridge, such as staple cartridge 142, comprises a cartridge body 185 and a plurality of staples, such as staples 187 (<figref idref="f0009">FIG. 9</figref>), positioned within the cartridge body 185. The cartridge body 185 comprises a proximal end 141 and a distal end 143, wherein the proximal end 141 is configured to be inserted into a proximal end of a staple cartridge channel and the distal end 143 is configured to be inserted into a distal end of the staple cartridge channel. The cartridge body 185 comprises a plurality of staple cavities 184 which are each configured to receive a staple 187 therein. Alternatively, although not illustrated, a staple cavity can comprise more than one staple positioned therein. In any event, the staple cavities 184 are arranged in a plurality of rows within the cartridge body 185. More particularly, the staple cavities 184 illustrated are arranged in three staple rows on a first side 145 of the cartridge body 185 and three staple rows on a second side 147 ofthe cartridge body 185. The first side 145 and the second side 147 of the cartridge body 185 are separated by a knife slot 162 which is configured to slidably receive a cutting member therein. Alternatively, the cartridge can comprise any other suitable number of staple rows, such as two staple rows or four staple rows, on each side of the knife slot 162. Referring to <figref idref="f0009">FIG. 9</figref>, the staple cartridge 142 further comprises a plurality of staple drivers 182 configured to support the staples 187 and/or eject the staples 187 from the staple cavities 184. Each staple cavity 184 comprises an open end, or opening, 110 in the deck 190 of the cartridge body 185 through which the staples 187 can be ejected.

0016Referring primarily to <figref idref="f0007">FIG. 8</figref>, the staple cavities 184 are arranged such that they are staggered longitudinally relative to one another. For example, the staple cavities 184 on the first side 145 of the cartridge body 185, can be arranged in an innermost row of staple cavities 184, an intermediate row of staple cavities 184, and an outermost row of staple cavities 184, wherein the staple cavities 184 in one row may not be aligned transversely with the staple cavities 184 in one or both of the other rows. Each staple cavity 184 comprises a proximal end 111 and a distal end 112, wherein the proximal end 111 of each staple cavity 184 is positioned closer to the proximal end 141 of the cartridge body 185 than the distal end 112. Likewise, the distal end 112 of each cavity 184 is positioned closer to the distal end 143 of the cartridge body 185 than the proximal end 111. The innermost row of staple cavities 184 are positioned such that the distal ends 112 of the staple cavities 184 within the innermost row are positioned distally with respect to the distal ends 112 of the staple cavities 184 in the intermediate row of staple cavities 184. Similarly, the outermost row of staple cavities 184 are positioned such that the distal ends 112 of the staple cavities 184 within the outermost row are positioned distally with respect to the distal ends 112 of the staple cavities in the intermediate row of staple cavities 184. Thus, the distal-most staple cavity 184 in the innermost row is positioned distally with respect to the distal-most staple cavity 184 in the intermediate row and, similarly, the distal-most staple cavity 184 in the outermost row is positioned distally with respect to the distal-most staple cavity 184 in the intermediate row. The staple cavities 184 of the innermost row and the staple cavities 184 of the outermost row can be aligned transversely with each other such that, one, the distal ends 112 of the innermost staple cavities 184 are aligned with the distal ends 112 of the outermost staple cavities 184 and, two, the proximal ends 111 of the innermost staple cavities 184 are aligned with the proximal ends 111 of the outermost staple cavities 184. Each staple cavity 184, and their openings 110, can have the same, or at least approximately the same, configuration and, the staple cavities 184 can be spaced equidistantly, or at least substantially equidistantly, relative to one another within a staple row.

0017Referring again to <figref idref="f0006">FIGS. 7</figref> and <figref idref="f0007">8</figref>, the cartridge body 185 of the staple cartridge 142 further comprises one or more ridges, such as ridges 113, 114, and 115, which are configured to contact and compress the targeted tissue. More particularly, referring now to <figref idref="f0008">FIG. 8A</figref>, the anvil 120 of an end effector can be closed in order to compress the tissue T against the staple cartridge 142 wherein, in such circumstances, the tissue-contacting deck 190 and the ridges 113, 114, and 115 extending therefrom engage the tissue. As the anvil 120 is closed, the anvil 120 pushes the tissue toward the staple cartridge 142 such that the tissue first contacts the ridges 113, 114, and 115 and then contacts the cartridge deck 190. Alternatively, the staple cartridge 142 can be positioned against the tissue such that the ridges 113, 114, and 115 contact the tissue before the tissue is contacted by the cartridge deck 190. In any event, the ridges 113, 114, and 115, once in contact in with the tissue, prevent, or at least limit, relative movement between the tissue and the staple cartridge 142.

0018The ridges 113, 114, and 115 extend upwardly from a flat, or at least substantially flat, cartridge deck 190 and define one or more pockets or channels, which are configured to receive a portion of the tissue therein and, as a result, inhibit the relative movement of the tissue in the longitudinal direction and/or the transverse direction of the end effector, especially when the tissue is at least partially compressed between the anvil 120 and the ridges 113, 114, and 115. As the ridges 113, 114, and 115 extend above the cartridge deck 190, the tissue positioned between the anvil 120 and the ridges 113, 114, and 115 is compressed before the tissue positioned between the anvil 120 and the cartridge deck 190 is compressed. As a result, the tissue positioned between the anvil 120 and the ridges 113, 114, and 115 can be precompressed, i.e., at least partially compressed before the other portions of the tissue positioned between the anvil 120 and the cartridge deck 190 are compressed. Owing to this pre-compression, portions of the tissue can be controlled or prevented from slipping out of the end effector before the tissue is fully compressed as described in greater detail below.

0019Referring again to <figref idref="f0006">FIGS. 7</figref> and <figref idref="f0007">8</figref>, the ridges 113 extending from the cartridge deck 190 extend around the proximal ends 111 of the staple cavity openings 110. Similarly, the ridges 114 extending from the cartridge deck 190 extend around the distal ends 112 of the staple cavity openings 110. These proximal ridges 113 and distal ridges 114, are configured to engage the tissue positioned above and/or around the staple cavities 184 and hold these portions of the tissue in position as the tissue is being compressed and/or stapled. Stated another way, holding the tissue positioned above and/or surrounding the staple cavities 184 can provide localized control over the portions of the tissue that are going to be stapled and, as a result, prevent, or at least limit, the relative movement between these portions of the tissue and the staple cartridge 142. The ridges 113 and 114 can be positioned around the openings 110 of all of the staple cavities 184 or only some of the staple cavities 184. The cartridge body may comprise ridges 113 and 114 surrounding only the staple cavities 184 in the outermost rows of the first and second sides 145 and 147. In such cases, the ridges surrounding the outermost rows of staple cavities 184 may be sufficient to block the lateral movement of the tissue within the end effector. On the other hand, the cartridge body could only comprise proximal ridges 113 surrounding the proximal ends 111 of the proximal-most staple cavities 184 and/or distal ridges 114 surrounding the distal ends 112 of the distal-most staple cavities 184. In such cases, the ridges surrounding the proximal-most and distal-most staple cavities 184 may be sufficient to block the longitudinal movement of the tissue within the end effector.

0020Each proximal ridge 113 comprises an arcuate or curved profile, which surrounds a proximal end 111 of an opening 110. The arcuate profile of each proximal ridge 113 can be defined by one radius of curvature or more than one radius of curvature. Similarly, each distal ridge 114 comprises an arcuate or curved profile, which surrounds a distal end 112 of an opening 110. The arcuate profile of each distal ridge 114 can be defined by one radius of curvature or more than one radius of curvature. Each ridge 113 and 114 forms a pocket which can receive a portion of tissue that is being compressed and prevent that portion of tissue from moving longitudinally and/or transversely relative to the staple cartridge 142. The staple cartridge 142 further comprises intermediate ridges 115 which can extend between and/or connect adjacent ridges 113 and 114 in adjacent rows of staple cavities 184. For example, one or more ridges 113, 114, and 115 cooperatively form an undulating ridge extending across the first side 145 or the second side 147 of the cartridge body 185 wherein, the undulating ridge extends between a center portion and a side portion of the cartridge body 142. Each undulating ridge comprises a plurality of wave portions winding around the proximal and distal ends of the staple cavities 184. Each ridge 113, 114, and 115 comprises a height defined from the cartridge deck 190 wherein the height of each ridge 113, 114, and 115 can be uniform, or at least substantially uniform, across the length thereof. Each ridge 113, 114, and 115 can have the same, or at least substantially the same, height.

0021As described above, the staple cavities defined in a staple cartridge body can comprise a staple positioned therein wherein the entirety of the staple can be positioned below the top surface, or tissue-contacting surface, of the cartridge deck when the staple is in its unfired position. Alternatively, at least a portion of the staple, such as the tips of the staple legs, can extend above the top surface, or tissue-contacting surface, of the cartridge deck when the staples are in their unfired position. In some cases, the tips of the staples protrude from the deck and may snag on tissue as the staple cartridge is inserted into a surgical site. The ridges 113 and 114 of <figref idref="f0009">FIG. 9</figref>, which extend above the tissue-contacting cartridge deck 190, at least partially surround and protect the staple legs 183 of staples 187 when they extend above the cartridge deck 190 in their unfired position. Although the ridges 113 and 114 may not extend entirely around each opening 110, the proximal ridge 113 sufficiently surrounds one of the staple leg tips and the distal ridge 114 sufficiently surrounds the other staple leg tip such that the staple leg tips do not contact the tissue prior to the tissue being compressed against the staple cartridge 142 and/or the staples 187 being ejected from the staple cartridge 142. The staple leg tips can be positioned below the top surfaces 116 of the ridges 113 and 114. The staple leg tips can lie in a common plane with the top surfaces 116 of the ridges 113 and 114. As a result of the protection afforded by the ridges 113 and 114, staples having a taller staple height can be used without the staple tips protruding from the staple cartridge 142 in their unfired position. Referring again to <figref idref="f0009">FIG. 9</figref>, the ridges 113 and 114 depicted extend or increase the length in which the staple legs 183 of the staples 187 can be controlled and/or supported. For example, each ridge 113 and 114 extends or increases the length in which the staple legs 183 are supported on three sides thereof. This can prevent, or at least reduce the possibility of, the staple legs 183 buckling when they are inserted through dense tissue, such as bronchus tissue.

0022Referring again to <figref idref="f0003">FIG. 4</figref>, the cartridge body 85 depicted comprises cavities 84, slot 62, and channels 86, defined therein which reduce the strength of the cartridge body 85. Especially when the cartridge body 85 is compressed by the anvil 20, the cartridge body 85 can deflect as a result of the load applied thereto. For example, the portions of the cartridge deck 90 extending over the channels 86, may be especially thin and may be especially subject to deflection and/or breakage. Referring again to <figref idref="f0006">FIGS. 7</figref> and <figref idref="f0007">8</figref>, the ridges 113, 114, and/or 115 depicted are configured to strengthen and/or stiffen the cartridge body 185. For example, the ridges 113 and 114, extend around the openings 110 to strengthen and/or stiffen the portions of the cartridge body 185 surrounding the staple cavities 184. The ridges 115, extend transversely over channels 86 defined within the cartridge body 185 such that the ridges 115 strengthen and/or stiffen the cartridge body 185 surrounding the channels 86. Alternatively, the cartridge body 185 can comprise any suitable number and configuration of ridges extending therefrom in order to achieve the advantages described herein.

0023The staple cartridge body 185 can consist of plastic materials, metallic materials, and/or ceramic materials. The materials can comprise liquid crystal polymers, such as Vectra, thermoplastic polymers, such as polycarbonate, ABS, Noryl, polyamides (nylons), polyethersulfones, polyetherimides, such as Ultem, and/or polymer blends of two or more of the aforementioned thermoplastic polymers, wherein, the cartridge body 185 can be formed by an injection molding process. The materials can comprise thermoset polymers, like thermoset polyesters, investment cast stainless steels, such as 17-4 PH, and/or metal Injection molded stainless steels, such as 17-4 PH. For example, the ridges 113, 114, and/or 115 can be integrally formed with the cartridge deck 190 of the cartridge body 185. Or the ridges 113, 114, and/or 115 can be attached to the cartridge deck 190 by at least one adhesive.

0024Referring now to <figref idref="f0012">FIG. 12</figref>, the staple cartridge 342 depicted, comprises a cartridge body 385, a plurality of staple cavities 384 defined in the cartridge body 385, and a staple positioned in each of the staple cavities 384. The cartridge body 385 further comprises a first side 345 comprising a first group of staple cavities 384, a second side 347 comprising a second group of staple cavities 384, and a cartridge deck 390. The cartridge body 385 further comprises a plurality of ridges 315 extending from the cartridge deck 390 which are positioned between adjacent staple cavities 384 in a row of staple cavities 384. Each ridge 315 comprises a cross-shaped or X-shaped configuration. For example, each ridge 315 comprises a V-shaped portion 313 which at least partially surrounds a proximal end 311 of a staple cavity opening 310 and, in addition, a V-shaped portion 314 which at least partially surrounds a distal end 312 of another staple cavity opening 310. Only the outermost rows of staple cavities 384 in cartridge body 385 are at least partially surrounded by ridges 315. Alternatively, referring now to <figref idref="f0013">FIG. 13</figref>, a staple cartridge body 385' can comprise ridges 315 which at least partially surround the opening 310 of every staple cavity 384 in the cartridge body. In any event, each ridge 315 is configured to compress and control tissue positioned against the staple cartridge 342 as described above and/or surround the staple legs of the staples extending above the deck 390.

0025Referring now to <figref idref="f0017">FIG. 16</figref>, the staple cartridge 542 depicted, comprises a cartridge body 585, a plurality of staple cavities 584 defined in the cartridge body 585, and a staple positioned in each of the staple cavities 584. The cartridge body 585 further comprises a first side 545 comprising a first group of staple cavities 584, a second side 547 comprising a second group of staple cavities 584, and a cartridge deck 590. The cartridge body 585 further comprises a plurality of ridges 515 extending from the cartridge deck 590, wherein each ridge 515 entirely surrounds or encompasses a staple cavity opening 510. As illustrated in <figref idref="f0017">FIG. 16</figref>, some cavity openings 510 in the cartridge body 585 may not be surrounded by a ridge 515; whereas, alternatively, referring now to <figref idref="f0018">FIG. 16A</figref>, every cavity opening 510 in a cartridge body 585' could be surrounded by a ridge 515. It is contemplated that the cartridge body may comprise a first group of staple cavities 584 which are surrounded by a ridge 515 and a second group of staple cavities 584 which are not surrounded by a ridge 515, wherein staples having a taller staple height can be positioned in the first group of staple cavities 584 and wherein staples having a shorter staple height can be positioned in the second group of staple cavities 584 such that neither the taller staples nor the shorter staples protrude from the staple cartridge 542. For example, the cartridge body are configured to utilize taller staples in one row of staple cavities 584 and shorter staples in another row of staple cavities 584. In an exemplary arrangement, ridges 515 surround all of the staple cavities 584 in the outermost rows of staple cavities 584 in the cartridge body such that taller staples can be utilized in the outermost rows and shorter staples can be utilized in the innermost rows and/or intermediate rows of staple cavities 584.

0026Referring now to <figref idref="f0014">FIG. 14</figref>, the staple cartridge 442 depicted, comprises a cartridge body 485, a plurality of staple cavities 484 defined in the cartridge body 485, and a staple positioned in each of the staple cavities 484. The cartridge body 485 further comprises a first side 445 comprising a first group of staple cavities 484, a second side 447 comprising a second group of staple cavities 484, and a cartridge deck 490. The cartridge body 445 further comprises a plurality of ridges 415 extending from the cartridge deck 490, wherein each ridge 415 comprises a plurality, or array, of knurls. An anvil is utilized to position tissue against the knurls such that the tissue conforms to the contour of the knurls. Each ridge 415 comprises a plurality of pyramidal-shaped, or diamond-shaped, knurls, at least partially surrounding one or more staple cavity openings 410 wherein, the pyramidal-shaped knurls point upwardly from the cartridge deck 490. Each pyramidal knurl comprises four triangular sides which converge together to form a sharp point. Referring to <figref idref="f0016">FIG. 15A</figref>, the pyramidal knurls of ridges 415 are truncated, wherein the top of each knurl comprise a flat top surface surrounded by inclined sides. Although foursided pyramidal knurls can be utilized, referring now to <figref idref="f0016">FIG. 15C</figref>, other pyramidal shapes are contemplated which have fewer than four sides or more than four sides, such as three sides. One or more ridges 415 may comprise a plurality of cone-shaped knurls, wherein each cone-shaped knurl comprises a circular, or at least substantially circular, base which tapers upwardly to form a sharp point. Referring now to <figref idref="f0016">FIG. 15B</figref>, the cone-shaped knurls can be truncated, wherein the top of each knurl comprises a flat top surface surrounded by an annular side. Referring again to <figref idref="f0014">FIG. 14</figref>, the knurls of the ridges 415 depicted, extend along the lateral sides of the staple cavity openings 410 and/or between adjacent staple cavity openings 410. The knurls extend around the proximal ends 411 and/or the distal ends 412 of the staple cavity openings 410. The knurls of ridges 415 may only surround some of the staple cavities 484 while, alternatively, referring to <figref idref="f0015">FIG. 15</figref>, the knurls of ridges 415 may cover the entirety, or at least the substantial entirety, of the cartridge deck 490.

0027Referring now to <figref idref="f0010">FIG. 10</figref>, the staple cartridge 242 depicted, comprises a cartridge body 285, a plurality of staple cavities 284 defined in the cartridge body 285, and a staple positioned in each of the staple cavities 284. The cartridge body 285 further comprises a first side 245 comprising a first group of staple cavities 284, a second side 247 comprising a second group of staple cavities 284, and a cartridge deck 290. The cartridge body 285 further comprises a plurality of ridges, or bumps, 215 extending from the cartridge deck 290. For example, each ridge 215 can extend transversely between a center, or middle, portion of the cartridge body 245 positioned adjacent to a knife slot 262 and a lateral portion of the cartridge body 245. More particularly, referring specifically to the first side 245 of the cartridge body 285 depicted, each ridge 215 comprises a first end 213 positioned adjacent to the knife slot 262 and a second end 214 positioned adjacent to the first side 261 of the cartridge body 285. Similarly, referring now to the second side 247 of the cartridge body 285, each ridge 215 comprises a first end 213 positioned adjacent to the knife slot 262 and a second end 214 positioned adjacent to the second side 263 of the cartridge body 285. Each ridge 215 comprises a height measured from the deck 290 wherein, in at least one such embodiment, the height of each ridge 215 can vary along the length thereof. The second end 214 is taller than the first end 213 and the height of each ridge 215 tapers between the second end 214 and the first end 213. Alternatively, although not illustrated, the first end 213 of the ridge 215 can be taller than the second end 214. The height of each ridge 215 tapers linearly, or at least substantially linearly, between the ends 213 and 214. For example, the height of each ridge 215 can taper between a maximum height at the second end 214 down to no height at all at the first end 213. The height of each ridge 215 can vary geometrically between the ends 213 and 214. Alternatively, referring now to <figref idref="f0011">FIG. 11</figref>, each ridge 215' can comprise a uniform height across the length thereof.

0028As described above, the inner ends 213 of the ridges 215 can be shorter than the outer ends 214 of the ridges 215. as a result, the inner ends 213 apply less pressure to the tissue clamped between an anvil and the staple cartridge 242 as compared with the outer ends 214. Each ridge 215 extends transversely along a ridge axis which transects a longitudinal axis 299 of the cartridge body 285. For example, the ridge axes can be perpendicular, or at least substantially perpendicular, to the longitudinal axis 299. The staple cavities 284 are arranged in a plurality of rows, wherein each row of staple cavities 284 is defined along a longitudinal axis which is parallel to, or at least substantially parallel to, the longitudinal axis 299. The ridge axes of the ridges 215 extends in a direction which transect the longitudinal axes of the staple cavities 284. For example, the ridge axes of the ridges 215 can extend in a direction which is perpendicular, or at least substantially perpendicular, to the longitudinal axes of the staple cavities 284. Referring again to <figref idref="f0010">FIG. 10</figref>, each ridge 215 comprises a crest 209 and, in addition, sloped surfaces 208 extending between the crest 209 and the cartridge deck 290. Each sloped surface 208 comprises one or more flat surfaces, curved surfaces, concave surfaces, and/or convex surfaces. Each ridge 215 extend along a path which extends across one or more openings 210 of the staple cavities 284. For example, such openings 210 can extend upwardly through the ridges 215. As the ridges 215 extend transversely across the cartridge deck 290, the ridges 215, similar to the ridges 115, increase the strength and/or stiffness of the cartridge body 285.

0029Referring now to <figref idref="f0019">FIGS. 17</figref> and <figref idref="f0020">18</figref>, the staple cartridge 642 depicted, comprises a cartridge body 685, a plurality of staple cavities 684 defined in the cartridge body 685, and a staple positioned in each of the staple cavities 684. The cartridge body 685 further comprises a first side 645 comprising a first group of staple cavities 684, a second side 647 comprising a second group of staple cavities 684, and a cartridge deck 690. The cartridge body 685 further comprises a plurality of ridges, or bumps, 615 extending from the cartridge deck 690. For example, each ridge 615 can extend in a longitudinal direction, wherein each ridge 615 comprises a distal end 613 and a proximal end 614, wherein the distal end 613 of the ridge 615 is closer to the distal end 643 of the cartridge body 685, and wherein the proximal end 614 of the ridge 615 is positioned closer to the proximal end 641. Each ridge 615 comprises a height measured from the deck 690 wherein the height of each ridge 615 varies along the length thereof. The proximal end 614 is taller than the distal end 613 and the height of each ridge 615 tapers between the proximal end 614 and the distal end 613. Alternatively, although not illustrated, the distal end 613 of the ridge 615 can be taller than the proximal end 614. The height of each ridge 615 tapers linearly, or at least substantially linearly, between the ends 613 and 614. For example, the height of each ridge 615 tapers between a maximum height at the proximal end 614 down to no height at all at the distal end 613. The height of each ridge 615 varies geometrically between the ends 613 and 614. Alternatively, each ridge 615 can comprise a uniform height across the length thereof.

0030As described above, the distal ends 613 of the ridges 615 can be shorter than the proximal ends 614 ofthe ridges 615. As a result, the distal ends 613 apply less pressure to the tissue clamped between an anvil and the staple cartridge 642 as compared with the proximal ends 614. As described above, each ridge 615 extends longitudinally across the cartridge deck 690. Each ridge 615 extends along a ridge axis which is parallel to, or at least substantially parallel to, a longitudinal axis 699 of the cartridge body 685. The staple cavities 684 are arranged in a plurality of rows, wherein each row of staple cavities 684 is defined along a longitudinal axis which is parallel to, or at least substantially parallel to, the ridge axes of ridges 615. Referring again to <figref idref="f0020">FIG. 18</figref>, each ridge 615 comprises a ramped surface which comprises one or more flat surfaces, curved surfaces, concave surfaces, and/or convex surfaces. For example, the bottom of the ramped surface can face distally which can facilitate the sliding of tissue across the staple cartridge 642 when the tissue is positioned in the end effector. Each ridge 615 extends along a path which extends across one or more openings 610 of the staple cavities 684. For example, such openings 610 may extend upwardly through the ridges 615. As the ridges 615 extend transversely across the cartridge deck 690, the ridges 615 increase the strength and/or stiffness of the cartridge body 685.

0031The surgical staples can consist of titanium, such as titanium wire, or an alloy comprising titanium, aluminum, and/or vanadium. Each staple can consist of surgical stainless steel and/or an alloy comprised of cobalt and chromium. In any event, the surgical staple can consist of metal, such as titanium, and a metal oxide outer surface, such as titanium oxide. The metal oxide outer surface can be coated with a material. The coating material can consist of polytetrafluoroethylene (PTFE), such as Teflon®, and/or a tetrafluoroehtylene (TFE) such as ethylene-tetrafluoroehtylene (ETFE), perfluroralkoxyethylene-tetrafluoroehtylene (PFA), and/or Fluorinated Ethylene Propylene (FEP). Certain coatings can comprise silicon. Such coating materials can prevent, or at least inhibit, further oxidation of the metal. The coating materials can provide one or more lubricious surfaces against which the anvil, or staple pockets, can contact the staples in order to reduce the friction force therebetween. lower friction forces between the staples and the staple pockets can reduce the force required to deform the staples.

0032An end effector of a surgical stapling instrument is illustrated in <figref idref="f0025">FIGS. 23</figref> and <figref idref="f0046">55</figref>. The end effector includes an anvil, such as anvil 20, and a jaw, or staple cartridge channel, 22 configured to removably support a staple cartridge therein. A staple cartridge 2000, is positioned in the cartridge channel 22. The staple cartridge 2000 comprises a cartridge body 2010 including a plurality of staple cavities 2050 defined therein. Each staple cavity 2050 is configured to removably store a staple therein. The cartridge body 2010 includes a deck surface 2011 and a longitudinal slot 2015 defined in the deck surface 2011 configured to removably receive a firing member and/or cutting edge therein. The cartridge body 2010 further comprises a distal end 2013, a proximal end 2016, and opposing longitudinal sides 2012 extending between the distal end 2013 and the proximal end 2016. Each longitudinal side 2012 can comprise a contiguous or continuous edge without interruptions defined therein. Upon comparing <figref idref="f0006">FIGS. 7</figref> and <figref idref="f0025">23</figref>, for instance, the reader will appreciate that the longitudinal sides of the staple cartridge 142 depicted in <figref idref="f0006">FIG. 7</figref> comprises at least one notch defined therein while the longitudinal sides 2012 comprise no such notches.

0033Referring primarily to <figref idref="f0046">FIG. 55</figref>, the cartridge body 2010 further comprises a plurality of projections 2051 extending from the deck surface 2011. Projections 2051 are configured to engage tissue positioned between the anvil 20 and the cartridge 2000 and control the movement of the tissue relative to the cartridge 2000. Tissue can move relative to the cartridge 2000, e.g. tissue can flow relative to the cartridge 2000 when the anvil 20 is moved between an open position (<figref idref="f0025">FIG. 23</figref>) and a closed position in which the tissue is squeezed between the anvil 20 and the cartridge 2000. The tissue may flow laterally toward the longitudinal sides 2012, distally toward the distal end 2013, and/or proximally toward the proximal end 2016. Tissue can also flow relative to the cartridge 2000 when the cutting edge is advanced distally through the tissue captured between the anvil 20 and the cartridge 2000. In such cases, tissue may flow laterally, distally, and/or proximally, but it primarily flows distally due to the distal movement of the cutting edge. As illustrated, projections 2051 are configured to limit or prevent the flow of the tissue relative to the staple cartridge. Projections 2051 are positioned at the proximal end and/or the distal end of the staple cavities 2050. Each projection 2051 comprises a cuff extending around an end of a staple cavity 2050. Each projection 2051 may comprise an arcuate ridge extending around an end of a staple cavity 2050.

0034Referring primarily to <figref idref="f0046">FIG. 55</figref>, the cartridge body 2010 comprises a sloped transition 2014 extending between the distal tip of the cartridge body 2010 and the deck surface 2011. The sloped transition 2014 facilitates the movement of the cartridge 2000 relative to the tissue when positioning the cartridge 2000 and the anvil 20 within a surgical site; the tissue can slide over the sloped surface 2014. The sloped surface 2014 can comprise a radiused surface, an angled surface, a concave surface and/or a convex surface. For example, as illustrated in <figref idref="f0046">FIG. 55</figref>, the sloped surface 2014 can comprise a distal concave surface which transitions into a flat, angled surface which transitions into a proximal convex surface.

0035The staple cavities 2050 defined in the cartridge body 2010 are arranged in longitudinal rows. For instance, three longitudinal rows of staple cavities 2050 are arranged on a first side of the longitudinal slot 2015 and three longitudinal rows of staple cavities 2050 are arranged on a second side of the longitudinal slot 2105. Each longitudinal row includes a distal-most staple cavity 2050 adjacent to the distal end 2013 and a proximal-most staple cavity 2050 adjacent to the proximal end 2016. The cartridge body 2010 further comprises projections 2053 extending from the deck surface 2011. The projections 2053 can be positioned at the distal ends of the distal-most staple cavities 2050. Each projection 2053 comprises a distal sloped surface, configured to facilitate the insertion of the tissue between the staple cartridge 2000 and the anvil 20. The distal-most cavities 2050 each include a projection 2053 positioned at the distal end thereof and a projection 2051 positioned at a proximal end thereof.

0036Each projection 2051 and/or projection 2053 is configured to support at least a portion of a staple removably stored in a staple cavity 2050. Each projection 2051 extends an endwall 2052 of the staple cavity 2050 above the deck 2011. Referring generally to <figref idref="f0026">FIGS. 24</figref> and <figref idref="f0028">26-29</figref>, a staple positioned within the staple cavity 2050 includes a base, a first leg extending from the base at a first angle, and a second leg extending from the base at a second angle. The first leg is in contact with a first endwall 2052 (<figref idref="f0046">FIG. 55</figref>) of a staple cavity 2050 and the second leg is in contact with a second endwall 2052 of the staple cavity. The distance, or spread, between the first leg and the second leg of the staple can be wider than the distance between the endwalls 2052 such that, when the staple is positioned within the staple cavity 2050, the legs are biased inwardly by the endwalls 2052. When the staple is stored within the staple cavity 2050 in its unfired, or unlifted, position, the tips of the staple legs are positioned within the projections 2051. The projections 2051 support and protect the tips of the staple legs above the deck 2011. In some instances, the tips of the staple legs may be positioned below the projections 2051 when the staple is in its unfired position and, thus, the projections 2051 may not support the staple legs when the staple is in its unfired position. When such a staple is fired, or lifted out of the staple cavity 2050, the staple legs then come into contact with and are supported by the projections 2051. In any event, the projections 2051 continue to support the staple legs as the staple is deployed until the staple has been sufficiently fired and/or lifted out of the staple cavity 2050 such that the staple legs are no longer in contact with the projections 2051. Projections 2053 perform in a similar manner as that described in connection with projections 2051.

0037A projection 2051 can extend a staple cavity 2050 above the deck 2011 of the cartridge body 2010. The projection 2051 may be configured such that an endwall 2052 of the staple cavity 2050 extends seamlessly into the projection 2051. A seamless surface can be defined between the endwall 2052 and the projection 2051. Such a seamless surface reduces the possibility of a staple leg which is biased against the endwall 2052 and the projection 2051 from contacting an edge or step defined within the staple cavity 2050 and/or digging into the sidewall of the staple cavity 2050. <figref idref="f0047">FIG. 55A</figref> illustrates a step 2056 defined between the projection 2051 and the endwall 2052. While the step 2056 comprises an outward step and not an inward step, the step 2056 can be eliminated to provide a seamless surface as discussed above. Where the cartridge body 2010 is formed by an injection molding process, the cartridge 2010 can be formed in a mold cavity defined between two halves of an injection mold. The two halves of the injection mold contact one another to seal, or at least substantially seal, the mold cavity. The interface between the two mold halves is often referred to as the seal line, or parting line, and, oftentimes, a small ledge or lip is formed in the cartridge body along the seal line. This is especially true when the seal line is used to vent air from the mold cavity during the injection molding process. This ledge or lip is often referred to as 'flash'. The injection mold can be carefully designed such that the seal line does not produce a ledge or lip in the endwall 2052 and/or the inwardly-facing surface of the projection 2051.

0038As illustrated, the projection 2051 comprises an end cuff portion 2057 and a transition portion 2058 extending from opposite ends of the cuff portion to the deck 2011. The seal line between the two mold halves is selected such that it extends along the top surface of the projection 2051. An exemplary seal line 2059 is depicted in <figref idref="f0047">FIG. 55A</figref>, although other suitable seal lines could be selected.

0039A staple cartridge 2800 is illustrated in <figref idref="f0048">FIGS. 56</figref> and <figref idref="f0049">57</figref>. The staple cartridge 2800 includes a cartridge body 2810. The cartridge body 2810 comprises a distal end 2813, a proximal end 2816, and opposing lateral sides 2812. Each lateral side 2812 comprises a contiguous edge without notches defined therein. The cartridge body 2810 further includes a deck 2811, a plurality of staple cavities 2850 defined in the deck 2811, and a longitudinal slot 2815 configured to receive a knife edge of a firing member. The cartridge body 2810 further comprises ridges 2851 extending from the deck 2811. The ridges 2851 comprise a pattern. For example, each ridge 2851 extends between a lateral side 2812 and the longitudinal slot 2815. Each ridge 2851 comprises any suitable configuration, such as a plateau. As illustrated, one or more staple cavities 2850 extend through the ridge 2851. For example, at least a portion of a staple cavity 2850 in the inner row of staple cavities 2850, at least a portion of a staple cavity 2850 in the middle row of staple cavities 2850, and/or at least a portion of a staple cavity 2850 in an outer row of staple cavities 2850 extend through the plateau of a ridge 2851. Each ridge 2851 comprises an inner end 2858 positioned adjacent to the longitudinal slot 2815 and an outer end 2859 positioned adjacent to a lateral side 2812. The inner end 2858 is positioned distally with respect to the outer end 2859. Alternatively, the outer end 2859 can be positioned distally with respect to the inner end 2858. The ridges 2851 can be parallel. The ridges 2851 can comprise a tread pattern. The ridges 2851 extending from the deck 2811 on a first side of the longitudinal slot 2815 can comprise a mirror image of the ridges 2851 extending from the deck on a second side of the longitudinal slot 2815. Gaps can be defined between the ridges 2851 so that tissue can flow into the gaps when the tissue is compressed against the cartridge deck 2811 by an anvil. The gaps are configured to direct the flow of tissue in a desired direction.

0040A staple cartridge 2900 is illustrated in <figref idref="f0050">FIG. 58</figref>. The staple cartridge 2900 includes a cartridge body 2910. The cartridge body 2910 comprises a distal end 2913, a proximal end, and opposing lateral sides 2912. Each lateral side 2912 comprises a contiguous edge without notches defined therein. The cartridge body 2910 further includes a deck 2911, a plurality of staple cavities 2950 defined in the deck 2911, and a longitudinal slot 2915 configured to receive a knife edge of a firing member. The cartridge body 2910 further comprises ridges 2951 extending from the deck 2911. Each ridge 2951 extends between the distal end 2913 and the proximal end of the cartridge body 2910. Each ridge 2951 also extends toward a lateral side 2912 and toward the longitudinal slot 2915. Each ridge 2951 comprises angled portions 2954 which extend inwardly and proximally, straight portions 2955 which extend longitudinally, and angled portions 2956 which extend inwardly and distally. The ridges 2951 extend around and/or between the staple cavities 2950. The angled portions 2954 and the angled portions 2956 extend between staple cavities 2950 in a longitudinal row of staple cavities 2950. The ridges 2951 can be parallel to one another. The ridges 2951 can comprise a tread pattern. As shown, the ridges 2951 extending from the deck 2911 on a first side of the longitudinal slot 2915 comprise a mirror image of the ridges 2951 extending from the deck on a second side of the longitudinal slot 2915. Gaps are defined between the ridges 2951. Tissue can flow into the gaps when the tissue is compressed against the cartridge deck 2911 by an anvil. The gaps are configured to direct the flow of tissue in a desired direction.

0041A staple cartridge 3000 is illustrated in <figref idref="f0051">FIGS. 59 and 60</figref>. The staple cartridge 3000 includes a cartridge body 3010. The cartridge body 3010 comprises a distal end 3013, a proximal end, and opposing lateral sides 3012. Each lateral side 3012 may comprise a contiguous edge without notches defined therein. The cartridge body 3010 further includes a deck 3011, a plurality of staple cavities 3050 defined in the deck 3011, and a longitudinal slot 3015 configured to receive a knife edge of a firing member. The cartridge body 3010 further comprise projections 3051 extending from the deck 3011. The projections 3051 comprise a pattern. Each projection 3051 comprises a pyramidal configuration. A pyramidal configuration can include four sides which culminate in a point. Alternatively, the four sides could culminate in a flat surface. Alternatively, a pyramidal configuration can include three sides which culminate in a point. In any event, as illustrated in <figref idref="f0051">FIG. 59</figref>, an array of projections 3051 extends across the deck 3011 between the longitudinal slot 3015 and the lateral sides 3012. The projections 3051 are arranged around the staple cavities 3050. The staple cavities 3050 are arranged in longitudinal rows and the projections 3051 can be positioned between the staple cavities 3050 within a longitudinal row of staple cavities 3050. The projections 3051 can be positioned between staple cavities 3050 in adjacent longitudinal rows of staple cavities 3050. The projections 3051 can be positioned between the innermost rows of staple cavities 3050 and the longitudinal channel 3015. The projections 3051 are also positioned between the outermost rows of staple cavities 3050 and the lateral edges 3012. The projections 3051 can be positioned distally with respect to the distal-most staple cavities 3050. The projections 3051 can be positioned proximally with respect to the proximal-most staple cavities 3050. The projections 3051 may be positioned distally with respect to the distal end of the longitudinal slot 3015. Alternatively, the projections 3051 are not positioned distally with respect to the distal end of the longitudinal slot 3015.

0042A staple cartridge 3100 is illustrated in <figref idref="f0052">FIGS. 61 and 62</figref>. The staple cartridge 3100 includes a cartridge body 3110. The cartridge body 3110 comprises a distal end 3113, a proximal end, and opposing lateral sides 3112. Each lateral side 3112 may comprise a contiguous edge without notches defined therein. The cartridge body 3110 further includes a deck 3111, a plurality of staple cavities 3150 defined in the deck 3111, and a longitudinal slot 3115 configured to receive a knife edge of a firing member. The cartridge body 3110 further comprises projections 3151 extending from the deck 3111. The projections 3151 comprise a pattern. Each projection 3151 comprises a dome configuration. A dome configuration can include a hemi-spherical protrusion. In some instances, a dome could culminate in a flat surface. As illustrated in <figref idref="f0052">FIG. 61</figref>, an array of projections 3151 extends across the deck 3111 between the longitudinal slot 3115 and the lateral sides 3112. The projections 3151 are arranged around the staple cavities 3150. The staple cavities 3150 are arranged in longitudinal rows and the projections 3151 can be positioned between the staple cavities 3150 within a longitudinal row of staple cavities 3150. The projections 3151 can be positioned between staple cavities 3150 in adj acent longitudinal rows of staple cavities 3150. The projections 3151 can be positioned between the innermost rows of staple cavities 3150 and the longitudinal channel 3115. The projections 3151 can be positioned between the outermost rows of staple cavities 3150 and the lateral edges 3112. The projections 3151 can be positioned distally with respect to the distal-most staple cavities 3150. The projections 3151 can be positioned proximally with respect to the proximal-most staple cavities 3150. The projections 3151 may be positioned distally with respect to the distal end of the longitudinal slot 3115. Alternatively, the projections 3151 may not be positioned distally with respect to the distal end of the longitudinal slot 3115.

0043A staple cartridge 3200 is illustrated in <figref idref="f0053">FIG. 63</figref>. The staple cartridge 3200 includes a cartridge body 3210. The cartridge body 3210 comprises a distal end 3213, a proximal end, and opposing lateral sides 3212. Each lateral side 3212 may comprise a contiguous edge without notches defined therein. The cartridge body 3210 further includes a deck 3211, a plurality of staple cavities 3250 defined in the deck 3211, and a longitudinal slot 3215 configured to receive a knife edge of a firing member. The cartridge body 3210 further comprises projections 3251 extending from the deck 3211. Similar to projections 2051, projections 3251 are configured to engage tissue positioned between an anvil and the cartridge 3200 and control the movement of the tissue relative to the cartridge 3200. The projections 3251 are configured to limit or prevent the flow of the tissue relative to the staple cartridge. Projections 3251 can be positioned at the proximal end and/or the distal end of the staple cavities 3250. Each projection 3251 comprises a cuff extending around an end of a staple cavity 3250. Each projection 3251 comprises an arcuate ridge extending around an end of a staple cavity 3250. Each projection 3251 includes one or more protrusions 3254 defined thereon. The protrusions 3254 provide a textured surface which improves the grip or hold that the projections 3251 can apply to the tissue positioned between the anvil and the staple cartridge 3200. Each protrusion 3254 can comprise a nub or a dome. The protrusions 3254 can consist of an elastomeric material, such as rubber, a thermoplastic elastomer, and/or Santoprene, molded onto the projections 3251 which can consist of plastic material. The protrusions 3254 can consist of a pliable material so as not to traumatize the tissue compressed by the protrusions 3254. The cartridge body 3210 further comprises projections 3253. Similar to projections 2053, the projections 3253 can be positioned at the distal ends of the distal-most staple cavities 3250. Each projection 3253 comprises a distal sloped surface, configured to facilitate the insertion of the tissue between the staple cartridge 3200 and the anvil. The distal-most cavities 3250 can each include a projection 3253 positioned at the distal end thereof and a projection 3251 positioned at a proximal end thereof. Moreover, each projection 3251 and/or projection 3253 is configured to support at least a portion of a staple removably stored in a staple cavity 3250.

0044A staple 2130 is illustrated in <figref idref="f0026">FIG. 24</figref> which comprises a base 2131, a first staple leg 2132a extending from a first end of the base 2131, and a second staple leg 2132b extending from a second end of the base 2131. The distance between the first end of the base 2131 and the second end of the base 2131 is referred to as the crown distance, and is indicated by dimension E. The first staple leg 2132a comprises a first portion 2133a extending from the base 2131 and a second portion 2134a extending from the first portion 2133a. The first portion 2133a extends at a first angle from the base 2131. This first angle is indicated by an angle F, which is measured from the vertical direction. The second portion 2134a extends at a second angle from the first portion 2133a. This second angle is indicated by an angle K, which is also measured from the vertical direction. The reader will appreciate that the first portion 2133a and the second portion 2134a are not collinear; rather, the first portion 2133a extends along a first axis 2137a and the second portion 2134a extends along a second axis 2138a which is different from the first axis 2137a. A joint 2135a interconnects the first portion 2133a and the second portion 2134a and is located a distance D measured from a support surface 2139 defined on the bottom of the base 2131. The second portion 2134a includes a leg tip 2136a which is located a distance C measured from the base support surface 2139. The first portion 2133a comprises a first cantilever extending from the base 2131 and the second portion 2134a comprises a second cantilever extending from the first portion 2133a. Distance D defines the first cantilever distance and the difference between distance C and distance D defines the second cantilever distance.

0045The second staple leg 2132b comprises a first portion 2133b extending from the base 2131 and a second portion 2134b extending from the first portion 2133b. The first portion 2133b extends at a first angle from the base 2131. This first angle is indicated by an angle G, which is measured from the vertical direction. Angle G may or may not be the same as angle F, described above. When the second staple leg 2132b is positioned distally with respect to the first staple leg 2132a, angle G can be smaller than angle F. Alternatively, when the first staple leg 2132a is positioned distally with respect to the second staple leg 2132b, angle F can be smaller than angle G. The second portion 2134b extends at a second angle from the first portion 2133b. This second angle is indicated by an angle H, which is also measured from the vertical direction. Angle H may or may not be the same as angle K. When the second staple leg 2132b is positioned distally with respect to the first staple leg 2132a, angle H can be smaller than angle K. Alternatively, when the first staple leg 2132a is positioned distally with respect to the second staple leg 2132b, angle K can be smaller than angle H. The reader will appreciate that the first portion 2133b and the second portion 2134b are not collinear; rather, the first portion 2133b extends along a first axis 2137b and the second portion 2134b extends along a second axis 2138b which is different from the first axis 2137b. A joint 2135b interconnects the first portion 2133b and the second portion 2134b and is located a distance B measured from a support surface 2139 defined on the bottom of the base 2131. Distance B may or may not be the same as distance D. The second portion 2134b includes a leg tip 2136b which is located a distance A measured from the base support surface 2139. Distance A may or may not be the same distance as distance C. The first portion 2133b comprises a first cantilever extending from the base 2131 and the second portion 2134b comprises a second cantilever extending from the first portion 2133b. Distance B defines the first cantilever distance and the difference between distance A and distance B defines the second cantilever distance. The distance between the first tip 2136a ofthe first staple leg 2132a and the second tip 2136b of the second staple leg 2312 defines the spread distance between the staple legs 2132a, 2132b and is indicated by distance J. Distance J may or may not be wider than the crown distance E.

0046<figref idref="f0027">FIG. 25</figref> depicts the staple 2130 positioned within a staple cavity 2150 defined in a cartridge 2110 and supported by a staple driver 2040. The reader will appreciate that the legs 2132a and 2132b of the staple 2130 have been biased or flexed inwardly by the end walls of the staple cavity 2150. As a result, the distances A, B, C, D, E and J may have changed and are represented by A', B', C', D', E', and J', respectively. The staple 2130 consists of a resilient material, such as stainless steel and/or titanium, and the changes to these distances can be reversed, or at least partially reversed, when the staple 2130 is ejected from the staple cavity 2150. Similarly, the angles F, G, H, and K may have changed as a result of positioning the staple 2130 in the staple cavity 2150 and are represented by angles F', G', H', and K', respectively. As described above, the staple 2130 consists of a resilient material and the changes to these angles can be reversed, or at least partially reversed, when the staple 2130 is ejected from the staple cavity 2150. <figref idref="f0027">FIG. 25</figref> illustrates the staple 2130 and the driver 2040 in an unfired position. In this unfired position, the tip 2136a of the first staple leg 2132a extends above a deck surface 2111 of the cartridge 2110 and is positioned within and protected by a projection 2150a extending from the deck surface 2111 and, similarly, the tip 2136b of the second staple leg 2132b extends above the deck surface 2111 and is positioned within and protected by a projection 2150b extending from the deck surface 2111.

0047A staple 2230 is illustrated in <figref idref="f0028">FIG. 26</figref>. The staple 2230 comprises a base 2231, a first leg 2232a extending from the base 2231, and a second leg 2232b extending from the base 2231. The first leg 2232a comprises a first portion 2233a connected to the base 2231 and a second portion 2234a extending from the first portion 2233a. The second leg 2232b comprises a first portion 2233b connected to the base 2231 and a second portion 2234b extending from the first portion 2233b. The base 2231, the first portion 2233a, and the first portion 2233b comprise a generally V-shaped configuration. The second portion 2234a extends inwardly from the first portion 2233a at a joint 2235a and, similarly, the second portion 2234b extends inwardly from the first portion 2233b at a joint 2235b. The base 2231, the first leg 2232a, and the second leg 2232b are configured and arranged such that the staple 2230 is symmetrical in its unformed, or unfired, configuration illustrated in <figref idref="f0028">FIG. 26</figref>. The first leg 2232a is positioned distally with respect to the second leg 2232b. Alternatively, the first leg 2232a can be positioned proximally with respect to the second leg 2232b.

0048A staple 2330 is illustrated in <figref idref="f0028">FIG. 27</figref>. The staple 2330 comprises a base 2331, a first leg 2332a extending from the base 2331, and a second leg 2332b extending from the base 2331. The first leg 2332a comprises a straight portion 2333a connected to the base 2331 which extends along an axis. The second leg 2332b comprises a first portion 2333b connected to the base 2331 and a second portion 2334b extending from the first portion 2333b. The base 2331, the straight portion 2333a, and the first portion 2333b comprise a generally V-shaped configuration. The second portion 2334b extends inwardly from the first portion 2333b at a joint 2335b. The base 2331, the first leg 2332a, and the second leg 2332b are configured and arranged such that the staple 2330 is asymmetrical in its unformed, or unfired, configuration illustrated in <figref idref="f0028">FIG. 27</figref>. The first leg 2332a is positioned distally with respect to the second leg 2332b. Alternatively, the first leg 2332a can be positioned proximally with respect to the second leg 2332b.

0049A staple 2430 is illustrated in <figref idref="f0028">FIG. 28</figref>. The staple 2430 comprises a base 2431, a first leg 2432a extending from the base 2431, and a second leg 2432b extending from the base 2431. The first leg 2432a comprises a first portion 2433a connected to the base 2431 and a second portion 2434a extending from the first portion 2433a. The second leg 2432b comprises a first portion 2433b connected to the base 2431 and a second portion 2434b extending from the first portion 2433b. The base 2431, the first portion 2433a, and the first portion 2433b comprise a generally V-shaped configuration. The second portion 2434a extends inwardly from the first portion 2433a at a first angle at a joint 2435a and, similarly, the second portion 2434b extends inwardly from the first portion 2433b at a second angle at a joint 2435b. The first angle and the second angle can be different. The base 2431, the first leg 2432a, and the second leg 2432b are configured and arranged such that the staple 2430 is asymmetrical in its unformed, or unfired, configuration illustrated in <figref idref="f0028">FIG. 28</figref>. The first leg 2432a is positioned distally with respect to the second leg 2432b. Alternatively, the first leg 2432a can be positioned proximally with respect to the second leg 2432b.

0050A staple 2530 is illustrated in <figref idref="f0028">FIG. 29</figref>. The staple 2530 comprises a base 2531, a first leg 2532a extending from the base 2531, and a second leg 2532b extending from the base 2531. The first leg 2532a comprises a first portion 2533a connected to the base 2531 and a second portion 2534a extending from the first portion 2533a. The second leg 2532b comprises a first portion 2533b connected to the base 2531 and a second portion 2534b extending from the first portion 2533b. The base 2531, the first portion 2533a, and the first portion 2533b comprise a generally V-shaped configuration. The second portion 2534a extends inwardly from the first portion 2533a at a first angle at a joint 2535a and, similarly, the second portion 2534b extends inwardly from the first portion 2533b at a second angle at a joint 2535b. The first angle and the second angle can be different. The base 2531, the first leg 2532a, and the second leg 2532b are configured and arranged such that the staple 2530 is asymmetrical in its unformed, or unfired, configuration illustrated in <figref idref="f0028">FIG. 29</figref>. The staple 2530 is similar to the staple 2430 in many respects and includes a wider base 2531 than the base 2431. A wider staple base can be accommodated within a given staple cavity when the staple leg 2532a and/or the staple leg 2532b extend in directions which are closer to the vertical direction. The first leg 2532a is positioned distally with respect to the second leg 2532b. Alternatively, the first leg 2532a can be positioned proximally with respect to the second leg 2532b.

0051Tissue captured between an anvil and a staple cartridge of a surgical end effector can move within or flow relative to the end effector during use. This movement or flow can be generally distal as the firing member of the end effector is moved distally to fire the staples removably stored in the staple cartridge and incise the tissue. Were the firing member moved proximally, the movement or flow of the tissue would be generally proximal. Nonetheless, the distal flow of the tissue can shift the staples distally during the firing process. This phenomenon is depicted in <figref idref="f0029">FIG. 30. FIG. 30</figref> illustrates a staple 2630 being ejected from a staple cavity 2650 defined in a cartridge body 2610. The staple 2630 is illustrated in at least partially fired position wherein a base 2631 of the staple 2630 is being moved upwardly toward the anvil 20 by a staple driver 2640 and wherein legs 2632a, 2632b of the staple 2630 have emerged from the staple cavity 2650 and have contacted the anvil 20. As the reader will appreciate, the staple cavity 2650 includes a first projection 2651a and a first endwall 2652a which are configured to support the first staple leg 2632a and, similarly, a second projection 2651b and a second sidewall 2652b which are configured to support the second staple leg 2632b as the staple 2630 is ejected from the staple cavity 2650 by the driver 2640. As illustrated in <figref idref="f0029">FIG. 30</figref>, however, the staple 2630 can be shifted distally during the firing process such that the staple leg 2632a is shifted away from the first endwall 2652a and the staple leg 2632b is shifted over the second projection 2651b. Although the staple 2630 has been shifted distally, the first leg 2632a has still been received within a first forming cup 22a of a staple pocket defined in the anvil 20 and the second leg 2632b has still been received within a second forming cup 22b of the staple pocket. Although the staple legs 2632a, 2632b may contact their respective forming cups 22a, 22b, the distal shifting of the staple 2630 may not result in a symmetrically formed staple, as illustrated in <figref idref="f0029">FIG. 31. FIG. 31</figref> illustrates the staple 2630 lifted into a position above a cartridge deck surface 2611 of the cartridge body 2610 by the staple driver 2640 and deformed into its fully fired configuration.

0052As discussed above, symmetrical staples may be deformed asymmetrically as a result of being shifted by the tissue captured within an end effector. However, the staple cartridge can utilize asymmetrical staples, such as the asymmetrical staples illustrated in <figref idref="f0026">FIGS. 24</figref> and <figref idref="f0028">27-29</figref>, which can compensate for this shifting. The staple legs of these asymmetrical staples are configured in such a way that, when the asymmetrical staples are shifted distally, they are shifted into an orientation which causes them to be deformed into a symmetrical, or an at least more symmetrical, fired configuration. <figref idref="f0072">FIG. 84</figref> depicts a staple cartridge 4800 which comprises a cartridge body 4810 including a plurality of staple cavities 4850 defined therein, asymmetrical staples positioned within the staple cavities 4850, and a plurality of drivers 4840 configured to eject the staples from the staple cavities 4850. The cartridge body 4810 includes a distal end 4813 and a proximal end 4816 wherein the staple cavities 4850 are arranged in longitudinal rows defined in the cartridge body 4810. The cartridge body 4810 is cross-sectioned in <figref idref="f0072">FIG. 84</figref> in such a manner so as to depict one such longitudinal row of staple cavities 4850. The staples removably stored within a longitudinal row of staple cavities 4850 may have the same asymmetrical configuration or, as illustrated in <figref idref="f0072">FIG. 84</figref>, the staples may have different asymmetrical configurations. For instance, staples 4830' are stored in the proximal end of the longitudinal row while staples 4830" are stored in distal end of the longitudinal row. Each staple 4830' includes a first staple leg 4832a' and a second staple leg 4832b' wherein one or both of the staple legs include several segments, such as segments 4833b' and 4834b' of the second staple leg 4832b'. Each staple 4830" may also include a first staple leg 4832a" and a second staple leg 4832b" wherein one or both of the staple legs include several segments, such as segments 4833a" and 4834a" of the first staple leg 4832a" and segments 4833b" and 4834b" of the second staple leg 4832b'. Upon comparing staples 4830' and staples 4830", the reader will appreciate that the angle between the segments 4833b" and 4834b" of the staples 4830" is more pronounced, or larger, than the angle between the segments 4833b' and 4834b' of the staples 4830'. Thus, the distal staples 4830" can be more asymmetrical than the proximal staples 4830'. Tissue movement at the distal end 4813 of the staple cartridge 4800 can be larger than the tissue movement at the proximal end 4816 and, correspondingly, the shift in the staple orientations can be larger at the distal end 4813 ofthe staple cartridge 4800 than the proximal end 4816. The larger asymmetry of the distal staples 4830" compensates for the larger staple shifts as compared with the smaller asymmetry of the proximal staples 4830' which are subjected to smaller staple shifts. This is but one example and any suitable assortment of staples could be utilized within a staple row to compensate for different staple shifts. It is contemplated, that the staples located at the proximal end of a longitudinal row could have a larger asymmetry than the staples located at the distal end of the longitudinal row. It is also contemplated that a longitudinal row could utilize more than two groups of asymmetrical staples.

0053As mentioned above, the tissue movement or flow at the distal end of an end effector can be larger than the tissue movement or flow at the proximal end of the end effector. This can arise as a result of the distal movement of the firing member within the end effector. Although the firing member is configured to progressively staple and incise the tissue as it is moved distally, the firing member can also plow or push the tissue distally. This pushing or plowing effect begins at the proximal end of the end effector and compound as the firing member is moved distally such that the largest pushing or plowing effect is realized at the distal end of the end effector. Thus, a gradient in staple asymmetries may be utilized within a longitudinal staple row to compensate for a gradient in tissue movement and staple shifting.

0054In addition to or in lieu of the above, a staple cartridge could utilize projections having different heights to control the movement of tissue within an end effector. The projections disclosed herein which extend from a deck of a staple cartridge reduce the gap between the staple cartridge and the anvil of the end effector. As a result, the projections apply a larger localized pressure to the tissue positioned between the anvil and the staple cartridge as compared with the absence of projections. Projections having a taller height apply a larger compressive force or pressure to the tissue while projections having a shorter height apply a relatively smaller compressive force or pressure to the tissue. Along these lines, taller projections provide greater control over tissue movement than shorter projections. As the reader will recall, the tissue movement at the proximal end of an end effector may be less than the tissue movement at the distal end of the end effector and, as a result, referring again to <figref idref="f0072">FIG. 84</figref>, the staple cartridge 4800 can utilize shorter projections 4851' at the proximal end 4816 of the cartridge body 4810 and taller projections 4851" at the distal end 4813. As illustrated, the shorter projections 4851' extend a distance 4855' from a deck surface 4811 of the cartridge body 4810 and the taller projections 4851" extend a distance 4855" from the shorter projections 4851'. The projections extending from the cartridge body comprise a gradient of heights extending between a proximal end and a distal end of the cartridge body. As discussed above, the tallest projections of the gradient can be at the distal end of the cartridge body while the shortest projections of the gradient can be at the proximal end of the cartridge body. Alternatively, the tallest projections of the gradient can be at the proximal end of the cartridge body while the shortest projections of the gradient can be at the distal end of the cartridge body.

0055As discussed above, tissue movement can shift staples as they are being deployed from a staple cartridge. Taller projections provide greater control over such a shift than shorter projections. Referring again to <figref idref="f0072">FIG. 84</figref>, the taller distal projections 4851" can be arranged to extend the staple pockets 4850 more than the shorter proximal projections 4851' such that the staples 4830" are controlled by the distal projections 4851" for a longer distance than the staples 4830' are controlled by the proximal projections 4851'. The taller projections 4851" also increase the distance in which the staples 4830" are lifted upwardly before the legs of the staples 4830" emerge from the cavities 4850 as compared with the distance in which the staples 4830' are lifted upwardly before the legs of the staples 4830' emerge from the cavities 4850. Such an arrangement reduces the distance and/or time in which the staples 4830" are exposed to the larger tissue movements at the distal end of the staple cartridge 4800.

0056The staple cartridge can utilize more than one configuration of staple within a longitudinal staple row. For example, the staple cartridge can utilize staples having different configurations in different longitudinal staple rows. The staple cartridge includes staples having a first configuration in a first longitudinal staple row and a second configuration in a second longitudinal staple row. Turning now to <figref idref="f0040">FIGS. 49</figref> and <figref idref="f0041">49A</figref>, a staple cartridge 2700, comprises a plurality of longitudinal rows of staple cavities 2750 defined therein wherein the staple cavities 2750 defined in a first row each include a first staple 2730' (<figref idref="f0042">FIG. 50</figref>) removably stored therein, the staple cavities 2750 defined in a second row each include a second staple 2730" (<figref idref="f0042">FIG. 51</figref>) removably stored therein, and the staple cavities 2750 defined in a third row each include a third staple 2730"' (<figref idref="f0042">FIG. 52</figref>) removably stored therein. The first staples 2730' are positioned in the innermost longitudinal rows of staple cavities 2750, the second staples 2730" are positioned in the intermediate rows of staple cavities 2750, and the third staples 2730"' are positioned in the outermost longitudinal rows of staple cavities 2750. When the first staples 2730', having a first height A' (<figref idref="f0042">FIG. 50</figref>), and the second staples 2730", having a second height A" (<figref idref="f0042">FIG. 51</figref>) are in their unfired configurations, the second staples 2730" are taller than the first staples 2730'. Similarly, when the second staples 2730" and the third staples 2730"', having a third height A'" (<figref idref="f0042">FIG. 52</figref>), are in their unfired configurations, the third staples 2730'" are taller than the second staples 2730".

0057Each longitudinal row of staples is supported by a longitudinal row of staple drivers. For instance, a first longitudinal row of staple drivers supports a first row of first staples 2730', a second longitudinal row of staple drivers supports a second row of second staples 2730", and a third longitudinal row of staple drivers supports a third row of third staples 2730'". Referring to <figref idref="f0040">FIGS. 49</figref> and <figref idref="f0041">49A</figref>, a row of staple drivers 2742 supports a first row of first staples 2730' and a second row of staples 2730" such that each staple driver 2742 supports and fires at least one first staple 2730' and at least one second staple 2730". A row of staple drivers 2740 can also support a third row of third staples 2730"' such that each staple driver 2740 supports and fires at least one third staple 2730"'. The staple drivers 2742 each include a first cradle 2741' configured to support a first staple 2730' and a second cradle 2741" configured to support a second staple 2730" and, similarly, the staple drivers 2740 can each include a third cradle 2741'" configured to support a third staple 2730'". When the staple drivers 2740 and 2742 are in their unfired positions, as illustrated in <figref idref="f0041">FIG. 49A</figref>, the first cradles 2741' are supported at a first distance 2732' from a first row of forming pockets 23 defined in the anvil 20, the second cradles 2741" are supported at a second distance 2732" from a second row of forming pockets 23 defined in the anvil 20, and the third cradles 2741'" are supported at a third distance 2732"' from a third row of forming pockets 23 defined in the anvil 20. The first distance can be different from the second distance and/or the second distance can be different from third distance. As illustrated in <figref idref="f0040">FIG. 49</figref>, the first distance is shorter than the second distance and the second distance is shorter than the third distance. The first staples 2730', the second staples 2730", and/or the third staples 2730"' can be deformed to different formed heights when the drivers 2740 and 2742 are lifted toward the anvil 20 by a firing member 2760, to eject the staples 2730', 2730", and 2730"' from the staple cavities 2750. For instance, the innermost row of staples, i.e., staples 2730', can be formed to a first formed height, the intermediate row of staples, i.e., staples 2730", can be formed to a second formed height, and the outer row of staples, i.e., staples 2730'", can be formed to a third formed height. The first height can be shorter than the second height and the second height can be shorter than the third height.

0058The cartridge deck of a staple cartridge can be flat. In such cases, the projections described herein can extend from the flat deck surface. Alternatively, a cartridge deck of a staple cartridge can comprise a stepped surface including at least two stepped surfaces. Referring again to <figref idref="f0040">FIGS. 49</figref> and <figref idref="f0041">49A</figref>, the cartridge body 2710 of the staple cartridge 2700 includes a first deck side positioned on a first side of a longitudinal knife channel 2715 and a second deck side positioned on a second side of the longitudinal knife channel 2715. Each deck side comprises a first step 2711', a second step 2711", and a third step 2711'". The first longitudinal row of staple cavities 2750 is defined in the first step 2711', the second longitudinal row of staple cavities 2750 can be defined in the second step 2711", and the third longitudinal row of staple cavities 2750 can be defined in the third step 2711"'. When the anvil 20 is in its closed position, a tissue contacting surface 21 of the anvil 20 are positioned adjacent to the deck surface of the cartridge body 2710. In such circumstances, the tissue contacting surface 21 can be positioned a first distance 2712' away from the first step 2711', a second distance 2712" away from the second step 2711", and a third distance 2712'" away from the third step 2711 "'. The first distance, the second distance, and/or the third distance can be different. As illustrated in <figref idref="f0040">FIGS. 49</figref> and <figref idref="f0041">49A</figref>, the first distance 2712' is shorter than the second distance 2712" and the second distance 2712" is shorter than the third distance 2712'". The first distance 2712' defines a first tissue gap between the first step 2711' and the anvil 20, the second distance 2712" defines a second tissue gap between the second step 2711" and the anvil 20, and the third distance 2712"' defines a third tissue gap between the third step 2711'" and the anvil 20. The first tissue gap positioned over the innermost row of staple cavities 2750 is smaller than the third tissue gap positioned over the outermost row of staple cavities 2750. The second tissue gap positioned over the intermediate row of staple cavities 2750 is larger than the first tissue gap and smaller than the third tissue gap.

0059Referring again to <figref idref="f0040">FIGS. 49</figref> and <figref idref="f0041">49A</figref>, a first longitudinal row of projections 2751' extends from the first step 2711', a second longitudinal row of projections 2751" extends from the second step 2711", and a third longitudinal row of projections 2751'" extends from the third step 2711"'. The first projections 2751' are defined by a first height 2755', the second projections 2751" are defined by a second height 2755", and the third projections 2751'" are defined by a third height 2755"'. The first height, the second height, and/or the third height can be different. As illustrated in <figref idref="f0040">FIGS. 49</figref> and <figref idref="f0041">49A</figref>, the first height 2755' is shorter than the second height 2755" and the second height 2755" is shorter than the third height 2755'". The shortest longitudinal row of projections, i.e., projections 2751', extends along the innermost row of staple cavities 2750, the tallest longitudinal row of projections, i.e., projections 2751'", extends along the outermost row of staple cavities 2750, and the projections having an intermediate height, i.e., projections 2751", extends along the intermediate row of staple cavities 2750. <figref idref="f0065">FIG. 76</figref> illustrates an alternative embodiment in which the tallest longitudinal row of projections, i.e., projections 2751"', extends along the innermost row of staple cavities 2750, the shortest longitudinal row of projections, i.e., projections 2751', extends along the outermost row of staple cavities 2750, and the projections having an intermediate height, i.e., projections 2751" can extend along the intermediate row of staple cavities 2750.

0060Referring again to <figref idref="f0065">FIG. 76</figref>, a staple cartridge 4000 is shown that is similar to the staple cartridge 2700, in many respects. Similar to the staple cartridge 2700, the staple cartridge 4000 includes longitudinal rows of staple cavities 2750 comprising a first row of staple cavities 2750 including first staples 2730' removably stored therein, a second row of staple cavities 2750 including second staples 2730" removably stored therein, and a third row of staple cavities 2750 including third staples 2730'" removably stored therein. Here, the first row of staples 2730' is the outermost row of staples and the third row of staples 2730"' is the innermost row of staples. The staple cartridge 4000 includes drivers 4040 and 4042 which are configured to support the third staples 2730'" a third forming distance 2732"' from the anvil 20, the second staples 2730" a second forming distance 2732" from the anvil 20, and the first staples 2730' a first forming distance 2732' from the anvil 20 when the drivers 4040 and 4042 are in an unfired, or unlifted, position. The drivers 4040 and 4042 deform the innermost row of staples, i.e., staples 2730"', to a third formed height, the intermediate row of staples, i.e., staples 2730", to a second formed height, and the outermost row of staples, i.e., staples 2730' to a first formed height. The third formed height can be taller than the second formed height and the second formed height can be taller than the first formed height. Similar to the staple cartridge 2700, the staple cartridge 4000 includes a stepped deck surface; however, the third step 2711"' extends along the innermost row of staple cavities 2750 and the first step 2711' extends along the outermost row of staple cavities 2750. The first tissue gap defined by the first gap distance 2712' is positioned laterally outwardly with respect to the second tissue gap defined by the second gap distance 2712" which is positioned laterally outwardly with respect to the third tissue gap defined by the third gap distance 2712"'.

0061Another staple cartridge 3600 is illustrated in <figref idref="f0059 f0060 f0061">FIGS. 70-72</figref>. The staple cartridge 3600 includes a cartridge body 3610. The cartridge body 3610 comprises a distal end 3613, a proximal end 3616, and opposing lateral sides 3612. The cartridge body 3610 further includes a deck 3611, a plurality of staple cavities 3650 defined in the deck 3611, and a longitudinal slot 3615 configured to receive a knife edge of a firing member. The cartridge body 3610 further comprises projections 2051 and 2053 extending from the deck 3611. The cartridge body 3610 also comprises projections 3651 extending from the deck 3611. Similar to projections 2051, the projections 3651 are configured to engage tissue positioned between an anvil and the cartridge 3600 and control the movement of the tissue relative to the cartridge 3600. The projections 3651 are configured to limit or prevent the flow of the tissue relative to the staple cartridge. The projections 3651 can be positioned at the proximal end and/or the distal end of the staple cavities 3650. Each projection 3651 comprises a cuff extending around an end of a staple cavity 3650. Each projection 3651 can comprise an arcuate ridge extending around an end of a staple cavity 3650. The projections 3651 are not as tall as the projections 2051 and/or the projections 2053. The taller projections 2051 apply a larger localized pressure to the tissue than the shorter projections 3651. The projections 2051 provide sufficient control over the tissue to hold the tissue in position during the firing process. In such instances, the projections 3651 provide some additional control over the tissue in addition to protecting and guiding the staples positioned in the staple cavities 3650.

0062The deck 3611 includes steps 2711', 2711", and 2711"' which are configured to compress tissue positioned between the cartridge body 3610 and an anvil. The third step 2711'" comprises a lowermost deck surface which extends along the outermost rows of staple cavities 3650 and around the distal end 3613 of the cartridge body 2610. The second step 2711" sextend upwardly from the lowermost deck surface 2711'" and the first step 2711' extends upwardly from the second step 2711". When the cartridge body 3610 is slid relative to the tissue, the tissue can flow over the distal end 3613 of the cartridge body 3610 and onto the steps 2711', 2711", and 2711"'. The cartridge body 3610 further includes ramps 3614' and 3614" which are configured to assist the tissue in sliding onto the steps 2711' and 2711", respectively. As also discussed above, the steps 2711', 2711", and 2711"' are utilized to control the flow of tissue relative to the staple cartridge 3600. Referring primarily to <figref idref="f0060">FIG. 71</figref>, the step 2711' defines a smaller tissue gap between the cartridge 3600 and an anvil positioned opposite the cartridge 3600 as compared with the tissue gap defined between the step 2711" and the anvil and/or a tissue gap defined between the step 2711'" and the anvil. In the instances where the step 2711' and the smallest tissue gap are adjacent the longitudinal slot 3615, the tissue adjacent the longitudinal slot 3615 is subjected to more compression, and more control, than the tissue positioned laterally with respect to the step 2711'. This could be advantageous for a variety of reasons. For instance, a cutting member passing through the longitudinal slot 3615 may attempt to displace the tissue captured between the staple cartridge 3600 and the anvil and, as a result of the compression applied by the innermost step 2711', the displacement of the tissue is prevented, mitigated, or reduced.

0063As discussed above in connection with the embodiment depicted in <figref idref="f0065">FIG. 76</figref>, a staple cartridge can include a stepped deck surface in which the smallest tissue gap is co-extensive with the outermost longitudinal rows of staple cavities. In such instances, the smallest tissue gap may be adjacent the lateral sides of the cartridge and, as a result of the compression applied by the outermost steps, the displacement of the tissue, especially the lateral displacement of the tissue, is prevented, mitigated, or reduced. In certain instances, referring again to <figref idref="f0059 f0060 f0061">FIGS. 70-72</figref>, the lateral displacement of the tissue captured between the staple cartridge 3600 and an anvil can be prevented, mitigated, or reduced by lateral sidewalls 3617. As sown, each lateral sidewall 3617 extends from a lateral side 3612 of the cartridge body 3610 and blocks the lateral movement of the tissue. The sidewalls 3617 can comprise any suitable configuration. As shown, each sidewall 3617 comprises a scalloped top surface. Turning now to <figref idref="f0062">FIG. 73</figref>, a staple cartridge 3700 includes a cartridge body 3710 including lateral sidewalls 3717 extending from lateral sides 3712 of the cartridge body 3710. Each lateral sidewall 3717 includes a straight top surface.

0064Turning now to <figref idref="f0063">FIG. 74</figref>, a staple cartridge 3800 is shown that includes a cartridge body 3810 comprising a distal end 3813 and staple cavities 3850. The cartridge body 3810 includes projections 2053 at the distal ends of the distal-most staple cavities 3850. Also, the cartridge body 3810 includes projections 2051 which surround the proximal end and/or the distal end of at least some of the staple cavities 3850. In addition to or in lieu of the projections 2051 and 2053, the staple cartridge body 3810 can further include projections 3851 extending therefrom. Each projection 3851 extends around an end of more than one staple cavity 3850, e.g. each projection 3851can extend around an end of a staple cavity 3850 in an innermost row of staple cavities 3850, an end of a staple cavity 3850 in an outermost row of staple cavities 3850, and/or an end of a staple cavity 3850 in an intermediate row of staple cavities. A first portion of a projection 3851 could extend a first staple cavity 3850 above the cartridge deck surface, a second portion of the projection 3851 could extend a second staple cavity 3850 above the cartridge deck surface, and a third portion of the projection 3851 could extend a third staple cavity 3850 above the cartridge deck surface. The first portion of the projection 3851 protects, guides, and/or holds a first staple, the second portion protects, guides, and/or holds a second staple, and the third portion protects, guides, and/or holds a third staple. One such projection 3851 as shown extends between the longitudinal slot 3615 defined in the cartridge body 3810 and a lateral sidewall 3717 extending from the cartridge body 3810. A projection 3851 extends across a first step 2711', a second step 2711", and/or a third step 2711"'. Stated another way, a projection 3851 can extend across changes in elevation in the deck of the cartridge body 3810. The top, or tissue-engaging, surface of the projection 3851 can be flat despite the change in elevation of the cartridge deck surface. Alternatively, the top, or tissue-engaging, surface of the projection 3851 may also change in elevation. For example, the top surface of the projection 3851 can increase in elevation when the deck surface increases in elevation and decrease in elevation when the deck surface decreases in elevation. Alternatively, the top surface of the projection 3851 can decrease in elevation when the deck surface increases in elevation and increase in elevation when the deck surface decreases in elevation.

0065Referring again to <figref idref="f0063">FIG. 74</figref>, the cartridge body 3810 includes transverse projections, or ribs, 3817 extending therefrom. A transverse projection 3817 extends transversely to the longitudinal slot 3615 and/or the lateral sidewalls 3717. The transverse projection 3817 can extend in a direction which is perpendicular to the longitudinal slot 3615 and/or the lateral sidewalls 3717. The transverse projections 3817 may extend between the projections 3851 and the sidewalls 3717. The transverse projections 3817 may also extend between the projections 2051 and the sidewalls 3717 and, similarly, between the projections 2053 and the sidewalls 3717. The projections 3817 and the sidewalls 3717 can be the same height. Alternatively, the projections 3817 and the sidewalls 3717 can be different heights. Referring to <figref idref="f0063">FIG. 74</figref>, the sidewalls 3717 are taller than the projections 3817. In any event, the transverse projections 3817 are configured to limit or prevent the flow of the tissue relative to the staple cartridge 3800, especially in the distal or longitudinal direction.

0066Turning now to <figref idref="f0069">FIG. 81</figref>, a staple cartridge 4500 is shown that includes a cartridge body 4510 comprising a deck 4511, a proximal end, a distal end 4513, and a longitudinal knife slot 3615 extending between the proximal end and the distal end 4513. The cartridge body 4510 includes the sloped transition 2014, projections 2051, 2053, and 3651 at least partially surrounding staple cavities 3650, and lateral sidewalls 3617, among other features. In fact, it is envisioned that the tissue control features disclosed herein can be combined with other tissue control features disclosed herein. All of the staple cavities defined in the staple cartridge includes projections at least partially surrounding the staple cavities. Alternatively, less than all of the staple cavities can include such projections. Turning now to <figref idref="f0070">FIG. 82</figref>, a staple cartridge 4600 is shown that includes a cartridge body 4610 comprising a deck 4611, a proximal end 4616, a distal end 4613, and a longitudinal knife slot 4615 extending between the proximal end 4616 and the distal end 4613. The cartridge body 4610 includes projections 2051 and 2053 extending from the deck 4611 and at least partially surrounding some of the staple cavities 4650. For instance, the proximal and/or distal ends of the staple cavities 4650 defined in the distal end 4613 of the staple cartridge 4600 can be at least partially surrounded by the projections 2051 and, similarly, the proximal and/or distal ends of the staple cavities 4650 defined in the proximal end 4616 of the staple cartridge 4600 can be at least partially surrounded by the projections 2051. The staple cavities 4650 defined in the middle of the cartridge body 4610, i.e., between the proximal end 4616 and the distal end 4613 of the staple cartridge may not be surrounded by the projections 2051 and/or any other projections. Turning now to <figref idref="f0071">FIG. 83</figref>, a staple cartridge 4700 is shown that includes a cartridge body 4710 comprising a deck 4711, a proximal end, and a distal end 4713. The cartridge body 4710 includes a plurality of staple cavities 4750 defined therein. The distal-most staple cavities 4750 comprises a distal end surrounded by a projection 2053 and a proximal end surrounded by a projection 2051. Other staple cavities 4750 comprises a distal end surrounded by a projection 2051 and a proximal end that is not surrounded by a projection. Staple cavities 4750 can be arranged to have a proximal end surrounded by a projection 2051 and a distal end that is not surrounded by a projection.

0067As discussed above, projections extending from a deck surface can be configured to protect, support, and/or guide a staple positioned within a staple pocket. <figref idref="f0066">FIG. 77</figref> depicts a staple cartridge 4100 including a cartridge body 4110 including a deck 4111, a staple cavity 4150 defined in the deck 4111, and a projection 4151 extending from the deck 4111. The staple cartridge 4100 further comprises a staple 4130 removably positioned in the staple cavity 4150. The projection 4151 includes a slot 4154 defined therein which is configured to support a leg 4132 of the staple 4130 when the staple 4130 is stored in the staple cavity 4150 and/or when the staple 4130 is being ejected from the staple cavity 4150. The slot 4154 comprises an extension of a staple cavity end wall 4152. The staple cavity end wall 4152 and/or the slot 4154 co-operate to support the staple leg 4132 when the staple 4130 is in an unfired position. As the staple 4130 is ejected from the cavity 4150, the leg 4132 emerges from the projection 4151, as illustrated in <figref idref="f0066">FIG. 77</figref>. In such circumstances, the end wall 4152 and/or the slot 4154 support the portion of the staple 4130 that has not yet emerged from the staple cavity 4150. The projection 4151 may not provide lateral support to the staple leg 4132. More particularly, referring to <figref idref="f0066">FIG. 77</figref>, the slot 4154 can comprise opposing lateral sides 4155 which are spaced apart from, and not in contact with, the sides of the staple leg 4132. The staple 4130 may be deformed into its fully deformed configuration while the staple 4130 is still at least partially positioned in the staple cavity 4150. The end wall 4152 and/or the slot 4154 may support the staple 4130 throughout the entire forming process of the staple 4130. Alternatively, the staple 4130 may reach its fully deformed configuration after it has been lifted out of the slot 4154 and above the projection 4151. In such circumstances, the end wall 4152 and the slot 4154 may not support the staple 4130 during the entire forming process.

0068<figref idref="f0066">FIG. 78</figref> depicts a staple cartridge 4200 including a cartridge body 4210 including a deck 4211, a staple cavity 4250 defined in the deck 4211, and a projection 4251 extending from the deck 4211. The staple cartridge 4200 further comprises a staple 4130 removably positioned in the staple cavity 4250. The projection 4251 includes a slot 4254 defined therein which is configured to support a leg 4132 of the staple 4130 when the staple 4130 is stored in the staple cavity 4250 and/or when the staple 4130 is being ejected from the staple cavity 4250. The slot 4254 comprises an extension of a staple cavity end wall 4252. The staple cavity end wall 4252 and/or the slot 4254 co-operate to support the staple leg 4132 when the staple 4130 is in an unfired position. As the staple 4130 is ejected from the cavity 4250, the leg 4132 emerges from the projection 4251, as illustrated in <figref idref="f0066">FIG. 78</figref>. In such circumstances, the end wall 4252 and/or the slot 4254 support the portion of the staple 4130 that has not yet emerged from the staple cavity 4250. The projection 4251 may provide lateral support to the staple leg 4132. More particularly, referring to <figref idref="f0066">FIG. 78</figref>, the slot 4254 can comprise opposing lateral sides 4255 which are in contact with the sides of the staple leg 4132. The staple 4130 can be deformed into its fully deformed configuration while the staple 4130 is still at least partially positioned in the staple cavity 4250. The end wall 4252 and/or the slot 4254 may support the staple 4130 throughout the entire forming process of the staple 4130. Alternatively, the staple 4130 may reach its fully deformed configuration after it has been lifted out of the slot 4254 and above the projection 4251. In such circumstances, the end wall 4252 and the slot 4254 may not support the staple 4130 during the entire forming process.

0069<figref idref="f0067">FIG. 79</figref> depicts a staple cartridge 4300 including a cartridge body 4310 including a deck 4311, a staple cavity 4350 defined in the deck 4311, and projections 4351 extending from the deck 4311. The staple cartridge 4300 further comprises a staple 4130 removably positioned in the staple cavity 4350. Each projection 4351 includes a tapered slot 4354 defined therein which is configured to support a leg 4132 of the staple 4130 when the staple 4130 is stored in the staple cavity 4350 and/or when the staple 4130 is being ejected from the staple cavity 4350. Each slot 4354 comprises an extension of a staple cavity end wall 4352 and includes sidewalls 4355. The sidewalls 4355 of each slot 4354 co-operate to support the staple leg 4132 when the staple 4130 is in an unfired position. As the reader will appreciate from <figref idref="f0067">FIG. 79</figref>, the staple leg 4132 may not be supported by the end wall 4352. As the staple 4130 is ejected from the cavity 4350, the legs 4132 emerge from the projections 4351. The sidewalls 4355 of the slots 4354 support the portion of the staple 4130 that has not yet emerged from the staple cavity 4350. The sidewalls 4155 of the projections 4351 provide lateral support to the staple legs 4132. The staple 4130 may be deformed into its fully deformed configuration while the staple 4130 is still at least partially positioned in the staple cavity 4350. The slots 4354 may support the staple 4130 throughout the entire forming process of the staple 4130. Alternatively, the staple 4130 may reach its fully deformed configuration after it has been lifted out of the slots 4354 and above the projections 4351. In such circumstances, the slots 4354 may not support the staple 4130 during the entire forming process.

0070<figref idref="f0068">FIG. 80</figref> depicts a staple cartridge 4400 including a cartridge body 4410 including a deck 4411, a staple cavity 4450 defined in the deck 4411, and projections 4451a and 4451b extending from the deck 4411. The staple cartridge 4400 further comprises a staple 4130, removably positioned in the staple cavity 4450. The staple cavity 4450 comprises a first end wall 4452a configured to support and guide a first leg of the staple 4130 and a second end wall 4452b configured to support and guide a second leg of the staple 4130. The projection 4451a extends from the deck 4411 a first distance 4455a and the projection 4451b extends from the deck 4411 a second distance 4455b above the projection 4451a. As a result, the projection 4451a supports and guides the first staple leg a first distance and the projection 4451b supports and guides the second staple leg a second distance, wherein the second distance can be longer than the first distance. The projection 4451b can be positioned at the distal end of the staple cavity 4450 and the projection 4451a can be positioned at the proximal end of the staple cavity 4450. This may be advantageous when the staple 4130 is pushed distally by the distal movement of the firing member and the tissue knife, as discussed above. Alternatively, the projection 4451b can be positioned at the proximal end of the staple cavity 4450 and the projection 4451a can be positioned at the distal end of the staple cavity 4450. In any event, the projection 4451b may comprise a stepped configuration, for example the projection 4451b comprises a first portion defined by the height 4455a and a second portion defined by the height 4455b.

0071<figref idref="f0073">FIGS. 85A-85C</figref> illustrate a staple cartridge 4900 comprising a cartridge body 4910 including a deck 4911. The cartridge body 4910 can include a flexible material. The cartridge body 4910 can include a rigid material and a flexible material, wherein at least the deck 4911 can consist of the flexible material. A flexible material could include certain plastic materials, such as polypropylene, and/or an elastomeric material, such as rubber, a thermoplastic elastomer, and/or Santoprene. The deck 4911 can consist of a pliable material. In any event, the deck 4911 includes a projection 4951 extending therefrom. The projection 4951 protects, supports, and/or guides a staple 4130. Also, the projection 4951 can prevent or at least limit the movement of tissue relative to the staple cartridge 4900. When an anvil is moved into a closed position opposite the staple cartridge 4900 or, alternatively, the staple cartridge 4900 is moved into a closed position relative to an anvil, the projection 4951 can be compressed by the tissue positioned between the anvil and the staple cartridge 4900. <figref idref="f0073">FIGS. 85A-85C</figref> depict a sequence of events in which the projection 4951 is subjected to increasing compressive forces. <figref idref="f0073">FIG. 85A</figref> depicts the projection 4951 in an uncompressed configuration. In this configuration, a compressive or interference fit is present between the projection 4951 and the staple leg of the staple 4130. <figref idref="f0073">FIG. 85B</figref> depicts the projection 4951 in a compressed configuration in response to a compressive force being applied thereto. Upon comparing <figref idref="f0073">FIGS. 85A and 85B</figref>, it can be appreciated that a top surface 4956 of the projection 4951 has been pushed downwardly toward the deck 4911 a distance 4955 and that the shape of the projection 4951 has become distorted. In this configuration, the projection 4951 grips the staple leg of the staple 4130 and/or holds the staple leg in position. <figref idref="f0073">FIG. 85C</figref> depicts a larger compressive force being applied to the projection 4951. Upon comparing <figref idref="f0073">FIGS. 85B and 85C</figref>, it can be appreciated that the top surface 4956 of the projection 4951 has been pushed further downwardly toward the deck 4911 and that the shape of the projection 4951 has become further distorted. Moreover, in this configuration, the projection 4951 increases the gripping force being applied to the staple leg.

0072<figref idref="f0074">FIGS. 86A and 86B</figref> illustrate a staple cartridge 5000 comprising a cartridge body 5010 including a deck 5011. The cartridge body 5010 further comprises a plurality of staple cavities 5050 defined therein and a plurality of projections 5051 extending from the deck 5011 which are configured to protect, support, and/or guide staples 5030 removably positioned in the staple cavities 5050. The staple cartridge 5000 further includes staple drivers 5040 and 5042 which are configured to support and lift the staples 5030 between an unfired position and a fired position. <figref idref="f0074">FIGS. 86A and 86B</figref> illustrated the staples 5030 in a partially-fired position wherein the tips of the staples 5030 have partially emerged from the projections 5051. The cartridge body 5010 can include a flexible material. The flexible material could include certain plastic materials, such as polypropylene, and/or an elastomeric material, such as rubber, a thermoplastic elastomer, and/or Santoprene. The cartridge body 5010 can consist of a pliable material. When a compressive force is applied to the cartridge body 5010, the cartridge body 5010 can flex, as illustrated in <figref idref="f0074">FIG. 86B</figref>. When the deck 5011 ofthe cartridge body 5010 is flexed downwardly, as illustrated in <figref idref="f0074">FIG. 86B</figref>, the projections 5051 are deflected downwardly a distance 5055. In this way, the projections 5051 are movable.

0073It is envisioned that projections extending from a staple cartridge deck can move relative to the deck. Such a projection can move between a first position in which the projection extends a staple cavity above the deck and a second, or lowered, position in which the projection may or may not extend the staple cavity above the deck. One or more of the projections extending from a deck can be collapsible. A collapsible projection can move between a first position in which the projection extends a staple cavity above the deck and a second, or collapsed, position in which the projection may or may not extend the staple cavity above the deck. The collapsible projections may resiliently return to their uncollapsed configuration or, alternatively, the projections may not completely return to their uncollapsed configuration. One or more projections extending from a deck can be crushable. A crushable projection can move between a first position in which the projection extends a staple cavity above the deck and a second, or crushed, position in which the projection may or may not extend the staple cavity above the deck. The crushable projections do not return to their uncrushed configuration.

0074As discussed above, the staples of a staple cartridge are supported by staple drivers when the staples are removably stored in the staple cartridge. As also discussed above, the staple drivers can be lifted upwardly by a firing member, such as firing member 2760. Turning now to <figref idref="f0043">FIGS. 53 and 54</figref>, the firing member is configured to advance a staple sled, such as staple sled 2870, distally to lift the staple drivers and the staples toward the anvil. The staple sled 2870 comprises a body 2871 and a shoulder 2876 which are configured to be engaged by and support the firing member 2760. The sled 2870 further comprises ramped or inclined surfaces 2872, 2873, 2874, and/or 2875, which are configured to slide under the staple drivers and lift the staple drivers upwardly as the sled 2870 slides under the staple drivers. The first ramp surface 2872 is configured to contact and lift staple drivers in a first row of staple drivers, the second ramp surface 2873 is configured to contact and lift staple drivers in a second row of staple drivers, the third ramp surface 2874 is configured to contact and lift staple drivers in a third row of staple drivers, and the fourth ramp surface 2875 is configured to contact and lift staple drivers in a fourth row of staple drivers.

0075The sled 2870 is configured to simultaneously lift a staple driver in four rows of staple drivers. The sled 2870 may be arranged to synchronously lift the staple drivers in the four rows of staple drivers. In such cases, the distal ends of the four ramp surfaces 2872, 2873, 2874, and 2875 are configured to contact the four staple drivers at the same time and lift them along four parallel lift surfaces such that the staple drivers reach the same height at the same time. Also, the ramp surfaces 2872, 2873, 2874, and 2875 can all have the same length. Alternatively, the sled 2870 can simultaneously lift a staple driver in each of the four rows of staple drivers, albeit in a staggered manner. Referring primarily to <figref idref="f0043">FIG. 54</figref>, the distal end 2872a of the first ramp 2872 is aligned with the distal end 2875a of the fourth ramp 2875. The first ramp 2872 is parallel to the fourth ramp 2875. Moreover, the first ramp 2872 defines a first ramp length which is the same as a fourth ramp length defined by the fourth ramp 2875. The distal end 2873a of the second ramp 2873 is positioned distally with respect to the distal end 2872a of the first ramp 2872 and the distal end 2875a of the fourth ramp 2875 by a distance indicated by distance 2879a. The second ramp 2873 is not parallel to the first ramp 2872 and/or the fourth ramp 2875. Moreover, the second ramp 2873 defines a second ramp length which is longer than the first ramp length and/or the fourth ramp length. The distal end 2874a of the third ramp 2874 is positioned distally with respect to the distal end 2873a of the second ramp 2873 by a distance indicated by distance 2878a. The third ramp 2874 is not parallel to the first ramp 2872, the second ramp 2873, and/or the fourth ramp 2875. Moreover, the third ramp 2874 defines a third ramp length which is longer than the first ramp length, the second ramp length, and/or the fourth ramp length.

0076When a sled contacts a staple driver, a reactionary force and/or torque can be created between the sled and the staple driver which can cause the sled and/or the staple driver to rotate in response to the reactionary force and/or torque. The arrangement of ramps depicted in <figref idref="f0043">FIGS. 53 and 54</figref> prevents, or at least limits, the rotation of the sled 2870 when the sled 2870 contacts and lifts the staple drivers. Moreover, the sled 2870 includes a stabilizing member 2877 which extends distally to stabilize the sled 2870 and prevent and/or inhibit the rocking or rotation of the sled 2870. The stabilizing member 2877 extends distally with respect to the distal ends 2872a, 2873a, 2874a, and 2875a of the ramps 2872, 2873, 2874, and 2875.

0077Turning now to <figref idref="f0044 f0045">FIGS. 54A-54D</figref>, the sled 2870 is configured to deploy staples from staple cartridge 2000, when the sled 2870 is moved from the proximal end 2016 of the staple cartridge 2000 toward the distal end 2013 of the staple cartridge 2000. The staple cartridge 2000 and/or the sled 2870 include features which releasably hold the sled 2870 in the proximal end 2016 of the staple cartridge 2000. The cartridge body 2010 of the staple cartridge 2000 includes detents 2019 configured to engage the sled 2870 and releasably hold the sled 2870 in its proximal, unfired position, as illustrated in <figref idref="f0044">FIG. 54A</figref>. Referring primarily to <figref idref="f0044">FIGS. 54B</figref> and <figref idref="f0045">54C</figref>, each detent 2019 as illustrated comprises a rib, or ridge, which extends inwardly into the longitudinal slot 2015. The ridge extends vertically within the longitudinal slot 2015. The body 2871 of sled 2870 is positioned within the longitudinal slot 2015 and is engaged with the detents 2019 when the sled 2870 is in its proximal, unfired position, as illustrated in <figref idref="f0044">FIG. 54A</figref>. The detents 2019 define a gap which is smaller than the width of the body 2871. In such instances, an interference fit is present between the detents 2019 and the body 2871 of the sled 2870 such that the detents 2019 grip and retain the sled 2870 in position. When a firing member pushes the sled 2870 distally, the body 2871 is pushed out of engagement with the detents 2019 and the sled 2870 can be advanced distally to fire the staples stored in the staple cartridge 2000. Referring now to <figref idref="f0045">FIG. 54D</figref>, the body 2871 of the sled 2870 comprises grooves 2018 defined therein which are configured to releasably receive the detents 2019. The grooves 2018 and the detents 2019, when aligned, define the proximal, unfired position of the sled 2870. Although two sets of grooves 2018 and detents 2019 are present in the illustrated embodiment, a single set could be utilized to releasably hold the sled 2870 in position. Alternatively, more than two sets of grooves 2018 and detents 2019 could be utilized. The detents 2019 may extend from the body 2871 of the sled 2870 and the grooves 2018 may be defined in the cartridge body 2010.

0078As discussed above, the cartridge body can comprise a tissue-supporting deck and projections extending from the deck which are configured to, one, control the flow of tissue relative to the cartridge body, two, extend the staple cavities defined in the cartridge body above the deck and/or, three, support, protect, and/or guide the staples in the staple cavities. The cartridge body and the projections can consist of a unitary piece of material. Thus, the projections can be integrally formed with the cartridge body. The cartridge body and the projections can consist of a plastic material and can be formed by an injection molding process. In certain cases, the projections can be assembled to the cartridge body, for example adhered to the cartridge body. The cartridge body and the projections may consist of the same material or different materials. For example, the cartridge body can consist of a plastic material and the projections can be formed from an elastomeric material, such as rubber, a thermoplastic elastomer, and/or Santoprene. The projections can consist of a pliable material and may be such as not to traumatize the tissue compressed by the projections. Projections 3051 (<figref idref="f0051">FIG. 60</figref>) and/or projections 3151 (<figref idref="f0052">FIG. 61</figref>), may consist of an elastomeric material, such as rubber, a thermoplastic elastomer, and/or Santoprene. The cartridge body can be formed by a plastic injection molding process and the projections can be formed on the cartridge body during a second molding process using a material which is more pliable than the material constituting the cartridge body. The projections 3051 and/or 3151, can comprise a textured deck surface. These projections 3051 and/or 3151, can consist of a material which has a higher coefficient of friction than the cartridge body. This can improve the gripping force between the cartridge body and the tissue.

0079The projections extending from a cartridge body can be static and they may not move relative to the cartridge body. Alternatively, the projections can be flexible and can deform relative to the cartridge body. Also, the cartridge body can be flexible which permits the projections to move when the cartridge body deflects. Turning now to <figref idref="f0064">FIG. 75</figref>, a staple cartridge 3900 comprises a cartridge body 3910 comprising a plurality of cavities 3950 defined therein. A cavity 3950 comprises a deployable tissue-engaging member 3940 positioned therein. Each member 3940 can be moved from an undeployed position to a deployed position. When a member 3940 is in its undeployed position, the member 3940 does not extend above the deck 3911 and, when the member 3940 is in its deployed position, the member 3940 extends above the deck 3911. Alternatively, the member 3940 can extend above the deck 3911 when it is in its undeployed position. For example, the tissue-engaging member 3940 can engage the tissue in its undeployed position and its deployed position. In any event, the member 3940 comprises projections 3951 extending therefrom which are configured to engage, stabilize, and/or compress tissue positioned between the anvil 20 and the cartridge 3900.

0080Referring again to <figref idref="f0064">FIG. 75</figref>, the members 3940 can be deployed by a sled 3970 which traverses the cartridge body 3910 longitudinally from a proximal end to a distal end thereof. The sled 3970 comprises a ramp 3972 which is configured to sequentially engage the members 3940 and lift the members 3940 between their undeployed positions and their deployed positions. Each member 3940 comprises a beveled or angled surface 3942 which is contacted by the ramp 3972. The ramp 3972 slides underneath the members 3940 and lifts the members 3940 onto a surface 3979. The surface 3979 holds the members 3940 in their deployed positions as the sled 3970 is advanced distally by the firing member 2760. As illustrated in <figref idref="f0064">FIG. 75</figref>, the surface 3979 is long enough to support several members 3940 thereon. Moreover, the surface 3979 is long enough the support the members 3940 during the staple forming and tissue cutting processes performed by the firing member 2760. The surface 3979 leads, or is positioned distally with respect to, the knife edge 2761 ofthe firing member 2760. The members 3940 hold the tissue positioned distally with respect to the knife edge 2761 as the knife edge 2761 is moved distally through the tissue. Stated another way, the tissue-engaging members 3940 can be deployed to grip a portion of tissue in advance of the tissue portion being stapled and/or incised. The cavities 3950 are configured to support and guide the members 3940 and inhibit the members 3940 from being translated laterally or rotated within the cavities 3950. The proximal end of the surface 3979 is configured and arranged such that the sled 3970 releases a member 3940 once the knife edge 2761 has passed the member 3940. Thus, the surface 3979 may no longer support a member 3940 once the knife edge 2761 has slid by the member 3940.

0081Referring again to <figref idref="f0064">FIG. 75</figref>, the cavities 3950 are arranged in longitudinal rows. For instance, the cavities 3950 can be arranged in six longitudinal rows comprising two innermost rows, two outermost rows, and a row positioned between each innermost row and outermost row. Other embodiments are envisioned in which the cavities 3950 are arranged in fewer than six rows or more than six rows. In any event, some of the cavities 3950 defined in the cartridge body 3910 are configured to support and guide a member 3940, as discussed above, while some of the cavities 3950 contain a staple 2630, removably stored therein. The sled 3970 is configured to deploy the members 3940 and, in addition, fire the staples. The sled 3970 further comprises at least one ramp 2873 including a ramp surface 3971 configured to lift staple drivers 2640, toward the anvil 20 which, as discussed above, fires the staples 2630. The ramp 3972 leads the ramp 2873. In such instances, the ramp 3972 deploys a member 3940 into its deployed position before the ramp 2873 lifts the staples adjacent the member 3940 into their fully-formed positions. It is envisioned that the outermost rows of cavities 3950 include tissue-engaging members 3940 stored therein and the innermost rows and the intermediate rows of cavities 3950 include staples removably stored therein. Such an arrangement may include two rows of staples and one row of tissue-engaging members 3940 on each side of the longitudinal knife slot defined in the cartridge body. Other possibilities are envisioned in which any suitable arrangement of members 3940 and staples could be utilized.

0082As discussed above, the staple cartridge can include rows of staples and rows of deployable tissue-engaging members. The deployable tissue-engaging members can be arranged so as not to be interspersed within a staple row. Alternatively, deployable tissue-engaging members may be dispersed within a staple row. It is also envisioned that the staple cavities are used to store deployable tissue-engaging members. Nonetheless, the tissue-engaging members may not be stored within staple cavities and can instead be stored within a row of cavities adjacent to the staple cavities.

0083<figref idref="f0078 f0079 f0080">FIGS. 90-93</figref> illustrate deployable tissue-engaging projections. A staple cartridge 5300, comprises a cartridge body 5310 including a deck 5311 and a plurality of staple cavities 5350 defined therein. The staple cartridge 5310 includes staples 5330 removably stored within the staple cavities 5350 and a plurality of drivers 5340 configured to eject the staples 5330 from the staple cavities 5350. The staple cartridge 5310 further includes one or more deployable projections 5351 removably stored in the staple cavities 5350, as will be discussed in greater detail further below. Each driver 5340 includes a cradle 5341 configured to support a staple 5330 and, in addition, a drive surface 5342 configured to be engaged by a sled, such as sled 5370. The sled 5370 is configured to lift the drivers 5340 between an undeployed position and a deployed position. <figref idref="f0079">FIG. 92</figref> depicts the drivers 5340 and the staples 5330 in their undeployed positions. Referring primarily to <figref idref="f0080">FIG. 93</figref>, the drivers 5340 are configured to lift the deployable projections 5351 between an undeployed position and a deployed position. Referring primarily to <figref idref="f0078">FIGS. 90 and 91</figref>, each driver 5340 is assembled between a first deployable projection 5351 positioned around a proximal end of the driver 5340 and a second deployable projection 5351 positioned around a distal end of the driver 5340 wherein the upward movement of the driver 5340 can be transferred to the deployable projections 5351 to move the projections 5351 to their deployed positions. The projections 5351 may be frictionally engaged with the drivers 5340. When the drivers 5340 are lifted upwardly, the friction fit between the drivers 5340 and the projections 5351 lifts the projections 5351 upwardly. Each projection 5351 comprises a tissue-engaging portion 5352 which is configured to contact the tissue and apply a compressive force to the tissue. A projection 5351 applies a compressive force to the tissue until the compressive force exceeds the static friction force between the projection 5351 and the driver 5340 moving the projection 5351 upwardly. At such point, the driver 5340 moves or slips relative to the projection 5351. Stated another way, the driver 5340 decouples from the projections 5341 associated therewith.

0084Referring again to <figref idref="f0080">FIG. 93</figref>, the tissue-engaging portions 5352 of the deployable projections 5351 do not extend above the deck 5311 when the projections 5351 are in their undeployed position. Alternatively, the tissue-engaging portions 5352 of the deployable projections 5351 may extend above the deck 5311 when the projections 5351 are in their undeployed position. In either event, the tissue-engaging portions 5352 of the deployable projections 5351 extend above the deck 5311 when the projections 5351 are in their deployed position. The friction fit between each projection 5351 and a driver 5340 can be the same such that the force in which the driver 5340 will slide relative to a projection 5351, i.e., the slip force, is the same for each projection 5351. Other possibilities are envisioned in which the friction fit between certain projections 5351 and certain drivers 5340 can be different from other projections 5351 and other drivers 5340. In such cases, the slip force between the projections 5351 and the drivers 5340 are different. The first projection 5351 positioned at a distal end of a driver 5340 can begin to slip at a first slip force and the second projection 5351 positioned at a proximal end of a driver 5340 can begin to slip at a second slip force which is different from the first slip force. As a result of the above, the compressive force which a projection 5351 applies to the tissue can be limited. Moreover, the distance by which a projection 5351 extends from the deck 5311 of the cartridge body 5310 can be limited. The projections 5351 can exhibit a variable response to the type of tissue and/or the thickness of tissue being stapled. For instance, the projections 5351 may be deployed further from the deck 5311 when the tissue is thinner and/or more pliable as compared with when the tissue is thicker and/or more rigid. In any event, the slip fit between the driver 5340 and the projections 5351 prevents the tissue from being overcompressed by the projections 5351.

0085The projections 5351 can float relative to the cartridge deck 5311. The projections 5351 can be dynamically responsive to the compressive pressure created within the tissue captured between the anvil 20 and the staple cartridge 5300. For example, the firing member 2760 can cam or move the anvil 20 toward the staple cartridge 5300 as the firing member 2760 is advanced distally. When the anvil 20 is moved toward the staple cartridge 5300, the tissue is compressed by the anvil 20 and, in response, the projections 5351 move or retract downwardly into the cartridge body 5310.

0086A staple cartridge can comprise projections which extend rigidly from a deck of the cartridge body. The deck and the projections may be such as not to move relative to one another. Alternatively, the deck can move relative to the projections. For example, the projections can extend rigidly from the cartridge body and the deck can comprise a movable surface. When tissue is compressed between an anvil and such a staple cartridge, the deck moves downwardly with respect to the projections. The deck can move between a first position and a second position; in the first position, the projections do not extend above a top surface of the deck. In such cases, the projections can be recessed below the top surface of the deck when the deck is in its first position. When the deck is moved into its second position, the projections are exposed and extend above the top surface of the deck. Alternatively, the projections can extend above the top deck surface when the deck is in its first position and its second position. In either event, the distance which the deck is moved relative to the projections is a function of the pressure applied to the tissue. For instance, the deck may move a larger distance when a larger compressive pressure is applied to the tissue and a smaller distance when a smaller compressive pressure is applied to the tissue. The top deck surface can float in response to the compressive pressure applied thereto. It is envisioned that the deck comprises a unitary piece of material. Alternatives are possible in which the deck comprises a plurality of portions. For example, each portion can react independently of the other portions. The deck can consist of a resilient material which can deflect in response to the compressive pressure applied thereto. For example, the deck can consist of foam, or of oxidized regenerated cellulose. The deck can include apertures defined therein which permit relative movement between the deck and the projections. For example, the apertures can be through holes and the projections can be positioned within the through holes. An aperture can comprise a clearance slot which extends around a staple cavity and the projection, or projections, extending around the staple cavity. When the staples are ejected from the staple cavities, the staples pass through the openings provided by the clearance slots. In some instances, at least a portion of the deck can be captured by the staples to implant the deck against the tissue being stapled.

0087A staple cartridge disclosed herein can comprise an adjunct material. An adjunct material may be at least one layer of material which is positioned over the deck of the staple cartridge and is implanted into the patient by staples deployed from the staple cartridge. The at least one layer of material can be buttress material and/or a tissue thickness compensator. The at least one layer of material can consist of Gore SeamGuard material, Synovis Peri-Strips material, and/or polyurethane. Numerous references disclose such layers: <patcit id="pcit0005" dnum="US20130161374A"><text>U.S. Patent Publication No. 2013/0161374</text></patcit>, <patcit id="pcit0006" dnum="US20120318842A"><text>U.S. Patent Publication No. 2012/0318842</text></patcit>, <patcit id="pcit0007" dnum="US20120318843A"><text>U.S. Patent Publication No. 2012/0318843</text></patcit>, <patcit id="pcit0008" dnum="US20120312860A"><text>U.S. Patent Publication No. 2012/0312860</text></patcit>, and <patcit id="pcit0009" dnum="US20120318844A"><text>U.S. Patent Publication No. 2012/0318844</text></patcit>. The layers can consist of a bioabsorbable material and/or a non-bioabsorbable material. In some instances, a layer of material can be attached to the deck. For example, at least one adhesive can be utilized to releasably adhere the layer to the deck, or the layer of material can be releasably attached to the deck utilizing one or more sutures or straps. The layer can be a solid piece of material or it can include apertures defined therein. For example, a layer could be utilized with the staple cartridge 2000, that includes apertures, slits, and/or slots, defined therein which are aligned with the projections 2051 and/or projections 2053 extending from the deck 2011 of the staple cartridge 2010. These apertures may be through holes or windows extending completely through the layer. The apertures, slits, and/or slots, can be cut into a layer utilizing a bladed cutting member, formed when the layer is molded, or formed in the layer utilizing a laser cutting process. In some cases, the apertures can be recesses defined in the layer which do not extend completely through the layer. The projections can be closely received within the apertures such that relative movement between the cartridge body 2010 and the layer is prevented or at least limited. For example, an interference fit can be present between the projections and the sidewalls of the apertures.

0088Further to the above, an adjunct layer can consist of a woven layer and/or a non-woven layer. A layer can consist of film. A layer can include a textured surface, projections, and/or protrusions, extending therefrom which are configured to prevent or at least limit the flow of tissue relative to the staple cartridge. A layer can comprise a first set of regions which are engaged by and/or captured within the staples ejected from the staple cartridge and a second set of regions which are not engaged by or captured within the staples. The second set of regions can be modified. For example, a layer can consist of film and the second set of regions of the film can be modified to include apertures, slits, and/or slots. For example, a perimeter of such a layer can comprise cuts defined therein which can soften the edges of the layer. In certain instances, a pattern of cuts can be made in the layer. For example, the pattern of cuts can comprise cuts which extend at a 45 degree angle relative to one another. In some instances, the depth, width, and/or spacing of the cuts can be random. The cuts described above can make a layer of film more flexible, stretchable, and/or compliant. The cuts described above could be made to a woven or a non-woven material. The cuts described above can be made using any suitable process, such as by a mechanical blade system and/or a laser cutting system. The first set of regions of a layer may not be modified as discussed above.

0089As discussed above, a layer comprised of a solid piece of material can be modified to make the layer more flexible, stretchable, and/or compliant. A layer could be assembled from several pieces of material which are bonded together. For example, apertures, slits, and/or slots, can be present between the bonded pieces of material. In certain instances, strips of a highly non-elastic absorbable polymer could be welded into a thinner, more flexible film to provide stretch in certain intended directions and limit stretch in others. Such strips could also be used to reinforce highly-stressed parts of the film while allowing the other parts of the film to remain soft and compliant. One way to accomplish this would be to make several thin strips comprised of a harder polymer, such as Vicryl. These strips could be approximately 0.015" to 0.030" wide, and extend the full length of a staple line. Six strips could be arranged to correspond to the staple line lateral spread of six longitudinal staple rows. Then, a thin, continuous film layer approximately 0.003" to 0.005" thick, comprised of a soft and elastic polymer, such as Monocryl or 36/64 PGA/PCL, could be welded to the six strips. In some instances, a compression molding operation could be utilized. The result would be a highly-reinforced staple line with soft sides and the ability to readily stretch laterally, but not longitudinally. The strips extending from the film could even result in traction-like holding features that would minimize tissue flow over the film in the desired direction. In certain instances, a layer comprised of a woven and/or non-woven material can be modified so as to solidify certain regions of the layer, such as the first set of regions. A flat extruded fiber could be woven into a strip and then, through the use of felting and/or another heat-based technique, the first set of regions, could be fused together to solidify them. In some instances, the entirety of the layer could be fused together.

0090As discussed above, a staple cartridge may include projections extending from a cartridge body. In addition to or in lieu of these projections, the anvil can comprise projections extending therefrom which are configured to, one, control the flow of tissue relative to the anvil and the cartridge body, two, extend the staple cavities from the opposite side of the tissue and/or, three, support and/or guide the staples as they are being ejected from the staple cavities.

0091Such an anvil 3320 is illustrated in <figref idref="f0055">FIGS. 66</figref> and <figref idref="f0056">67</figref>. The anvil 3320 comprises a distal end 3323, a proximal end 3326, and a tissue-engaging surface 3321. The anvil 3320 further comprises a pivot 3327 about which the anvil 3320 can be rotated between an open position and a closed position. The anvil 3320 further comprises a longitudinal slot 3325 defined therein which is configured to receive a portion of a firing and/or cutting member therein. The anvil 3320 also comprises lateral sides which include a longitudinal projection, or wall, 3323 extending therefrom. The longitudinal wall 3323 comprises a scalloped surface. In some instances, the longitudinal wall 3323 comprises a flat surface. The walls 3323 are configured to limit or block the flow of tissue laterally with respect to the anvil 3320.

0092The anvil 3320 includes a plurality of staple forming pockets 3322 defined therein which are arranged in longitudinal rows which are registerable with the staple cavities defined in a staple cartridge. For instance, the forming pockets 3322 are arranged in innermost rows 3328a, outermost rows 3328c, and rows 3328b intermediate the innermost rows 3328a and the outermost rows 3328c. Each staple forming pocket 3322 comprises a first, or distal, forming cup 3322a and a second, or proximal, forming cup 3322b. The first forming cup 3322a is configured to receive and deform a first leg of a staple and the second forming cup 3322b is configured to receive and deform a second leg of the staple. The first forming cup 3322a and the second forming cup 3322b are separated by a flat 3322c. The anvil 3320 further comprises tissue-engaging projections 3324. The projections 3324 are positioned between the first forming cup 3322a and the second forming cup 3322b. A first projection 3324 is positioned on a first lateral side of the flat 3322c and a second projection 3324 is positioned on a second lateral side of the flat 3322c. The projections 3324 extending from the anvil 3320 co-operate with projections extending from a staple cartridge to guide and support the staples being ejected from the staple cartridge. For example, the anvil projections 3324 and the staple cartridge projections can interlock. The cartridge projections can extend from the ends of a staple cavity while the anvil projections 3324 can be positioned between the cartridge projections over the middle of the staple cavity. The anvil projections 3324 and the cartridge projections co-operate to extend a staple cavity and support and guide a staple while the staple is being formed against the anvil 3320. The cartridge projections extending from the ends of a staple cavity support and guide the legs of the staple as the staple legs emerge from the staple cavity and contact the anvil 3320. As the staple legs are being deformed within the forming cups 3322a, 3322b, the staple legs are supported and guided by the projections 3324 extending from the anvil. The staple legs are supported and guided by the cartridge projections and the anvil projections 3324 at the same time. In some cases, however, the staple legs maybe supported and guided by the cartridge projections and the anvil projections 3324, but not at the same time.

0093The forming cups 3322a, 3322b are configured to receive at least a portion of the projections extending from the staple cartridge therein. For example, each forming cup 3322a, 3322b comprises a wide, outer end configured to receive a projection extending from a staple cartridge and a narrow, inner end. The wide, outer end of the forming cups 3322a, 3322b is also configured to initially receive the staple legs. The forming cups 3322a, 3322b further include curved surfaces configured to direct the staple legs toward the narrow, inner ends of the forming cups 3322a, 3322b. The staple legs then exit the forming cups 3322a, 3322b from the narrow, inner ends, where the projections 3324 are situated to support and guide the staple legs. Each forming cup 3322a, 3322b includes angled surfaces intermediate the wide, outer end and the narrow, inner end. The angled surfaces guide the staple legs within the forming cups 3322a, 3322b, limit the lateral movement of the staple legs, and improve the alignment of the staple legs with the narrow, inner ends.

0094The projections 3324 are configured to engage tissue and hold the tissue in position while the tissue is being stapled and/or transected. Each projection 3324 comprises a plateau extending from the tissue-engaging surface 3321 which includes a flat surface. <figref idref="f0077">FIG. 89</figref> depicts an alternative comprising an anvil 5220 including forming pockets 3322 defined therein and tissue-engaging projections 5224 extending therefrom. Similar to projections 3224, each projection 5224 comprises a plateau portion 5224a and a flat surface 5224b configured to engage the tissue. In addition, each projection 5224 comprises a transition surface 5224c intermediate the plateau portion 5224a and the flat surface 5224c. The transition surface 5224c comprises a radius or a bevel.

0095Another anvil 5120 is illustrated in <figref idref="f0075">FIGS. 87</figref> and <figref idref="f0076">88</figref>. The anvil 5120 comprises a distal end 5123, a proximal end 5126, and a tissue-engaging surface. The tissue-engaging surface comprises steps. For instance, the tissue-engaging surface comprises a first step 5121' and a second step 5121". The second step 5121" can be taller than the first step 5121' and can extend from the first step 5121'. The anvil 5120 further comprises a pivot 3327 about which the anvil 3320 can be rotated between an open position and a closed position. The anvil 5120 further comprises a longitudinal slot 5125 defined therein which is configured to receive a portion of a firing and/or cutting member therein. The anvil 5120 also comprises lateral sides 5123 which may or may not include a longitudinal projection, or wall, extending therefrom. The taller second step 5121" is adjacent the longitudinal slot 5125 while the first step 5121' is adjacent the lateral sides 5123. The second step 5121" applies a larger compressive force to the tissue than the first step 5121'. Alternatively, the taller second step 5121" can be adjacent the lateral sides 5123 while the first step 5121' is adjacent the longitudinal slot 5125. While the anvil 5120 comprises two steps, the anvil 5120 could comprise more than two steps. In any event, the anvil 5120 comprises a ramp surface 5128" extending between the first step 5121' and the second step 5121" which facilitates the positioning of the anvil 5120 relative to tissue.

0096The anvil 5120 includes a plurality of staple forming pockets 5122 defined therein which are arranged in longitudinal rows which are registerable with the staple cavities defined in a staple cartridge. The outermost rows of forming pockets 5122 are defined in the first step 5121'. The innermost rows of forming pockets 5122 and the intermediate rows of forming pockets 5122 are defined in the second step 5121". Other possibilities are envisioned in which the intermediate rows of forming pockets 5122 are defined the first step 5121'. In any event, the anvil 5120 comprises tissue-engaging projections 5124 extending therefrom. Each projection 5124 comprises an H-shaped configuration. Such a projection 5124 can extend between adjacent forming pockets 5122 or between adjacent forming cups within a forming pocket 5122. The projection 5124 can extend around an end of a forming cup to support and guide a staple leg being formed by the forming cup, and/or it can extend along the lateral sides of a forming pocket 5122. The projection 5124 can extend along the lateral sides of a first forming pocket 5122 and a second forming pocket 5122. The lateral sides of the forming pockets 5122 can be parallel. The projections 5124 guide the staple legs within the forming cups and limit the lateral movement of the staple legs. <figref idref="f0076">FIG. 88</figref> depicts a projection 5124 on each side of a forming pocket 5122. <figref idref="f0076">FIG. 88</figref> also depicts a projection 5124 on each side of a forming cup of a forming pocket 5122. Alternatively, a projection may be positioned adjacent only some of the forming pockets 5122 of the anvil 5120 and/or only some of the forming cups of the forming pockets 5122.

0097The projections extending from an anvil may have the same height. Alternatively, the projections extending from an anvil may have different heights. Turning now to <figref idref="f0058">FIG. 69</figref>, an anvil 3520 includes a tissue-engaging surface 3321 and a longitudinal slot 3325 defined therein which is configured to receive a portion of a firing and/or cutting member. The anvil 3520 also comprises lateral sides which include a longitudinal projection, or wall, 3323 extending therefrom. The anvil 3520 includes forming pockets arranged in innermost rows 3328a, outermost rows 3328c, and rows 3328b intermediate the innermost rows 3328a and the outermost rows 3328c. The anvil 3520 comprises longitudinal rows of first projections 3551a adjacent the innermost rows 3328a, longitudinal rows of second projections 3551b adjacent the intermediate rows 3328b, and longitudinal rows of third projections 3551c adjacent the outermost rows 3228c. The first projections 3551a extend from the tissue-engaging surface 3221 a first distance and the second projections 3551b extend from the tissue-engaging surface 3221 a second distance which is different from the first distance. The third projections 3551c extend from the tissue-engaging surface 3221 a third distance which is different from the first distance and/or the second distance. The third projections 3551c can be taller than the second projections 3551b and the second projections 3551b can be taller than the first projections 3551a. Alternatively, the projections 3551a can be positioned adjacent to the intermediate rows 3328b and/or the outermost rows 3328c, the projections 3551b can be positioned adjacent to the innermost rows 3328a and/or the outermost rows 3328c, and/or the projections 3551c can be positioned adjacent to the innermost rows 3328a and/or the intermediate rows 3328b.

0098An anvil 3420 is illustrated in <figref idref="f0057">FIG. 68</figref>. The anvil 3420 comprises a distal end 3423, a proximal end, and a tissue-engaging surface 3321. The anvil 3420 further comprises a pivot 3327 about which the anvil 3420 can be rotated between an open position and a closed position. The anvil 3420 further comprises a longitudinal slot 3325 defined therein which is configured to receive a portion of a firing and/or cutting member therein. The anvil 3420 also comprises lateral sides which include a longitudinal projection, or wall, 3323 extending therefrom. The anvil 3420 includes a plurality of staple forming pockets 3322 defined therein which are arranged in longitudinal rows which are registerable with the staple cavities defined in a staple cartridge. The anvil 3420 can comprise projections extending therefrom. For example, the anvil 3420 includes pyramidal projections 3051 and/or domed-shaped projections 3151 extending therefrom. The projections 3051 and/or the projections 3151 improve the gripping force that can be applied to the tissue.

0099An anvil and the projections extending from the anvil can consist of a unitary piece of material. For example, the projections can be integrally formed with the anvil. The anvil and projections can consist of a metallic material, such as stainless steel, and can be formed during a machining and/or stamping process. In certain instances, the projections can be assembled to the anvil. For example, the projections can be adhered to the anvil. The anvil and the projections can consist of the same material or different materials. For example, the anvil can consist of a metallic material and the projections can be formed from an elastomeric material, such as rubber, a thermoplastic elastomer, and/or Santoprene. The projections can consist of a pliable material and may not traumatize the tissue compressed by the projections. Projections 3051 and/or projections 3151, can consist of an elastomeric material, such as rubber, a thermoplastic elastomer, and/or Santoprene. For example, the anvil can be formed during a machining and/or stamping process and the projections can be formed on the anvil during a molding process using a material which is more pliable than the material comprising the anvil. The projections 3051 and/or 3151, can comprise a textured anvil surface. In certain instances, the projections 3051 and/or 3151, can consist of a material which has a higher coefficient of friction than the anvil. Such embodiments can improve the gripping force between the anvil and the tissue.

0100These anvils can include a uniform array of projections extending therefrom. Alternatively, the array may not be uniform. Referring again to <figref idref="f0057">FIG. 68</figref>, projections 3051 extend from the anvil surface 3321 on a first side of the longitudinal slot 3325 and the projections 3151 extend from the anvil surface 3321 on a second side of the longitudinal slot 3325. The projections are positioned distally with respect to the forming pockets 3322. In some cases, the projections can be interspersed among the forming pockets 3322. The projections can extend from a surface 3429a defined intermediate the innermost forming pockets 3322 and the slot 3325, a surface 3429b defined intermediate the innermost forming pockets 3322 and the intermediate forming pockets 3322, a surface 3429c defined intermediate the intermediate forming pockets 3322 and the outermost forming pockets 3322, and/or a surface 3429d defined intermediate the outermost forming pockets 3322 and the lateral walls 3323.

0101<figref idref="f0083">FIG. 98</figref> depicts another anvil 5920. The anvil 5920 includes a distal end 5923, a proximal end 5926, and a tissue-engaging surface 5921. The anvil 5920 further comprises tissue-engaging members extending from the surface 5921 which are configured to prevent or limit the flow of tissue relative to the anvil 5920. For example, the anvil 5920 includes projections 5924' and projections 5924". The projections 5924" are taller than the projections 5924'. This difference in height is indicated by dimension 5925. As illustrated in <figref idref="f0083">FIG. 98</figref>, the projections 5924" are positioned distally with respect to the projections 5924'. The projections 5924" and the projections 5924' form part of a longitudinal row of projections. In other cases, the projections 5924" and the projections 5924' can be part of different longitudinal rows of projections. Although not illustrated, the projections 5924' can be positioned distally with respect to the projections 5924".

0102The anvils disclosed herein can comprise an adjunct material. An adjunct material can comprise at least one layer of material which is positioned over the tissue-engaging surface of the anvil and is implanted into the patient by staples deployed from a staple cartridge. The at least one layer of material can comprise buttress material and/or a tissue thickness compensator. The at least one layer of material can consist of Gore SeamGuard material, Synovis Peri-Strips material, and/or polyurethane. Numerous references disclose such layers: <patcit id="pcit0010" dnum="US20130161374A"><text>U.S. Patent Publication No. 2013/0161374</text></patcit>, <patcit id="pcit0011" dnum="US20120318842A"><text>U.S. Patent Publication No. 2012/0318842</text></patcit>, <patcit id="pcit0012" dnum="US20120318843A"><text>U.S. Patent Publication No. 2012/0318843</text></patcit>, <patcit id="pcit0013" dnum="US20120312860A"><text>U.S. Patent Publication No. 2012/0312860</text></patcit>, and <patcit id="pcit0014" dnum="US20120318844A"><text>U.S. Patent Publication No. 2012/0318844</text></patcit>. The layers can consist of a bioabsorbable material and/or a non-bioabsorbable material. A layer of such material can be attached to the anvil. For example, at least one adhesive can be utilized to releasably adhere the layer to the anvil, or the layer of material can be releasably attached to the anvil utilizing one or more sutures or straps. The layer can comprise projections extending therefrom which can extend into the forming pockets defined in the anvil. The projections can be arranged in an array, or pattern, which is aligned with the array, or pattern, of forming pockets in the anvil. For example, the projections can fit snugly within the forming pockets. The projections limit the lateral and/or longitudinal movement of the layer relative to the anvil.

0103The layer can comprise a solid piece of material, or it can include apertures defined therein. For example, a layer could be utilized with the anvil 3320, including apertures, slits, and/or slots, defined therein which are aligned with the projections extending from the tissue-engaging surface 3321 of the anvil 3320. The apertures can be through holes or windows extending completely through the layer. The apertures, slits, and/or slots, can be cut into a layer utilizing a bladed cutting member, formed when the layer is molded, or formed in the layer utilizing a laser cutting process. In some instances, the apertures comprise recesses defined in the layer which do not extend completely through the layer. The projections can be closely received within the apertures such that relative movement between the anvil 3320 and the layer can be prevented or at least limited. For example, an interference fit can be present between the projections and the sidewalls of the apertures.

0104The adjunct layer can consist of a woven layer and/or a non-woven layer, a film, and/or can have a textured surface, projections, and/or protrusions, extending therefrom, configured to prevent or at least limit the flow of tissue relative to the anvil. The layer can comprise a first set of regions which are engaged by and/or captured within staples ejected from a staple cartridge and a second set of regions which are not engaged by or captured within the staples. The second set of regions can be modified. For example, a layer can consist of film and the second set of regions of the film can be modified to include apertures, slits, and/or slots. The perimeter of such a layer can comprise cuts defined therein which can soften the edges of the layer. In certain instances, a pattern of cuts can be made in the layer. For example, the pattern of cuts can comprise cuts which extend at a 45 degree angle relative to one another. In some instances, the depth, width, and/or spacing of the cuts can be random. The cuts described above can make a layer of film more flexible, stretchable, and/or compliant. The cuts described above could be made to a woven or a non-woven material. The cuts described above can be made using any suitable process, such as by a mechanical blade system and/or a laser cutting system. The first set of regions of a layer may not be modified as discussed above.

0105Such a layer, consisting of a solid piece of material, can be modified to make the layer more flexible, stretchable, and/or compliant. The layer could be assembled from several pieces of material which are bonded together. For example, apertures, slits, and/or slots, can be present between the bonded pieces of material. Strips of a highly non-elastic absorbable polymer could be welded into a thinner, more flexible film to provide stretch in certain intended directions and limit stretch in others. Such strips could also be used to reinforce highly-stressed parts of the film while allowing the other parts of the film to remain soft and compliant. One way to accomplish this would be to make several thin strips comprised of a harder polymer, such as Vicryl. These strips could be approximately 0.015" to 0.030" wide, and extend the full length of a staple forming pocket line. Six strips could be arranged to correspond to the staple line lateral spread of six longitudinal staple rows. Then, a thin, continuous film layer approximately 0.003" to 0.005" thick, comprised of a soft and elastic polymer, such as Monocryl or 36/64 PGA/PCL, could be welded to the six strips. A compression molding operation could be utilized. The result would be a highly-reinforced staple line with soft sides and the ability to readily stretch laterally, but not longitudinally. The strips extending from the film could even result in traction-like holding features that would minimize tissue flow over the film in the desired direction. In certain instances, a layer comprised of a woven and/or non-woven material can be modified so as to solidify certain regions of the layer, such as the first set of regions. A flat extruded fiber could be woven into a strip and then, through the use of felting and/or another heat-based technique, the first set of regions, could be fused together to solidify them. In some instances, the entirety of the layer could be fused together.

0106Examples are disclosed herein comprising staples removably stored within a staple cartridge in an end-to-end arrangement within one or more longitudinal rows. Similarly, examples are disclosed herein comprising an anvil including staple forming pockets arranged in a corresponding end-to-end arrangement. Other staple and staple forming pocket arrangements are envisioned and are adaptable to the embodiments disclosed herein. Such arrangements may or may not comprise an end-to-end arrangement.

0107<figref idref="f0021 f0022 f0023 f0024">FIGS. 19-22</figref> depict a motor-driven surgical cutting and fastening instrument 1010 that may or may not be reused. In the illustrated embodiment, the instrument 1010 includes a housing 1012 that comprises a handle 1014 that is configured to be grasped, manipulated and actuated by the clinician. The housing 1012 is configured for operable attachment to an interchangeable shaft assembly 1200 that has a surgical end effector 1300 operably coupled thereto that is configured to perform one or more surgical tasks or procedures. It will be understood that the various unique and novel arrangements of the various forms of interchangeable shaft assemblies disclosed herein may also be effectively employed in connection with robotically-controlled surgical systems. Thus, the term "housing" may also encompass a housing or similar portion of a robotic system that houses or otherwise operably supports at least one drive system that is configured to generate and apply at least one control motion which could be used to actuate the interchangeable shaft assemblies disclosed herein and their respective equivalents. The term "frame" may refer to a portion of a handheld surgical instrument. The term "frame" may also represent a portion of a robotically controlled surgical instrument and/or a portion of the robotic system that may be used to operably control a surgical instrument. For example, the interchangeable shaft assemblies disclosed herein may be employed with various robotic systems, instruments, components and methods disclosed in U.S. Patent Application Publication No. <patcit id="pcit0015" dnum="US20120298719A"><text>US 2012/0298719</text></patcit>.

0108The housing 1012 depicted in <figref idref="f0021 f0022 f0023">FIGS. 19-21</figref> is shown in connection with an interchangeable shaft assembly 1200 that includes an end effector 1300 that comprises a surgical cutting and fastening device that is configured to operably support a surgical staple cartridge 1304 therein. The housing 1012 may be configured for use in connection with interchangeable shaft assemblies that include end effectors that are adapted to support different sizes and types of staple cartridges, have different shaft lengths, sizes, and types, etc. In addition, the housing 1012 may also be effectively employed with a variety of other interchangeable shaft assemblies including those assemblies that are configured to apply other motions and forms of energy such as, radio frequency (RF) energy, ultrasonic energy and/or motion to end effector arrangements adapted for use in connection with various surgical applications and procedures. Furthermore, the end effectors, shaft assemblies, handles, surgical instruments, and/or surgical instrument systems can utilize any suitable fastener, or fasteners, to fasten tissue. For instance, a fastener cartridge comprising a plurality of fasteners removably stored therein can be removably inserted into and/or attached to the end effector of a shaft assembly.

0109<figref idref="f0021">FIG. 19</figref> illustrates the surgical instrument 1010 with an interchangeable shaft assembly 1200 operably coupled thereto. <figref idref="f0022">FIGS. 20</figref> and <figref idref="f0023">21</figref> illustrate attachment of the interchangeable shaft assembly 1200 to the housing 1012 or handle 1014. As can be seen in <figref idref="f0023">FIG. 21</figref>, the handle 1014 comprises a pair of interconnectable handle housing segments 1016 and 1018 that may be interconnected by screws, snap features, adhesive, etc. In the illustrated arrangement, the handle housing segments 1016, 1018 cooperate to form a pistol grip portion 1019 that can be gripped and manipulated by the clinician. As will be discussed in further detail below, the handle 1014 operably supports a plurality of drive systems therein that are configured to generate and apply various control motions to corresponding portions of the interchangeable shaft assembly that is operably attached thereto.

0110Referring now to <figref idref="f0023">FIG. 21</figref>, the handle 1014 further includes a frame 1020 that operably supports a plurality of drive systems. For example, the frame 1020 operably supports a "first" or closure drive system, generally designated as 1030, which may be employed to apply closing and opening motions to the interchangeable shaft assembly 1200 that is operably attached or coupled thereto. The closure drive system 1030 includes an actuator in the form of a closure trigger 1032 that is pivotally supported by the frame 1020. More specifically, as illustrated in <figref idref="f0023">FIG. 21</figref>, the closure trigger 1032 is pivotally coupled to the housing 1014 by a pin 1033. Such arrangement enables the closure trigger 1032 to be manipulated by a clinician such that when the clinician grips the pistol grip portion 1019 of the handle 1014, the closure trigger 1032 may be easily pivoted from a starting or "unactuated" position to an "actuated" position and more particularly to a fully compressed or fully actuated position. The closure trigger 1032 may be biased into the unactuated position by spring or other biasing arrangement (not shown). The closure drive system 1030 further includes a closure linkage assembly 1034 that is pivotally coupled to the closure trigger 1032. As can be seen in <figref idref="f0023">FIG. 21</figref>, the closure linkage assembly 1034 includes a first closure link 1036 and a second closure link 1038 that are pivotally coupled to the closure trigger 1032 by a pin 1035. The second closure link 1038 is also referred to herein as an "attachment member" and include a transverse attachment pin 1037.

0111Still referring to <figref idref="f0023">FIG. 21</figref>, it can be observed that the first closure link 1036 has a locking wall or end 1039 thereon that is configured to cooperate with a closure release assembly 1060 that is pivotally coupled to the frame 1020. The closure release assembly 1060 comprises a release button assembly 1062 that has a distally protruding locking pawl 1064 formed thereon. The release button assembly 1062 may be pivoted in a counterclockwise direction by a release spring (not shown). As the clinician depresses the closure trigger 1032 from its unactuated position towards the pistol grip portion 1019 of the handle 1014, the first closure link 1036 pivots upward to a point wherein the locking pawl 1064 drops into retaining engagement with the locking wall 1039 on the first closure link 1036 thereby preventing the closure trigger 1032 from returning to the unactuated position. Thus, the closure release assembly 1060 serves to lock the closure trigger 1032 in the fully actuated position. When the clinician desires to unlock the closure trigger 1032 to permit it to be biased to the unactuated position, the clinician simply pivots the closure release button assembly 1062 such that the locking pawl 1064 is moved out of engagement with the locking wall 1039 on the first closure link 1036. When the locking pawl 1064 has been moved out of engagement with the first closure link 1036, the closure trigger 1032 may pivot back to the unactuated position. Other closure trigger locking and release arrangements may also be employed.

0112An arm 1061 extends from the closure release button 1062. A magnetic element 1063, such as a permanent magnet, is mounted to the arm 1061. When the closure release button 1062 is rotated from its first position to its second position, the magnetic element 1063 moves toward a circuit board 1100. The circuit board 1100 includes at least one sensor that is configured to detect the movement of the magnetic element 1063. A "Hall Effect" sensor (not shown) can be mounted to the bottom surface of the circuit board 1100. The Hall Effect sensor is configured to detect changes in a magnetic field surrounding the Hall Effect sensor caused by the movement of the magnetic element 1063. The Hall Effect sensor is in signal communication with a microcontroller, which determines whether the closure release button 1062 is in its first position, which is associated with the unactuated position of the closure trigger 1032 and the open configuration of the end effector, its second position, which is associated with the actuated position of the closure trigger 1032 and the closed configuration of the end effector, and/or any position between the first position and the second position.

0113The handle 1014 and the frame 1020 operably support another drive system referred to herein as a firing drive system 1080 that is configured to apply firing motions to corresponding portions of the interchangeable shaft assembly attached thereto. The firing drive system may 1080 also be referred to herein as a "second drive system". The firing drive system 1080 employs an electric motor 1082 that is located in the pistol grip portion 1019 of the handle 1014. The motor 1082 may be a DC brushed driving motor having a maximum rotation of, approximately, 25,000 RPM. Alternatively, the motor may include a brushless motor, a cordless motor, a synchronous motor, a stepper motor, or any other suitable electric motor. The motor 1082 may be powered by a power source 1090 that comprises a removable power pack 1092. As can be seen in <figref idref="f0023">FIG. 21</figref>, the power pack 1092 comprises a proximal housing portion 1094 that is configured for attachment to a distal housing portion 1096. The proximal housing portion 1094 and the distal housing portion 1096 are configured to operably support a plurality of batteries 1098 therein. Batteries 1098 may each comprise, a Lithium Ion ("LI") or other suitable battery. The distal housing portion 1096 is configured for removable operable attachment to the circuit board assembly 1100 which is also operably coupled to the motor 1082. A number of batteries 1098 may be connected in series may be used as the power source for the surgical instrument 1010. In addition, the power source 1090 may be replaceable and/or rechargeable.

0114The electric motor 1082 includes a rotatable shaft (not shown) that operably interfaces with a gear reducer assembly 1084 that is mounted in meshing engagement with a with a set, or rack, of drive teeth 1122 on a longitudinally-movable drive member 1120. A voltage polarity provided by the power source 1090 operates the electric motor 1082 in a clockwise direction wherein the voltage polarity applied to the electric motor by the battery can be reversed in order to operate the electric motor 1082 in a counter-clockwise direction. When the electric motor 1082 is rotated in one direction, the drive member 1120 will be axially driven in the distal direction "DD". When the motor 82 is driven in the opposite rotary direction, the drive member 1120 will be axially driven in a proximal direction "PD". The handle 1014 includes a switch which is configured to reverse the polarity applied to the electric motor 1082 by the power source 1090. The handle 1014 can also include a sensor that is configured to detect the position of the drive member 1120 and/or the direction in which the drive member 1120 is being moved.

0115Actuation of the motor 1082 can be controlled by a firing trigger 1130 that is pivotally supported on the handle 1014. The firing trigger 1130 is pivoted between an unactuated position and an actuated position. The firing trigger 1130 may be biased into the unactuated position by a spring 1132 or other biasing arrangement such that when the clinician releases the firing trigger 1130, it may be pivoted or otherwise returned to the unactuated position by the spring 1132 or biasing arrangement. The firing trigger 1130 is positioned "outboard" of the closure trigger 132. A firing trigger safety button 1134 is pivotally mounted to the closure trigger 1032 by pin 1035. The safety button 1134 is positioned between the firing trigger 1130 and the closure trigger 1032 and has a pivot arm 1136 protruding therefrom. See <figref idref="f0023">FIG. 21</figref>. When the closure trigger 1032 is in the unactuated position, the safety button 1134 is contained in the handle 1014 where the clinician cannot readily access it and move it between a safety position preventing actuation of the firing trigger 1130 and a firing position wherein the firing trigger 1130 may be fired. As the clinician depresses the closure trigger 1032, the safety button 1134 and the firing trigger 1130 pivot down wherein they can then be manipulated by the clinician.

0116The longitudinally movable drive member 1120 has a rack of teeth 1122 formed thereon for meshing engagement with a corresponding drive gear 1086 of the gear reducer assembly 1084. It also includes a manually-actuatable "bailout" assembly 1140 that is configured to enable the clinician to manually retract the longitudinally movable drive member 1120 should the motor 1082 become disabled. The bailout assembly 1140 includes a lever or bailout handle assembly 1142 that is configured to be manually pivoted into ratcheting engagement with teeth 1124 also provided in the drive member 1120. Thus, the clinician can manually retract the drive member 1120 by using the bailout handle assembly 1142 to ratchet the drive member 1120 in the proximal direction "PD". <patcit id="pcit0016" dnum="US8608045B"><text>U.S. Patent No. 8,608,045</text></patcit>, discloses bailout arrangements and other components, arrangements and systems that may also be employed with the various instruments disclosed herein.

0117Turning now to <figref idref="f0022">FIGS. 20</figref> and <figref idref="f0024">22</figref>, the interchangeable shaft assembly 1200 includes a surgical end effector 1300 that comprises an elongate channel 1302 that is configured to operably support a staple cartridge 1304 therein. The end effector 1300 further includes an anvil 1306 that is pivotally supported relative to the elongate channel 1302. The interchangeable shaft assembly 1200 further includes an articulation joint 1270 and an articulation lock which are configured to releasably hold the end effector 1300 in a desired position relative to a shaft axis SA-SA. Details regarding the construction and operation of the end effector 1300, the articulation joint 1270 and the articulation lock are set forth in <patcit id="pcit0017" dnum="US20140263541A"><text>U.S. Patent Publication No. 2014/0263541</text></patcit>. As can be seen in <figref idref="f0024">FIG. 22</figref>, the interchangeable shaft assembly 1200 further includes a proximal housing or nozzle 1201 comprised of nozzle portions 1202 and 1203. The interchangeable shaft assembly 1200 further includes a closure tube 1260 which can be utilized to close and/or open the anvil 1306 of the end effector 1300. The shaft assembly 1200 includes a spine 1210 that is configured to, one, slidably support a firing member therein and, two, slidably support the closure tube 1260 which extends around the spine 210. The spine 210 can also be configured to slidably support a proximal articulation driver. The articulation driver has a distal end that is configured to operably engage the articulation lock. The articulation lock interfaces with an articulation frame that is adapted to operably engage a drive pin on the end effector frame. As indicated above, further details regarding the operation of the articulation lock and the articulation frame may be found in <patcit id="pcit0018" dnum="US803086A" dnum-type="L"><text>U.S. Patent Application Serial No. 13/803,086</text></patcit>. The spine 1210 can comprise a proximal end 1211 which is rotatably supported in a chassis 1240. In one arrangement, the proximal end 1211 of the spine 1210 has a thread 1214 formed thereon for threaded attachment to a spine bearing 1216 configured to be supported within the chassis 1240. See <figref idref="f0024">FIG. 22</figref>. Such an arrangement facilitates rotatable attachment of the spine 1210 to the chassis 1240 such that the spine 1210 may be selectively rotated about a shaft axis SA relative to the chassis 1240.

0118Referring primarily to <figref idref="f0024">FIG. 22</figref>, the interchangeable shaft assembly 1200 includes a closure shuttle 1250 that is slidably supported within the chassis 1240 such that it may be axially moved relative thereto. The closure shuttle 1250 includes a pair of proximally-protruding hooks 1252 that are configured for attachment to the attachment pin 1037 (<figref idref="f0022">FIGS. 20</figref> and <figref idref="f0023">21</figref>) that is attached to the second closure link 1038 as will be discussed in further detail below. A proximal end 1261 of the closure tube 1260 is coupled to the closure shuttle 1250 for relative rotation thereto. For example, a U shaped connector 1263 is inserted into an annular slot 1262 in the proximal end 1261 of the closure tube 1260 and is retained within vertical slots 1253 in the closure shuttle 1250. Such an arrangement serves to attach the closure tube 1260 to the closure shuttle 1250 for axial travel therewith while enabling the closure tube 1260 to rotate relative to the closure shuttle 1250 about the shaft axis SA. A closure spring 1268 is journaled on the closure tube 1260 and serves to bias the closure tube 1260 in the proximal direction "PD" which can serve to pivot the closure trigger into the unactuated position when the shaft assembly is operably coupled to the handle 1014.

0119The interchangeable shaft assembly 1200 further includes an articulation joint 1270. Other interchangeable shaft assemblies, however, may not be capable of articulation. As can be seen in <figref idref="f0024">FIG. 22</figref>, the articulation joint 1270 includes a double pivot closure sleeve assembly 1271. The double pivot closure sleeve assembly 1271 includes an end effector closure sleeve assembly 1272 having upper and lower distally projecting tangs 1273, 1274. An end effector closure sleeve assembly 1272 includes a horseshoe aperture 1275 and a tab 1276 for engaging an opening tab on the anvil 1306 in the various manners described in <patcit id="pcit0019" dnum="US20140263541A"><text>U.S. Patent Publication No. 2014/0263541</text></patcit>. As described in further detail therein, the horseshoe aperture 1275 and tab 1276 engage a tab on the anvil when the anvil 1306 is opened. An upper double pivot link 1277 includes upwardly projecting distal and proximal pivot pins that engage respectively an upper distal pin hole in the upper proximally projecting tang 1273 and an upper proximal pin hole in an upper distally projecting tang 1264 on the closure tube 1260. A lower double pivot link 1278 includes upwardly projecting distal and proximal pivot pins that engage respectively a lower distal pin hole in the lower proximally projecting tang 1274 and a lower proximal pin hole in the lower distally projecting tang 1265. See also <figref idref="f0024">FIG. 22</figref>.

0120In use, the closure tube 1260 is translated distally (direction "DD") to close the anvil 1306, in response to the actuation of the closure trigger 1032. The anvil 1306 is closed by distally translating the closure tube 1260 and thus the shaft closure sleeve assembly 1272, causing it to strike a proximal surface on the anvil 1360 in the manner described in the aforementioned referenced <patcit id="pcit0020" dnum="US803086A" dnum-type="L"><text>U.S. Patent Application Serial No. 13/803,086</text></patcit>. As was also described in detail in that reference, the anvil 1306 is opened by proximally translating the closure tube 1260 and the shaft closure sleeve assembly 1272, causing tab 1276 and the horseshoe aperture 1275 to contact and push against the anvil tab to lift the anvil 1306. In the anvil-open position, the shaft closure tube 1260 is moved to its proximal position.

0121Also, the interchangeable shaft assembly 1200 further includes a firing member that is supported for axial travel within the shaft spine 1210. The firing member includes an intermediate firing shaft portion 1222 that is configured for attachment to a distal cutting portion or knife bar. The intermediate firing shaft portion 1222 may include a longitudinal slot in the distal end thereof which is configured to receive a tab on the proximal end of the distal knife bar. The longitudinal slot and the proximal end can be sized and configured to permit relative movement therebetween and can comprise a slip joint. The slip joint can permit the intermediate firing shaft portion 1222 of the firing drive to be moved to articulate the end effector 1300 without moving, or at least substantially moving, the knife bar. Once the end effector 1300 has been suitably oriented, the intermediate firing shaft portion 1222 can be advanced distally until a proximal sidewall of the longitudinal slot comes into contact with the tab in order to advance the knife bar and fire the staple cartridge positioned within the channel 1302. Further description of the operation of the firing member may be found in <patcit id="pcit0021" dnum="US803086A" dnum-type="L"><text>U.S. Patent Application Serial No. 13/803,086</text></patcit>.

0122As can be seen in <figref idref="f0024">FIG. 22</figref>, the shaft assembly 1200 further includes a switch drum 1500 that is rotatably received on the closure tube 1260. The switch drum 1500 comprises a hollow shaft segment 1502 that has a shaft boss formed thereon for receive an outwardly protruding actuation pin therein. The actuation pin extends through a longitudinal slot provided in the lock sleeve to facilitate axial movement of the lock sleeve when it is engaged with the articulation driver. A rotary torsion spring 1420 is configured to engage the boss on the switch drum 1500 and a portion of the nozzle housing 1203 to apply a biasing force to the switch drum 1500. The switch drum 1500 further comprises at least partially circumferential openings 1506 defined therein which are configured to receive circumferential mounts extending from the nozzle halves 1202, 1203 and permit relative rotation, but not translation, between the switch drum 1500 and the proximal nozzle 1201. The mounts also extend through openings 1266 in the closure tube 1260 to be seated in recesses in the shaft spine 1210. However, rotation of the nozzle 1201 to a point where the mounts reach the end of their respective slots 1506 in the switch drum 1500 will result in rotation of the switch drum 1500 about the shaft axis SA. Rotation of the switch drum 1500 will ultimately result in the rotation of the actuation pin and the lock sleeve between its engaged and disengaged positions. Thus, in essence, the nozzle 1201 maybe employed to operably engage and disengage the articulation drive system with the firing drive system in the various manners described in further detail in <patcit id="pcit0022" dnum="US20140263541A"><text>U.S. Patent Publication No. 2014/0263541</text></patcit> and <patcit id="pcit0023" dnum="US20150272575A"><text>U.S. Patent Publication No. 2015/0272575</text></patcit>.

0123As also illustrated in <figref idref="f0024">FIG. 22</figref>, the shaft assembly 1200 comprises a slip ring assembly 1600 which is configured to conduct electrical power to and/or from the end effector 1300 and/or communicate signals to and/or from the end effector 1300. The slip ring assembly 1600 comprises a proximal connector flange 1604 that is mounted to a chassis flange 1242 that extends from the chassis 1240 and a distal connector flange that is positioned within a slot defined in the shaft housings. The proximal connector flange 1604 comprises a first face and the distal connector flange comprises a second face which is positioned adjacent to and movable relative to the first face. The distal connector flange can rotate relative to the proximal connector flange 1604 about the shaft axis SA. The proximal connector flange 1604 comprises a plurality of concentric, or at least substantially concentric, conductors defined in the first face thereof. A connector can be mounted on the proximal side of the connector flange and may have a plurality of contacts wherein each contact corresponds to and is in electrical contact with one of the conductors. Such an arrangement permits relative rotation between the proximal connector flange 1604 and the distal connector flange while maintaining electrical contact therebetween. The proximal connector flange 1604 can include an electrical connector 1606 which can place the conductors in signal communication with a shaft circuit board 1610 mounted to the shaft chassis 1240. For example, a wiring harness comprising a plurality of conductors can extend between the electrical connector 1606 and the shaft circuit board 1610. The electrical connector 1606 may extend proximally through a connector opening 1243 defined in the chassis mounting flange 1242. See <figref idref="f0024">FIG. 22</figref>. Further details regarding slip ring assembly 1600 maybe found in <patcit id="pcit0024" dnum="US20140263541A"><text>U.S. Patent Publication No. 2014/0263541</text></patcit>.

0124As discussed above, the shaft assembly 1200 includes a proximal portion which is fixably mounted to the handle 1014 and a distal portion which is rotatable about a longitudinal axis. The rotatable distal shaft portion can be rotated relative to the proximal portion about the slip ring assembly 1600. The distal connector flange of the slip ring assembly 1600 can be positioned within the rotatable distal shaft portion. Moreover, the switch drum 1500 can also be positioned within the rotatable distal shaft portion. When the rotatable distal shaft portion is rotated, the distal connector flange and the switch drum 1500 can be rotated synchronously with one another. In addition, the switch drum 1500 can be rotated between a first position and a second position relative to the distal connector flange. When the switch drum 1500 is in its first position, the articulation drive system may be operably disengaged from the firing drive system and, thus, the operation of the firing drive system may not articulate the end effector 1300 of the shaft assembly 1200. When the switch drum 1500 is in its second position, the articulation drive system may be operably engaged with the firing drive system and, thus, the operation of the firing drive system may articulate the end effector 1300 ofthe shaft assembly 1200. When the switch drum 1500 is moved between its first position and its second position, the switch drum 1500 is moved relative to distal connector flange. The shaft assembly 1200 comprises at least one sensor configured to detect the position of the switch drum 1500.

0125Referring again to <figref idref="f0024">FIG. 22</figref>, the chassis 1240 includes at least one, and preferably two, tapered attachment portions 1244 formed thereon that are adapted to be received within corresponding dovetail slots 1702 formed within a distal attachment flange portion 1700 of the frame 1020. See <figref idref="f0023">FIG. 21</figref>. Each dovetail slot 1702 may be tapered or, stated another way, be somewhat V-shaped to seatingly receive the attachment portions 1244 therein. As can be further seen in <figref idref="f0024">FIG. 22</figref>, a shaft attachment lug 1226 is formed on the proximal end of the intermediate firing shaft 1222. As will be discussed in further detail below, when the interchangeable shaft assembly 1200 is coupled to the handle 1014, the shaft attachment lug 1226 is received in a firing shaft attachment cradle 1126 formed in the distal end 1125 of the longitudinal drive member 1120. See <figref idref="f0023">FIG. 21</figref>.

0126Various shaft assembly embodiments employ a latch system 1710 for removably coupling the shaft assembly 1200 to the housing 1012 and more specifically to the frame 1020. As can be seen in <figref idref="f0024">FIG. 22</figref>, the latch system 1710 includes a lock member or lock yoke 1712 that is movably coupled to the chassis 1240. In the illustrated embodiment, the lock yoke 1712 has a U-shape with two spaced downwardly extending legs 1714. The legs 1714 each have a pivot lug 1715 formed thereon that are adapted to be received in corresponding holes 1245 formed in the chassis 1240. Such arrangement facilitates pivotal attachment of the lock yoke 1712 to the chassis 1240. The lock yoke 1712 includes two proximally protruding lock lugs 1716 that are configured for releasable engagement with corresponding lock detents or grooves 1704 in the distal attachment flange 1700 of the frame 1020. See <figref idref="f0023">FIG. 21</figref>. The lock yoke 1712 is biased in the proximal direction by spring or biasing member (not shown). Actuation of the lock yoke 1712 may be accomplished by a latch button 1722 that is slidably mounted on a latch actuator assembly 1720 that is mounted to the chassis 1240. The latch button 1722 may be biased in a proximal direction relative to the lock yoke 1712. As will be discussed in further detail below, the lock yoke 1712 may be moved to an unlocked position by biasing the latch button the in distal direction which also causes the lock yoke 1712 to pivot out of retaining engagement with the distal attachment flange 1700 of the frame 1020. When the lock yoke 1712 is in "retaining engagement" with the distal attachment flange 1700 of the frame 1020, the lock lugs 1716 are retainingly seated within the corresponding lock detents or grooves 1704 in the distal attachment flange 1700.

0127When employing an interchangeable shaft assembly that includes an end effector of the type described herein that is adapted to cut and fasten tissue, as well as other types of end effectors, it may be desirable to prevent inadvertent detachment of the interchangeable shaft assembly from the housing during actuation of the end effector. For example, in use the clinician may actuate the closure trigger 32 to grasp and manipulate the target tissue into a desired position. Once the target tissue is positioned within the end effector 1300 in a desired orientation, the clinician may then fully actuate the closure trigger 1032 to close the anvil 1306 and clamp the target tissue in position for cutting and stapling. In that instance, the first drive system 1030 has been fully actuated. After the target tissue has been clamped in the end effector 1300, it may be desirable to prevent the inadvertent detachment of the shaft assembly 1200 from the housing 1012. One form of the latch system 1710 is configured to prevent such inadvertent detachment.

0128As can be most particularly seen in <figref idref="f0024">FIG. 22</figref>, the lock yoke 1712 includes at least one and preferably two lock hooks 1718 that are adapted to contact corresponding lock lug portions 1256 that are formed on the closure shuttle 1250. When the closure shuttle 1250 is in an unactuated position (i.e., the first drive system 1030 is unactuated and the anvil 1306 is open), the lock yoke 1712 may be pivoted in a distal direction to unlock the interchangeable shaft assembly 1200 from the housing 1012. When in that position, the lock hooks 1718 do not contact the lock lug portions 1256 on the closure shuttle 1250. However, when the closure shuttle 1250 is moved to an actuated position (i.e., the first drive system 1030 is actuated and the anvil 1306 is in the closed position), the lock yoke 1712 is prevented from being pivoted to an unlocked position. Stated another way, if the clinician were to attempt to pivot the lock yoke 1712 to an unlocked position or, the lock yoke 1712 was in advertently bumped or contacted in a manner that might otherwise cause it to pivot distally, the lock hooks 1718 on the lock yoke 1712 will contact the lock lugs 1256 on the closure shuttle 1250 and prevent movement of the lock yoke 1712 to an unlocked position.

0129Attachment of the interchangeable shaft assembly 1200 to the handle 1014 will now be described. To commence the coupling process, the clinician may position the chassis 1240 of the interchangeable shaft assembly 1200 above or adjacent to the distal attachment flange 1700 of the frame 1020 such that the tapered attachment portions 1244 formed on the chassis 1240 are aligned with the dovetail slots 1702 in the frame 1020. The clinician may then move the shaft assembly 1200 along an installation axis that is perpendicular to the shaft axis SA to seat the attachment portions 1244 in "operable engagement" with the corresponding dovetail receiving slots 1702. In doing so, the shaft attachment lug 1226 on the intermediate firing shaft 1222 will also be seated in the cradle 1126 in the longitudinally movable drive member 1120 and the portions of pin 1037 on the second closure link 1038 will be seated in the corresponding hooks 1252 in the closure yoke 1250. As used herein, the term "operable engagement" in the context of two components means that the two components are sufficiently engaged with each other so that upon application of an actuation motion thereto, the components may carry out their intended action, function and/or procedure.

0130At least five systems of the interchangeable shaft assembly 1200 can be operably coupled with at least five corresponding systems of the handle 1014. A first system comprises a frame system which couples and/or aligns the frame or spine of the shaft assembly 1200 with the frame 1020 of the handle 1014. Another system comprises a closure drive system 1030 which can operably connect the closure trigger 1032 of the handle 1014 and the closure tube 1260 and the anvil 1306 of the shaft assembly 1200. As outlined above, the closure tube attachment yoke 1250 ofthe shaft assembly 1200 can be engaged with the pin 1037 on the second closure link 1038. Another system comprises the firing drive system 1080 which can operably connect the firing trigger 1130 ofthe handle 1014 with the intermediate firing shaft 1222 of the shaft assembly 1200. As outlined above, the shaft attachment lug 1226 can be operably connected with the cradle 1126 of the longitudinal drive member 1120. Another system comprises an electrical system which can signal to a controller in the handle 1014, such as microcontroller, that a shaft assembly, such as shaft assembly 1200, has been operably engaged with the handle 1014 and/or, two, conduct power and/or communication signals between the shaft assembly 1200 and the handle 1014. For instance, the shaft assembly 1200 includes an electrical connector 1810 that is operably mounted to the shaft circuit board 1610. The electrical connector 1810 is configured for mating engagement with a corresponding electrical connector 1800 on the handle control board 1100. Further details regaining the circuitry and control systems may be found in <patcit id="pcit0025" dnum="US20140263541A"><text>U.S. Patent Publication No. 2014/0263541</text></patcit>, and <patcit id="pcit0026" dnum="US20150272575A"><text>U.S. Patent Publication No. 2015/0272575</text></patcit>. The fifth system may consist of the latching system for releasably locking the shaft assembly 1200 to the handle 1014.

0131Surgical staplers have been used in the prior art to simultaneously make a longitudinal incision in tissue and apply lines of staples on opposing sides of the incision. Such instruments commonly include a pair of cooperating jaw members that, if the instrument is intended for endoscopic or laparoscopic applications, are capable of passing through a cannula passageway. One of the jaw members receives a staple cartridge having at least two laterally spaced rows of staples. The other jaw member defines an anvil having staple-forming pockets aligned with the rows of staples in the cartridge. The instrument includes a plurality of reciprocating wedges which, when driven distally, pass through openings in the staple cartridge and engage drivers supporting the staples to effect the firing of the staples toward the anvil.

0132The simultaneous severing of tissue while forming rows of staples on each side of the cut reduces bleeding and simplifies the surgical procedure. Increasingly, endoscopic and laparoscopic procedures are preferred over open procedures due to their reduced post-operative recovery times and other advantages. Endoscopic stapling and severing instruments use a long slender jaw member that tends to deflect upwardly when clamped onto thick tissues. On thick tissue, this upward deflection of the free (distal) end of the jaw can cause differences in height of the formed staples as the distal gap between the anvil and cartridge is larger than the proximal gap. To ensure more uniform proximal to distal staple formation, the anvil is frequently cambered or bent inwardly toward the staple cartridge. This camber is better for thick tissue and can cause tighter staple forms at the distal end when used on thin tissue. To overcome this tight distal closure, pins or bumps have been added to the clamping surface of the cartridge adjacent to the distal end of the cartridge. The closure of the anvil onto the pin ensures a minimum gap at the distal end. However, surgeons were concerned about the pins or bumps causing tissue trauma.

0133Various arrangements have been developed to address such challenges. One arrangement, comprises an "E-beam" cutting head or firing bar that is configured to affirmatively space the anvil from the elongate channel that supports the staple cartridge. Such E-beam cutting head and firing bar arrangements are disclosed in, <patcit id="pcit0027" dnum="US6978921B"><text>U.S. Patent No. 6,978,921</text></patcit>, entitled SURGICAL STAPLING INSTRUMENT INCORPORATING AN E-BEAM FIRING MECHANISM.

0134For example, as illustrated in <figref idref="f0001">FIGS. 2</figref> and <figref idref="f0002">3</figref> herein the tissue-cutting head comprises an E-beam 50 which can translate within the end effector 16. As described above, the E-beam 50 comprises a vertical portion 52 which can pass through a narrow longitudinal anvil slot 58 extending through a tissue-contacting surface 60 in the anvil 20, a narrow vertical slot 62 in the staple cartridge 42, and a narrow longitudinal channel slot 64 in the elongate staple channel 40 when the E-beam 50 is advanced distally. The anvil slot 58 extends upwardly into the anvil 20 and comprises an end which opens into a laterally-widened longitudinal channel 66 sized and configured to receive an upper pin 54 that extends laterally from the vertical portion 52. Similarly, the channel slot 64 extends downwardly into the channel 40 and comprises an end which opens into a laterally-widened longitudinal channel 68 sized and configured to receive one or more lower feet 70 extending laterally from the vertical portion 52. The E-beam 50 further comprises one or more middle pins 72 which can extend laterally from the vertical portion 52 and are configured to slide along a top surface of a bottom tray 74 of the staple cartridge 42. The middle pins 72 are configured to seat the staple cartridge 42, or assure that the staple cartridge 42 remains seated, in the channel 40. A longitudinal firing recess 75 formed in the staple cartridge 42 above the bottom tray 74 is sized to allow the middle pins 72 to translate through the staple cartridge 42.

0135Various elongate channel arrangements include an elongate or longitudinal slot that extends between a starting position of the E-beam cutting head in a proximal portion of the elongate channel and an ending position adjacent the distal end of the elongate channel. The vertical portion of the E-beam cutting head extends through that longitudinal slot and the lower foot portion of the E-beam rides along the bottom surface of the elongate channel. The foot portion may help affirmatively space the anvil relative to the elongate channel and can also serve as convenient means for the clinician to ascertain the position of the cutting head in the elongate channel. By observing the position of the cutting head foot as the cutting head is advanced distally through the cartridge, the clinician will know exactly where the cutting head is located within the cartridge. While providing an effective means for spacing the anvil and for monitoring the location of the cutting head, such arrangement does employ a longitudinal slot in the elongate channel which may reduce the channel stiffness as well as the channel's resistance to twisting and spreading.

0136To avoid such spreading of the elongate channel, it may be desirable to eliminate the longitudinal slot to increase the resistance to twisting and spreading when stapling thick tissue. However, such arrangement may eliminate the ability of the surgeon to see how far the stapling has progressed by observing the position of the knife foot. <figref idref="f0030">FIG. 32</figref> illustrates an elongate channel 6022 that may be similar to various elongate channels disclosed herein including, elongate channels 22 and 302 except for the following differences. Elongate channel 6022 may be molded, and/or machined and/or otherwise formed from a suitable polymer material and include a substantially solid bottom surface portion 6024. The elongate channel 6022 is configured to operably support a surgical staple cartridge (not shown) therein. The elongate channel 6022 may include an elongate internal slot 6026 that is defined by two inwardly extending ledge portions 6028. The inwardly extending ledge portions 6028 also define an elongate internal passageway 6030 between the ledge portions 6028 and the solid bottom portion 6024. While the elongate internal slot 6026 extends for most of the length of the elongate channel 6022, it does not extend through the bottom surface 6024 of the elongate channel 6022. The internal passageway 6030 is sized to slidably accommodate the foot or feet that are formed on or otherwise attached to the cutting head.

0137<figref idref="f0036">FIG. 42</figref> illustrates, an E-beam cutting head 6050 that may be used in connection with the elongate channel 6022. However, as will become apparent, the elongate channel 6022 may also be used in connection with a variety of different cutting head arrangements that employ a single foot or a plurality of feet on the bottom of the cutting head. Referring to <figref idref="f0036">FIG. 42</figref>, the cutting head 6050 includes a vertical portion 6052 that terminates with two laterally extending lower feet 6070. The vertical portion 6052 is configured to pass through the elongate slot 6026 such that the lower feet 6070 are received under the corresponding ledge portions 6028.

0138Referring again to <figref idref="f0030">FIG. 32</figref>, the elongate channel 6022 may further include a proximal channel opening 6040 that is provided in the proximal end of the bottom portion 6024 of the elongate channel 6022. The proximal channel opening 6040 may afford the clinician with a view of at least one of the feet 6070 or other portion(s) of the cutting head 6050 when the cutting head 6050 is in a starting or unfired position. This "starting position" may also correspond to a position that the cutting head 6050 is in when cutting head 6050 is in a locked out position as will be discussed in further detail below. Similarly a distal channel opening 6042 is provided in the distal end of the bottom portion 6024 which affords the clinician with a view of at least one of the feet 6070 or other portion(s) of the cutting head 6050 when the cutting head 6050 is in its "fully-fired" or "ending position". Such arrangement affords the clinician with a method for ascertaining whether the cutting head is in its starting or ending position while providing a relatively stiffer elongate channel when compared with other channels that have a longitudinal slot that extends longitudinally through the bottom of the elongate channel. The proximal channel opening 6040 and the distal channel opening 6042 may be shaped in the manners illustrated in <figref idref="f0030">FIG. 32</figref> to facilitate easy installation of the cutting head 6050 into the elongate channel 6022 (through proximal channel opening 6040) and removal of the cutting head 6050 from the elongate channel 6022 (through the distal channel opening 6042) for example. Thus, the elongate channel 6022 has a closed bottom with openings 6040, 6042 corresponding to the beginning and end, respectively of the cutting head firing stroke. Such arrangement allows for the visibility of the beginning and ending of firing as well as permitting the downward movement of the cutting head to a locked position as will be discussed in further detail below.

0139The elongate channel 6022 may be effectively employed with a cutting head assembly that is manually advanced or one that is advanced by means of a motor-powered firing system. For example, the surgical instrument 10 described above includes a cutting head 50 that is manually advanced by actuating the trigger 32. The cutting head 50 may be advanced from its starting to ending position by actuating the firing trigger 32 three times. Thus, activating the trigger 32 one time may move the cutting head distally in the elongate channel one third of the distance between the starting position and the ending position ("first firing position"). Activating the trigger a second time may result in the cutting head 50 travelling two-thirds of the way between the starting and end position ("second firing position") and activating the trigger 32 a third time may result in the advancement of the cutting head 50 from the second firing position to the ending position. Thus, when the cutting head 6050 is viewable through the distal channel opening 6042, the clinician will know that the cutting head 6050 has been fully fired. Such elongate channel 6022 may also be employed in connection with the powered surgical instrument 1010 (<figref idref="f0021 f0022 f0023 f0024">FIGS. 19-22</figref>).

0140<figref idref="f0031 f0032">FIGS. 33-35</figref> illustrate another elongate channel arrangement 6122 that is similar to the elongate channel 6022 except for the noted differences. Those portions of the elongate channel arrangement 6122 that are identical to portions of elongate channel arrangement 6022 will share the same element numbers. In particular, as can be seen in <figref idref="f0031">FIG. 33</figref>, a series of spaced indicator openings 6144 are provided in the bottom portion 6124. The indicator openings 6144 may vary in number, size and spacing, but in at least one arrangement, the indicator openings 6144 have the same size and are equally spaced in a line such that they open into the elongate internal passageway 6030. As can be seen in those Figures, the indicator openings 6144 are round in shape. As can also be seen in <figref idref="f0031">FIG. 33</figref>, a light source 6160 maybe mounted within a proximal end of the elongate channel 6122 such that the light source 6160 projects light into the internal passageway 6030 (represented by the broken line "L" in <figref idref="f0031">FIGS. 33</figref> and <figref idref="f0032">34</figref>). The light source 6160 may comprise, one or more light emitting diodes ("LED's) or other light source arrangement that may receive power through a conductor 6164 that is coupled to the handle of the surgical instrument or robotic system, etc. To which the elongate channel 6122 is operably attached. When the light source 6160 is powered, the light will be projected into the internal passageway 6030. When the cutting head 6050 is in the starting position, the cutting head 6050 may block any light "L" from being visible through any of the indicator openings 6144. Thus, when no light "L" is visible through any of the indicator openings 6144, the clinician will know that the cutting head 6050 is in the starting position. As the cutting head 6050 is advanced distally past indicator openings 6144, the light "L" will strike the cutting head 6050-and be visible at least through the unobstructed indicator opening 6144 that is immediately proximal to the cutting head 6050 as shown in <figref idref="f0032">FIG. 34</figref>. Thus, such arrangement enables the clinician to monitor the progress of the cutting head 6050 as it moves distally in the elongate channel 6122 from its starting position to its ending position. Such elongate channel arrangement is also more stiff and rigid than those elongate channel arrangements that have an elongate slot that extends completely through most of the bottom surface of the elongate channel. In one arrangement the clinician can determine the position of the cutting head because there will be no light shining through the indicator opening where the cutting head is located. All of the other indicator openings will have light shining through them. Thus in one arrangement, the "black" or unlit indicator opening is where the cutting head is located. In other embodiments, the light source may be omitted. The clinician can still monitor the position of the cutting head 6050 in the elongate channel 6122 by viewing the location of the feet 6070 through the indicator openings 6144.

0141<figref idref="f0033">FIG. 36</figref> illustrates another elongate channel arrangement 6222 that is similar to the elongate channel 6122 except for the noted differences. Those portions of the elongate channel arrangement 6222 that are identical to portions of elongate channel arrangement 6122 will share the same element numbers. As can be seen in that Figure, a series of spaced indicator openings 6144 are provided through the bottom surface 6224. In the illustrated arrangement, the indicator openings 6144 have the same size and shape but are provided through the bottom surface 6224 at different spacing intervals. For example, the proximal-most indicator opening 6144P maybe spaced from the proximal opening 6040 a first spacing distance "FSD" that enables, at least one of the feet 6070 or other portion of the cutting head 6050 to be viewed therethrough when the cutting head 6050 is in the starting position. Likewise, the distal-most indicator opening 6144D maybe spaced from the adjacent indicator opening 6144 a second spacing distance "SSD" that is different from the first spacing distance FSD. As can be seen in <figref idref="f0033">FIG. 36</figref> the SSD is greater than the FSD. The distal-most indicator opening 6144D may correspond to the position of the cutting head 6050 in its ending position. Thus, the elongate channel arrangement 6222 illustrates variable spaced indicator openings wherein the number of openings decrease as you move proximal to distal.

0142<figref idref="f0033">FIG. 37</figref> illustrates another elongate channel arrangement 6322 that is similar to the elongate channel 6122 except for the noted differences. Those portions of the elongate channel arrangement 6322 that are identical to portions of elongate channel arrangement 6122 will share the same element numbers. As can be seen in that Figure, the elongate channel arrangement 6322 includes a series of elongate discrete indicator openings 6144'. In the illustrated arrangement, the indicator openings 6144' have the same size and shape and are arranged at equally spaced intervals.

0143<figref idref="f0034">FIG. 38</figref> illustrates another elongate channel arrangement 6422 that is similar to the elongate channel 6222 except for the noted differences. Those portions of the elongate channel arrangement 6422 that are identical to portions of elongate channel arrangement 6222 will share the same element numbers. As can be seen in that Figure, only two spaced "discrete" indicator openings 6144" are provided through the bottom surface 6424. In the illustrated arrangement, the indicator openings 6144" have the same size and shape but are provided through the bottom surface 6424 at different spacing intervals. For example, the proximal-most indicator opening 6144P" maybe spaced from the proximal opening 6040 a first spacing distance "FSD" and the distal-most indicator opening 6144D" maybe spaced from the proximal-most indicator opening 6144" a second spacing distance "SSD" that is different from the first spacing distance FSD. In at least one arrangement when the elongate channel 6422 is employed with a cutting head assembly that is manually advanced by actuating the firing trigger, at least one foot or other portion of the cutting head assembly is viewable through the proximal indicator opening 6144P" when the cutting head assembly is being advanced through the "first stroke" or first actuation of the firing trigger. Likewise, at least one foot or other portion of the cutting head assembly is viewable through the distal most indication opening 6144D" during the second stroke or second actuation sequence of the firing trigger. Thus, the elongate channel 6422 includes elongate slot-shaped indicator openings as well as circular shaped indicator openings that provide more closure/less openings as you move proximal to distal.

0144<figref idref="f0034">FIG. 39</figref> illustrates another elongate channel arrangement 6522 that is similar to the elongate channel 6422 except for the noted differences. Those portions of the elongate channel arrangement 6522 that are identical to portions of elongate channel arrangement 6422 will share the same element numbers. As can be seen in that Figure, the elongate channel 6522 includes a combination of a proximal most elongate indicator opening 6144P" that enables the clinician to view at least one foot or other portion of the cutting head assembly during the first stroke or actuation sequence of the firing trigger along with a combination of the round, equally-spaced indicator openings 6144. Thus, the elongate channel 6522 employs a combination of slotted and elongate slots. Any one of the above-described elongate channel arrangements may incorporate the light source 6160 that was specifically described herein in connection with the embodiment depicted in <figref idref="f0031">FIG. 33</figref> or they may be employed without a light source.

0145Other cutting head monitoring arrangements may comprise, one or more light source arrangements or light emitting diode ("LED") arrangements that cast light down the openings in the channel or down the slot inside of the channel. This would vastly increase the user's ability to locate where the cutting head is in its travels and determine whether the overall stroke is complete. In some arrangements, the LED's could comprise multi-colored LED's that change from green to blue (or other color arrangements) with the advancement of the cutting head down the channel further differentiating cutting head advancement.

0146In many end effector arrangements, it may be desirable to employ system for preventing the advancement or firing of the cutting head unless an unspent staple cartridge has been operably mounted in the elongate channel. For example, <patcit id="pcit0028" dnum="US6988649B"><text>U.S. Patent No. 6,988,649</text></patcit>, entitled SURGICAL STAPLING INSTRUMENT HAVING A SPENT CARTRIDGE LOCKOUT and <patcit id="pcit0029" dnum="US7044352B"><text>U.S. Patent No. 7,044,352</text></patcit>, entitled SURGICAL STAPLING INSTRUMENT HAVING A SINGLE LOCKOUT MECHANISM FOR PREVENTION OF FIRING disclose various lockout systems. In such lockout arrangements, the cutting head or "firing bar" is normally biased into a locked position by a spring arrangement. Until an unspent cartridge has been installed in the elongate channel, the cutting head cannot otherwise be advanced by the firing drive system of the surgical instrument.

0147Referring to <figref idref="f0035 f0036">FIGS. 40-42</figref>, there is shown a cutting head 6050 that is attached to a firing bar 6080. As shown, the firing bar 6080 is of laminate construction. However the firing bar 6080 may be of solid construction. In either case, the firing bar 6080 operably interfaces with the firing drive system of the surgical instrument as described herein or as is otherwise known. Actuation of the firing drive system axially advances the firing bar 6080 and cutting head 6050 attached thereto through the surgical staple cartridge that is mounted within the elongate channel 6122. The vertical portion 6052 of the cutting head 6050 includes a tissue cutting surface 6053 that is located between an upper end portion 6054 and a central hook portion 6056. See <figref idref="f0036">FIG. 42</figref>. An upper pin or upper tab 6058 extends laterally from each side of the upper end portion 6054. The upper tabs 6058 are configured to be slidably received within an upper passageway within an anvil that is operably mounted to the elongate channel as will be further discussed below.

0148<figref idref="f0035">FIG. 41</figref> illustrates the position of the cutting head 6050 and firing bar 6080 when a surgical staple cartridge is not present within the elongate channel 6122. When in that position, the firing bar 6080 and cutting head 6050 are biased in a downward direction "D" by a spring arm 6090 is supported by the shaft spine (not shown) that is coupled to the elongate channel 6122. As can be seen in that Figure, the spring arm 6090 is in sliding engagement with a spring tail 6082 that is formed in the distal end of the firing bar 6080. The bottom portion of the spring tail 6082 is biased into a sloped surface 6123 formed on the elongate channel 6122 when the cutting head 6050 is in that locked position as shown in <figref idref="f0035">FIG. 41</figref>. As can be further seen in <figref idref="f0035">FIG. 41</figref>, when the cutting head 6050 is in the locked position, if the clinician were to inadvertently try to advance or "fire" the cutting head 6050 distally through the elongate channel 6122, the lower feet or foot 6070 would contact the bottom of the elongate channel 6122. Stated another way, when the cutting head 6050 is in the locked position, the feet 6070 are not aligned with the internal passageway 6030 in the elongate channel 6122 and therefore the cutting head assembly 6050 could not be axially advanced therein. The clinician will know that the cutting head is locked by observing the position of the feet 6070 within the proximal opening 6040.

0149<figref idref="f0035">FIG. 40</figref> illustrates the position of the cutting head 6050 and firing bar 6080 when an unspent surgical staple cartridge has been operably supported within the elongate channel 6122. Although the body of the surgical staple cartridge is not shown in <figref idref="f0035">FIG. 40</figref>, a wedge sled assembly 6078 is shown. It will be understood that the wedge sled assembly 6078 will be in the position shown in <figref idref="f0035">FIG. 40</figref> in an unfired or unspent staple cartridge. When in that position, the wedge sled assembly 6078 engages with the hook portion 6056 on the cutting head 6050 to raise the cutting head 6050 in an upward direction (arrow "U" in <figref idref="f0035">FIG. 40</figref>) to a point wherein, when the cutting head 6050 is advanced distally, the feet 6070 thereon will enter the internal passage 6030 in the elongate channel 6122. When employing the elongate channels that have closed bottoms or substantially closed bottoms such as those described herein, a dimensional stack situation could conceivably occur wherein interference between the channel bottom and the knife foot or feet could occur when the end effector is used to cut and staple extremely thin tissue. If the tissue is too thin, the tissue compression resistance may not be enough to push the anvil away from the elongate channel and load those two components against the cutting head tabs. If this situation occurs, the knife foot or feet could extend below the bottom of the elongate channel far enough so that the cutting head could not be distally advanced. The cutting head assembly 6050 and elongate channel arrangement 6122 depicted in <figref idref="f0035">FIGS. 40 and 41</figref> may prevent this from happening.

0150As can be seen in <figref idref="f0035">FIGS. 40 and 41</figref>, the distal end of each foot 6070 may have a chamfer 6072 formed thereon. The chamfer 6072 is configured to engage corresponding portions of the elongate channel 6122 as the cutting head 6050 is advanced distally to cause the feet 6070 to enter the internal passage 6030. Thus the chamfers 6072 form small "lead-in" ramps which help to guide the feet 6070 into the passage 6030. As can also be seen in <figref idref="f0035">FIGS. 40 and 41</figref>, the portion of the elongate channel 6122 defining the proximal end 6131 of the internal passage 6030 may have a chamfer 6133 thereon or otherwise be sloped as shown. In alternative arrangements, the feet 6070 (or single foot) may be provided with the chamfer 6072 or the proximal end portion 6131 of the internal passage 6030 may be provided with the chamfer 6133 or both chamfer arrangements may be provided as shown in <figref idref="f0035">FIGS. 40 and 41</figref>.

0151<figref idref="f0037">FIGS. 43 and 44</figref> illustrate an end effector 7016 that may be similar, for example to end effector 16 or 300 or other end effectors disclosed herein. In this arrangement, the closure tube or sleeve 7028 has a series of indicator openings 7144 therein that enable the clinician to view the firing bar 6080 therethrough. The firing bar 6080 may be provided with a status mark 6084 thereon that may be viewed by the clinician through the indicator openings 7144 as the firing bar 6080 is advanced distally. The status mark 6084 may simply comprise a painted mark or other feature that would serve as a reference mark. In one arrangement, the status mark 6084 comprises one or more light emitting diodes (LED's) or other light source that is powered by a source of power in the surgical instrument or surgical system to which the end effector 7016 is attached.

0152<figref idref="f0038">FIG. 45</figref> illustrates another end effector 7016 wherein a closure sleeve segment 7030 includes an indicator window 7032 that enables the clinician to determine whether cutting head is in its locked position. In this arrangement, if the clinician can see the spring tail 6082 through the indicator window 7032, the cutting head is not in its locked position. If the clinician cannot see the spring tail 6082 through the indicator window 7032, the cutting head is in the locked position. In alternative arrangements, the indicator window 7032 maybe provided in such a location (e.g.; lower in the closure sleeve segment) such that if the spring tail 6082 is visible through the indicator window 7032, the cutting head is in its locked position and if the spring tail 6082 is not visible through the indicator opening, the cutting head is not in the locked position. To assist the clinician in determining the position of the cutting head, the cutting head may be provided in a particular bright or florescent color. These color arrangements may, be Radium based. Furthermore, the color of the cutting head may vary along its length to enable the clinician to easily ascertain its position.

0153<figref idref="f0039">FIG. 47</figref> illustrates an anvil 7020 that includes a plurality or series of indicator openings 7044 that provide viewing into a passage 7022 into which the upper end portion 6054 on the cutting head 6050 axially passes. In the embodiment depicted in <figref idref="f0039">FIG. 47</figref>, the indicator openings 7044 have a circular shape and are equally spaced along the length of the anvil 7020. In the embodiment depicted in <figref idref="f0039">FIG. 48</figref>, the indicator openings 7044 are spaced closer together at the proximal end of the anvil 7020. The spacing between the indicator openings 7044 gradually increases moving distally in the anvil 7020. The size, shape and spacing of the indicator openings 7044 may vary, however. Referring to <figref idref="f0036">FIG. 42</figref>, an indicator member 6059 may be provided in the top end portion 6054 of the cutting head 6050. The indicator member 6059 comprises one or more light emitting diodes or other light sources that may obtain power from the surgical instrument through a conductor 6081 that passes through the firing bar 6080. Such arrangement enables the clinician to view the position of the indicator member 6059 through the indicator openings 7044 in the anvil 7020 as the cutting head 6050 is advanced through the end effector. Alternatively, no indicator member (led, light) may be provided in the cutting head. However, the top end portion of the cutting head may be provided in a color or florescent marking that would make increase its visibility through the indicator openings in the anvil. For example, the color may be radium-based. The cutting head may alternatively be provided with laser scribed numbers to provide a means for determining the position of the cutting head within the channel or anvil.

0154The anvil 7020 depicted in <figref idref="f0039">FIG. 46</figref> employs an indicator system generally designated as 7200. In this embodiment, the indicator system 7200 includes a flexible strip or wave spring 7202 that is journaled at least at its proximal end 7204 in a slot 7021 provided in the anvil 7020. The wave spring 7202 extends the length of the anvil 7020 and is at least coextensive with the portion of the anvil 7020 that has the indicator openings 7044 therethrough. As can be seen in <figref idref="f0039">FIG. 46</figref>, a series of indicator members 7206 is attached to the flexible strip 7202 such that each indicator member 7206 is slidably supported in a corresponding indicator opening 7044. Each indicator member 7206 is initially supported in its corresponding indicator opening 7044 such that it does not protrude therefrom. Stated another way, the wave spring 7202 is configured such that the indicator members 7206 are biased into the initial position wherein they do not protrude out of their respective indicator opening 7044. However, as the cutting head 6050 is advanced distally through the end effector, the top portion 6054 of the cutting head 6050 slides along the bottom of the wave spring 7202 and serves to bias the wave spring 7202 upward such that, as the cutting head slides under a portion of the wave spring 7202 to which an indicator member 7206 is attached, the indicator member 7206 is caused to protrude out of the indicator opening 7044 as shown in <figref idref="f0039">FIG. 46</figref>. Thus, the clinician may monitor the position of the cutting head 6050 within the end effector by noting which indicator member 7206 is protruding out of its indicator opening 7044.

0155Thus, several of the elongate channel arrangements disclosed herein offer vast improvements over prior elongate channel arrangements. For example, at least some of the elongate channel arrangements do not employ an elongate slot that extends through the bottom surface of the channel. Thus, such elongate channel arrangements tend to be stiffer and resist spreading during operation. These advantages are also achieved while providing the clinician with a means for monitoring the progress of the cutting head. For example, some elongate channel arrangements provide periodic visibility along the length of the channel to inform the clinician of where the cutting head is in the firing cycle. At least some of the elongate channel arrangement also enables the clinician to see at least a portion of the cutting head when it is in the fully deployed position and a well as when the cutting head is in the fully retracted position. Furthermore at least some of the channel and/or anvil arrangements provide visibility of at least a portion of the cutting head from the side or top of the end effector or otherwise provide means for ascertaining the position of the cutting head from the side or top of the end effector.

0156As described above, a surgical staple cartridge operably supports a series of staple drivers therein that each support one or more surgical staples thereon. The staple drivers are supported in correspondingly-shaped staple pockets arranged in a linear orientation within the cartridge body. The surgical staples are movably supported on the drivers such that when the drivers are driven upward in the cartridge, the staples are driven through the tissue that is clamped between the cartridge and the anvil into forming contact with the underside of the anvil. When the anvil is opened, the staples remain with the stapled tissue. Because the staples are 'loosely" supported in their respective pockets on their staple drivers, they could conceivably fall out of the staple cartridge should the staple cartridge be inadvertently turned upside down prior to use. To avoid that from happening, cartridge covers are typically removably attached to the staple cartridge prior to use. When attached to the cartridge, the cartridge cover covers the staple pockets to retain the staples therein regardless of the position of the cartridge. When the clinician desires to install the cartridge into an end effector, the cover may be removed prior to installation.

0157As was further discussed above, the staple drivers are sequentially driven upward within the cartridge by a wedge sled that is driven distally with the cutting head assembly. In at least some arrangements, the wedge sled is therefore oriented in a proximal-most "starting" position in an unspent cartridge prior to firing. Indeed as was also discussed above, at least some arrangements require interaction between the wedge sled (when in its starting position) and the cutting head (when in its locked position) in order to move the cutting head out of the locked position to ready it for firing. In at least some prior arrangements, however, the cartridge lacked means or structure for ensuring that the wedge sled remained in its starting position prior to use. The cartridge cover 7250 depicted in <figref idref="f0054">FIGS. 64 and 65</figref> may address such problem.

0158<figref idref="f0054">FIG. 64</figref> illustrates a surgical staple cartridge 7220 that has a cartridge body 7222 that operably supports a plurality of staple drivers therein (not shown) on each lateral side of a longitudinally-extending slot 7224. The longitudinally-extending slot 7224 is configured to facilitate the longitudinal travel of a cutting head through the cartridge. As can be seen in <figref idref="f0054">FIG. 65</figref>, the cartridge 7220 also supports a wedge sled 7230 in a starting position adjacent the proximal end of the cartridge body 7222. <figref idref="f0054">FIGS. 64 and 65</figref> also illustrate a cartridge cover 7250 that includes a top portion 7252 that is configured to cover the cartridge deck 7226 when the cartridge cover 7250 is installed on the cartridge 7220. More specifically, the top portion 7252 is configured to cover all of the fastener cavity openings in the deck 7226 of the cartridge body 7222 when the top portion 7252 is in a "covering position". The cartridge cover 7250 is removably affixed to the staple cartridge 7220 by a pair of flexible attachment arms 7254 that are configured to retainingly engage the cartridge body 7222. The clinician may easily remove the cartridge cover 7250 by prying the flexible attachment arms 7254 out of retaining engagement with the cartridge body 7222. The cartridge cover 7250 further includes a pair of downwardly extending lateral side plates 7255 that serve to locate the cartridge cover 7250 in a desired position on the cartridge 7220. For example, the lateral side plates 7255 are positioned to engage a laterally extending lip 7227 formed on each side of the cartridge deck 7226. The cartridge cover 7250 also include a centrally-disposed locating fin 7256 that is orientated to be received within the longitudinally-extending slot 7224 when the cartridge cover 7250 is attached to the cartridge 7220 as shown in <figref idref="f0054">FIG. 65</figref>. The locating fin 7256 includes an engagement notch 7258 or other formation(s) that are configured to retainingly engage a portion of the wedge sled 7230 and retain the wedge sled 7230 in its starting position. Thus, when the cartridge cover 7250 is installed onto the staple cartridge 7220, the staples are retained within their respective pockets regardless of the orientation of the cartridge 7220. In addition, the wedge sled 7230 is retained in its starting position. The locating fin may be sized relative to the longitudinally-extending slot 7224 to establish a frictional fit therewith. In such arrangements, the frictional fit is employed to retain the cover 7250 in position on the cartridge 7220 without the need for the attachment arms 7254. Alternatively, the frictional fit established between the locating fin 7256 and the cartridge body 7222 as well as the attachment arms 7254 is employed to retain the cover 7250 on the cartridge body 7222 in the covering position. In addition, retention ribs 7257 are formed on the locating fin 7256 to further establish a frictional fit with the cartridge body 7222. Also, as can be seen in <figref idref="f0054">FIG. 65</figref>, the distal end 7221 of the surgical staple cartridge 7220 has a nose surface 7223 that is angularly oriented relative to the cartridge deck 7226. The cartridge cover 7250 also includes a nose portion 7251 that is configured to retainingly engage the distal end 7221 of the surgical staple cartridge 7220. For example, the nose portion 7251 may be configured to cover the nose surface 7223 of the cartridge 7220 and include a distal retention tab 7253 that is arranged to hookingly engage the distal end 7221 of the cartridge 7220. In addition, a detachment tab or protrusion 7259 is formed on the nose portion 7251 to facilitate detachment of the retention tab 7253 from the cartridge 7220. Thus, the distal end of the cartridge cover 7250 is configured to allow it to absorb the full force of a nose-down drop and transmit that force directly to the cartridge 7220 with as little longitudinal movement of the cover 7250 with respect to the cartridge body 7222. Such arrangements serves to prevent the cover 7250 from moving the sled 7230 proximally under such conditions. When the clinician desires to use the cartridge 7220, the cartridge cover 7250 is removed. In at least some arrangements, the cartridge cover 7250 may be provided in a particular color that corresponds to a size of staples that are received within the staple cartridge 7220.

0159As discussed in detail above, in various embodiments the surgical staples are supported on "drivers" that are operably supported in pockets that are formed into the body of the staple cartridge. Various forms of drivers may be employed. For example, a driver may be configured to support a single surgical staple, while other drivers may support multiple surgical staples. The drivers are supported in the cartridge body in longitudinally extending rows that are provided on each lateral side of the centrally-disposed elongate slot that accommodates passage of the cutting member or cutting head therethrough. As was previously discussed herein, the cutting head includes or cooperates with a wedge sled that is configured to sequentially contact the drivers to drive them upward in their respective pockets. As the driver moves upwardly in the staple cartridge, the surgical staple(s) supported thereon are driven upward through the tissue clamped between the cartridge and the anvil and into forming contact with the underside of the anvil.

0160As is known, the underside of the anvil includes a "staple-forming" surface that typically comprises a series of staple forming pockets that are arranged to be contacted by the ends of the staple legs. The pockets are situated and shaped such that when contacted by the staple legs, the legs are urged to bend around in the pocket to ultimately form a closed staple that roughly resembles a "B-shape". Misalignment of the staple legs during the forming process may cause the staple to become malformed which in severe cases may cause undesirable leakage. The staple driver configuration depicted in <figref idref="f0081">FIGS. 94 and 95</figref> may help to maintain staple alignment during the firing process. Furthermore, if during the firing process, the driver is not maintained in proper alignment within its respective pocket, higher firing forces must be generated to fire the staples supported thereon.

0161<figref idref="f0081">FIGS. 94 and 95</figref> depict a "double" staple driver 7300. As can be seen in those Figures, the staple driver 7300 includes a first driver portion 7310 and a second driver portion 7350 that are separated in a "staggered" orientation by a centrally disposed separator portion 7340. The staple driver 7300 may be of one-piece construction and, be molded from a suitable polymer material. The first driver portion 7310 includes a centrally disposed first cavity 7312 that divides the first driver 7310 into a first proximal upstanding support portion 7320 and a first distal upstanding support portion 7330. The first proximal upstanding support portion 7320 has a first proximal body portion 7321 that has an upper end 7322 that has a first proximal cradle section 7324 formed therein. Similarly, the first distal upstanding support portion 7330 has a first distal body portion 7331 that has a first distal end 7332 that has a first distal cradle section 7334 formed therein. The first proximal cradle section 7324 and first distal cradle section 7334 are aligned and configured to support the base of surgical staple therein. As can be further seen in <figref idref="f0081">FIG. 94</figref>, the first proximal upstanding support portion 7320 has a somewhat tapered shape when viewed from above. Stated another way, the first proximal upstanding support portion 7320 has a first proximal end 7326 that has a width "PW" that is less than a central width "CW" of the first proximal body portion 7321. Likewise, the first distal upstanding support portion 7330 has a first distal end 7336 that has a distal width "DW" that is less than a central width "CW" of the first distal body portion 7331. In at least one arrangement, the distal width "DW" is equal to the proximal width "PW".

0162Still referring to <figref idref="f0081">FIG. 94</figref>, the second driver portion 7350 includes a centrally disposed second cavity 7352 that divides the second driver portion 7310 into a second proximal upstanding support portion 7360 and a second distal upstanding support portion 7370. The second proximal upstanding support portion 7360 has a second proximal body portion 7361 that has an upper end 7362 that has a second proximal cradle section 7364 formed therein. Similarly, the second distal upstanding support portion 7370 has a second distal body portion 7371 that has a second distal end 7372 that has a second distal cradle section 7374 formed therein. The second proximal cradle section 7364 and second distal cradle section 7374 are aligned and configured to support the base of another surgical staple therein. As can be further seen in <figref idref="f0081">FIG. 94</figref>, the second proximal upstanding support portion 7360 has a somewhat tapered shape when viewed from above. Stated another way, the second proximal upstanding support portion 7360 has a proximal end 7366 that has a width "PW" that is less than a central width "CW" of the second proximal body portion 7361. Likewise, the second distal upstanding support portion 7370 has a distal end 7376 that has a distal width "DW" that is less than a central width "CW" of the second distal body portion 7371. Thus, the first driver portion 7310 and the second driver portion 7350 have similar shapes.

0163To provide the staple driver 7300 with more stability during the firing process, the first and second driver portions 7310, 7350 are further provided with stabilizer arrangements that cooperate with complementary-shaped staple pockets in the staple cartridge body. For example, the first staple driver portion 7310 has a first proximal set 7327 of laterally-protruding support columns 7328, 7329 formed on the first proximal end 7326 thereof. A first distal set 7337 of laterally-protruding support columns 7338, 7339 are also provided on the first distal end 7336 of the first distal upstanding support portion 7330 as shown. Likewise, the second staple driver portion 7350 has a second proximal set 7367 of laterally-protruding support columns 7368, 7369 formed on the second proximal end 7366 thereof. A second distal set 7377 of laterally-protruding support columns 7378, 7379 are also provided on the second distal end 7376 of the second distal upstanding support portion 7370 as shown.

0164As indicated above, the staple driver 7300 is movably supported with a complimentary shaped staple pocket in the staple cartridge. As the wedge sled is driven distally, a corresponding portion thereof drivingly contacts the centrally disposed separator portion 7340 and drives the driver 7300 upward. Each of the laterally-protruding support columns 7328, 7329, 7338, 7339, 7368, 7369, 7378 and 7379 are received in correspondingly-shaped grooves in the staple cartridge body and serve to maintain the alignment of the driver 7300 and prevent twisting thereof during its advancement toward the anvil. In one arrangement, the driver 7300 is molded or otherwise formed from solid material. Alternatively, however, the first driver portion 7310 and the second driver portion 7350 may be hollow to enable those portions of the driver 7300 to be somewhat flexible and compliant to further maintain the alignment of the driver in its respective pocket and thereby further reduce the driving force required. In either arrangement, by providing the alignment columns on both ends of both driver portions, alignment of the driver within its respective pocket is further enhanced.

0165<figref idref="f0082">FIG. 96</figref> depicts another "double" staple driver 7400 that is configured to be received in a complementary-shaped staple pocket formed in the body of a surgical staple cartridge. As can be seen in <figref idref="f0082">FIG. 96</figref>, the staple driver 7400 includes a first driver portion 7410 and a second driver portion 7450 that are separated in a "staggered" orientation by a centrally disposed separator portion 7440. The staple driver 7400 may be of one-piece construction and, be molded from a suitable polymer material. The first driver portion 7410 includes a centrally disposed first cavity 7412 that divides the first driver 7410 into a first proximal upstanding support portion 7420 and a first distal upstanding support portion 7430. The first proximal upstanding support portion 7420 has a first proximal body portion 7421 that has an upper end 7422 that has a first proximal cradle section 7424 formed therein. Similarly, the first distal upstanding support portion 7430 has a first distal body portion 7431 that has a first distal end 7432 that has a first distal cradle section 7434 formed therein. The first proximal cradle section 7424 and first distal cradle section 7434 are aligned and configured to support the base of surgical staple therein. As can be further seen in <figref idref="f0082">FIG. 96</figref>, the first proximal upstanding support portion 7420 and the first distal upstanding support portion each have has a somewhat tapered shape.

0166Still referring to <figref idref="f0082">FIG. 96</figref>, the second driver portion 7450 includes a centrally disposed second cavity 7452 that divides the second driver portion 7450 into a second proximal upstanding support portion 7460 and a second distal upstanding support portion 7470. The second proximal upstanding support portion 7460 has a second proximal body portion 7461 that has an upper end 7462 that has a second proximal cradle section 7464 formed therein. Similarly, the second distal upstanding support portion 7470 has a second distal body portion 7471 that has a second distal end 7472 that has a second distal cradle section 7474 formed therein. The second proximal cradle section 7464 and second distal cradle section 7474 are aligned and configured to support the base of another surgical staple therein.

0167To provide the staple driver 7400 with more stability during the firing process, the first and second driver portions 7410, 7450 are further provided with stabilizer arrangements that cooperate with complementary-shaped staple pockets in the staple cartridge body. For example, the first staple driver portion 7410 has a first proximal set 7427 of laterally-protruding support columns 7428, 7429 formed on the first proximal body portion 7421. A first distal set 7437 of laterally-protruding support columns 7438,7439 are also provided on the first distal body portion 7431 of the first distal upstanding support portion 7430 as shown. Likewise, the second staple driver portion 7450 has a second proximal set 7467 of laterally-protruding support columns 7468, 7469 formed on the second proximal body portion 7461. A second distal set 7477 of laterally-protruding support columns 7478, 7479 are also provided on the second distal body portion 7471 of the second distal upstanding support portion 7470 as shown.

0168The staple driver 7400 is movably supported with a complimentary-shaped staple pocket in the staple cartridge. As the wedge sled is driven distally, a corresponding portion thereof drivingly contacts the centrally disposed separator portion 7440 and drives the driver 7400 upward. Each of the laterally-protruding support columns 7428, 7429, 7438, 7439, 7468, 7469, 7478 and 7479 are received in correspondingly-shaped grooves in the staple cartridge body and serve to maintain the alignment of the driver 7400 and prevent twisting thereof driving its advancement toward the anvil. In one arrangement, the driver 7400 is molded or otherwise formed from solid material. Alternatively, however, the first driver portion 7410 and the second driver portion 7450 may be hollow to enable those portions of the driver 7400 to be somewhat flexible and compliant to further maintain the alignment of the driver in its respective pocket and thereby further reduce the driving force required. In either arrangement, by providing the alignment columns on both ends of both driver portions, alignment of the driver within its respective pocket is further enhanced.

0169<figref idref="f0082">FIG. 97</figref> illustrates a staple or driver pocket 7510 that is formed in a body portion 7502 of a staple cartridge 7500. This staple or driver pocket 7510 is configured to operably support a complementary-shaped "single" staple driver therein. As can be seen in that Figure, the staple pocket 7510 is formed with two inwardly-extending proximal column members 7512, 7514 and two inwardly extending distal columns 7516, 7518. The columns 7512, 7514, 7516 and 7518 are configured to slidably extend into corresponding lateral grooves provided in the staple driver. Such driver pocket configurations serve to provide further stabilization and alignment of the driver as it is driven from the pocket. Although <figref idref="f0082">FIG. 97</figref> illustrates a staple or driver pocket that is configured to operably support a single staple driver therein, the same concept may be applied to those driver pockets that are configured to support drivers that are constructed to support multiple surgical staples. For example, the support columns employed in the driver embodiments illustrated in <figref idref="f0081 f0082">FIGS. 94-96</figref> may be replaced with grooves that are configured to slidably receive corresponding columns formed in the sides of the staple pockets in the cartridge body.

0170As illustrated in <figref idref="f0081 f0082">FIGS. 94-96</figref>, various driver arrangements essentially may include a driver body or driver body portion that includes an outer surface as well as a leading and trailing end. The outer surface may be sized and shaped to avoid contact with any portions of the inner wall of the staple pocket in which is it movably supported - except for the laterally extending features/support columns formed thereon. For example, the double staple driver 7400 depicted in <figref idref="f0082">FIG. 96</figref> includes a first driver portion 7410 and a second driver portion 7450. The first driver portion 7410 and the second driver portion 7450 may be sized relative to a staple pocket such that the only portions that are in contact with the inner wall of the staple pocket are the laterally extending features formed thereon such as elements 7428, 7429, 7438, 7439, 7468, 7469. The proximal-most end of the first driver portion 7410 may comprise the "leading end" and the distal-most end of the second driver portion 7450 may comprise the "trailing end". In still another arrangement, the leading end and the trailing end may be sized relative to the corresponding portions of the staple pocket in which they are received such that the clearance between those ends and their corresponding pocket portions is less than the clearance between the other driver portions and the other portions of the staple pocket. Such amounts of clearance may be sized to improve lateral stability of the driver during actuation without establishing a frictional fit between the outer surface of the driver and the inner wall of the staple pocket. In another arrangement, the driver may be configured (e.g., sized and shaped) relative to the staple pocket such that the only portion(s) of the driver that contact the inner wall portions of the staple pocket consist of one or more formations (support columns) on the leading and/or the trailing ends of the driver. Conversely, one or more grooves may be provided in the leading and/or trailing ends that are configured to receive corresponding formations on the inner wall portions of the staple pocket - with those formations being the only point(s) of contact between the driver and the inner walls of the staple pocket during actuation of the driver. As indicated above, the drivers may generally be supported in the cartridge body in longitudinally extending rows of staple pockets that are provided on each lateral side of the centrally-disposed elongate slot that accommodates passage of the cutting member or cutting head therethrough. In certain arrangements, the various drivers disclosed herein that employ one or more support columns/laterally extending features may be employed in one or more longitudinal rows of staple pockets (or portions of longitudinal rows) on one or both sides of the elongate slot. For example, the row of staple pockets on each side of the elongate slot that is the closest to the edge of the cartridge body may include drivers that employ the support column/laterally extending formations, but the other rows of staple pockets may employ conventional drivers. This arrangement may also be employed with staple pockets 7510. That is, the staple pockets 7510 may only be employed in certain longitudinal rows of staple pockets (or portions of longitudinal lines) on one or both sides of the elongate slot.

0171Tissue flow can be one of the contributing issues to staple malformations. During stapling, the tissue flows both distally and laterally, with the lateral motion being more detrimental that the longitudinal. With tissue flow and high compressive forces, the staples are directed laterally and distally from their respective pockets. By tightening up the fit between the driver and the portions of the cartridge adjacent to it, the staple has less ability to rock to the side or front during firing because the driver also has less ability to rock. The various driver and staple pocket arrangements disclosed herein serve to minimize such rocking. The support columns/laterally extending features disclosed herein may be provided on all of the drivers or simply to drivers in specific regions (e.g., the drivers in the outer rows within the cartridge). Such support columns/laterally extending features may be on the sides of the driver, the ends of the driver or both. The term "support column" as used to describe the driver stabilization arrangements disclosed herein encompasses the various laterally extending, vertically-elongate formations as shown in the present Figures. The term "support column" may also encompass a variety of differently-shaped laterally extending features that are configured to be movably received in correspondingly shaped grooves provided in the inner wall of the staple pocket (in arrangements wherein the support columns/laterally extending features are on the driver) or in the various driver portions (in arrangements wherein the support columns/laterally extending features protrude from the inner walls of the staple pocket), whichever the case may be. A support column may, comprise a single laterally extending feature or it may comprise a plurality of aligned laterally extending features. For example, a support column may consist of column segments or aligned portions/formations. In still other arrangements, other protrusion shapes may be employed.

0172With regard to the various examples describedherein, a fastener cartridge includes a layer of material which is implantable into a patient. Such a layer comprises one or more pieces of buttress material and/or one or more tissue thickness compensators. Turning now to <figref idref="f0084 f0085">FIGS. 99-102</figref>, a staple cartridge 8000 includes a cartridge body 8010 and an implantable layer 8020. The cartridge body 8010 includes a proximal end 8012, a distal end 8014, and a deck 8016 extending between the proximal end 8012 and the distal end 8014. The deck 8016 is configured to support tissue when the tissue is clamped between the staple cartridge 8000 and an anvil. The cartridge body 8010 further includes fastener cavities defined therein which are each configured to store a fastener, such as a staple, therein. Each fastener cavity includes a proximal end and a distal end. The proximal end of each fastener cavity is closer to the proximal end 8012 of the cartridge body 8010 than the distal end of each fastener cavity and, correspondingly, the distal end of each fastener cavity is closer to the distal end 8014 of the cartridge body 8010.

0173The cartridge body 8010 comprises projections extending from the deck 8016. The projections can be arranged in any suitable arrangement. For instance, distal projections 8017 can be positioned adjacent the distal ends of the fastener cavities while proximal projections 8019 can be positioned adjacent the proximal ends of the fastener cavities. The distal projections 8017 and/or the proximal projections 8019 are configured to guide the fasteners stored in the fastener cavities as the fasteners are ejected from the fastener cavities. In such instances, the distal projections 8017 and/or the proximal projections 8019 can extend the fastener cavities above the deck 8016. Some fastener cavities may have an adjacent distal projection 8017 and a proximal projection 8019 while other fastener cavities may only have one or the other. Some fastener cavities may have neither a distal projection 8017 nor a proximal projection 8019 associated therewith.

0174Layer 8020 comprises a layer body 8026 which includes a proximal end 8022 and a distal end 8024. The proximal end 8022 of the layer body 8026 is positioned adjacent or relative to the proximal end 8012 of the cartridge body 8010 and the distal end 8024 is positioned adjacent or relative to the distal end 8014. In certain instances, the layer 8026 comprises a solid sheet of material. The layer body 8026 can extend over one or more fastener cavities defined in the cartridge body 8010. For example, the layer body 8026 includes portions 8025 which extend over the fastener cavities. When the fasteners are ejected from the fastener cavities, the fasteners can capture the portions 8025 therein thereby retaining the layer 8020 to the tissue. In some instances, the layer body 8026 comprises openings aligned with some of the fastener cavities in the cartridge body 8010.

0175The layer body 8026 comprises apertures defined therein which are aligned with the projections extending from the deck 8016. For instance, the layer body 8026 comprises distal apertures 8027 which are aligned with at least some of the distal projections 8017 and/or proximal apertures 8029 which are aligned with at least some of the distal projections 8019. The distal apertures 8027 and the distal projections 8017 can be sized and configured such that there is clearance therebetween. Similarly, the proximal apertures 8029 and the proximal projections 8019 can be sized and configured such that there is clearance therebetween. In some instances, the distal apertures 8027 and the distal projections 8017 can be sized and configured such that there is an interference fit therebetween. Also, similarly, the proximal apertures 8029 and the proximal projections 8019 can be sized and configured such that there is an interference fit therebetween. For example, the interference fit between the projections and the apertures can releasably retain the layer 8020 to the cartridge body 8010. In use, the fasteners stored in the cartridge body 8010 can contact the portions 8025 of the layer 8020 as the fasteners are ejected from the cartridge body 8010 and lift the layer 8020 away from the deck 8016 and disengage the apertures from the projections.

0176The layer body 8026 includes apertures 8028 which are each configured to receive a distal projection 8017 and a proximal projection 8019 therein. Each aperture 8028 comprises an elongate slot having a proximal end configured to receive a distal projection 8017 and a distal end configured to receive a proximal projection 8019. In some instances, a clearance fit may be present between the apertures 8028 and the projections 8017 and 8019. In certain instances, an interference fit may be present between the apertures 8028 and the projections 8017 and 8019 to releasably retain the layer 8020 to the cartridge body 8010. For example, the apertures 8028 can be sized and configured to stretch to accommodate a distal projection 8017 and a proximal projection 8019 therein.

0177The layer 8020 can be removably affixed to the cartridge body 8010. In certain instances, the distal end 8024 of the layer 8020 can be removably attached to the distal end 8014 of the cartridge body 8010. In some instances, the proximal end 8022 of the layer 8020 can be removably attached to the proximal end 8012 of the cartridge body 8010. In at least one example, attachment portions 8021 can be utilized to releasably hold the layer 8020 to the cartridge body 8010.

0178A layer, such as buttress material, may be made from any biocompatible material. Buttress material may be formed from a natural material and/or a synthetic material. Buttress material may be bioabsorbable and/or non-bioabsorbable. It should be understood that any combination of natural, synthetic, bioabsorbable and non-bioabsorbable materials may be used to form buttress material. Some non-limiting examples of materials from which the buttress material may be made include, but are not limited to, poly(lactic acid), poly (glycolic acid), poly (hydroxybutyrate), poly (phosphazine), polyesters, polyethylene glycols, polyethylene oxides, polyacrylamides, polyhydroxyethylmethylacrylate, polyvinylpyrrolidone, polyvinyl alcohols, polyacrylic acid, polyacetate, polycaprolactone, polypropylene, aliphatic polyesters, glycerols, poly(amino acids), copoly (ether-esters), polyalkylene oxalates, polyamides, poly (iminocarbonates), polyalkylene oxalates, polyoxaesters, polyorthoesters, polyphosphazenes and copolymers, block copolymers, homopolymers, blends and/or combinations thereof.

0179Natural biological polymers can be used in forming the buttress material. Suitable natural biological polymers include, but are not limited to, collagen, gelatin, fibrin, fibrinogen, elastin, keratin, albumin, hydroxyethyl cellulose, cellulose, oxidized cellulose, hydroxypropyl cellulose, carboxyethyl cellulose, carboxymethyl cellulose, chitan, chitosan, and/or combinations thereof. Natural biological polymers may be combined with any of the other polymeric materials described herein to produce the buttress material. Collagen of human and/or animal origin, e.g., type I porcine or bovine collagen, type I human collagen or type III human collagen may be used to form the buttress material. The buttress material may be made from denatured collagen or collagen which has at least partially lost its helical structure through heating or any other method, consisting mainly of non-hydrated a chains, of molecular weight close to 100 kDa. The term "denatured collagen" means collagen which has lost its helical structure. The collagen used for the porous layer as described herein may be native collagen or atellocollagen, notably as obtained through pepsin digestion and/or after moderate heating as defined previously. The collagen may have been previously chemically modified by oxidation, methylation, succinylation, ethylation and/or any other known process.

0180Where the buttress material is fibrous, the fibers may be filaments or threads suitable for knitting or weaving or may be staple fibers, such as those frequently used for preparing non-woven materials. The fibers may be made from any biocompatible material. The fibers may be formed from a natural material or a synthetic material. The material from which the fibers are formed may be bioabsorbable or non-bioabsorbable. It should be understood that any combination of natural, synthetic, bioabsorbable and non-bioabsorbable materials may be used to form the fibers. Some non-limiting examples of materials from which the fibers may be made include, but are not limited to, poly(lactic acid), poly (glycolic acid), poly (hydroxybutyrate), poly (phosphazine), polyesters, polyethylene glycols, polyethylene oxides, polyacrylamides, polyhydroxyethylmethylacrylate, polyvinylpyrrolidone, polyvinyl alcohols, polyacrylic acid, polyacetate, polycaprolactone, polypropylene, aliphatic polyesters, glycerols, poly(amino acids), copoly (ether-esters), polyalkylene oxalates, polyamides, poly (iminocarbonates), polyalkylene oxalates, polyoxaesters, polyorthoesters, polyphosphazenes and copolymers, block copolymers, homopolymers, blends and/or combinations thereof. Where the buttress material is fibrous, the buttress material may be formed using any method suitable to forming fibrous structures including, but not limited to, knitting, weaving, non-woven techniques and the like. Where the buttress material is a foam, the porous layer may be formed using any method suitable to forming a foam or sponge including, but not limited to the lyophilization or freeze-drying of a composition.

0181The buttress material may possesses haemostatic properties. Illustrative examples of materials which may be used in providing the buttress material with the capacity to assist in stopping bleeding or hemorrhage include, but are not limited to, poly(lactic acid), poly(glycolic acid), poly(hydroxybutyrate), poly(caprolactone), poly(dioxanone), polyalkyleneoxides, copoly(ether-esters), collagen, gelatin, thrombin, fibrin, fibrinogen, fibronectin, elastin, albumin, hemoglobin, ovalbumin, polysaccharides, hyaluronic acid, chondroitin sulfate, hydroxyethyl starch, hydroxyethyl cellulose, cellulose, oxidized cellulose, hydroxypropyl cellulose, carboxyethyl cellulose, carboxymethyl cellulose, chitan, chitosan, agarose, maltose, maltodextrin, alginate, clotting factors, methacrylate, polyurethanes, cyanoacrylates, platelet agonists, vasoconstrictors, alum, calcium, RGD peptides, proteins, protamine sulfate, epsilon amino caproic acid, ferric sulfate, ferric subsulfates, ferric chloride, zinc, zinc chloride, aluminum chloride, aluminum sulfates, aluminum acetates, permanganates, tannins, bone wax, polyethylene glycols, fucans and/or combinations thereof. The use of natural biological polymers, and in particular proteins, may be useful in forming buttress material having haemostatic properties. Suitable natural biological polymers include, but are not limited to, collagen, gelatin, fibrin, fibrinogen, elastin, keratin, albumin and/or combinations thereof. Natural biological polymers may be combined with any other haemostatic agent to produce the porous layer of the buttress.

0182Although the various embodiments of the devices have been described herein in connection with certain disclosed embodiments, many modifications and variations to those embodiments may be implemented. Also, where materials are disclosed for certain components, other materials may be used. Furthermore, according to various embodiments, a single component may be replaced by multiple components, and multiple components may be replaced by a single component, to perform a given function or functions. The foregoing description and following claims are intended to cover all such modification and variations.

0183The devices disclosed herein can be designed to be disposed of after a single use, or they can be designed to be used multiple times. In either case, however, the device can be reconditioned for reuse after at least one use. Reconditioning includes any combination of the steps of disassembly of the device, followed by cleaning or replacement of particular pieces, and subsequent reassembly. In particular, the device can be disassembled, and any number of the particular pieces or parts of the device can be selectively replaced or removed in any combination. Upon cleaning and/or replacement of particular parts, the device can be reassembled for subsequent use either at a reconditioning facility, or by a surgical team immediately prior to a surgical procedure. Those skilled in the art will appreciate that reconditioning of a device can utilize a variety of techniques for disassembly, cleaning/replacement, and reassembly. Use of such techniques, and the resulting reconditioned device, are all within the scope of the present application.

0184Preferably, the invention described herein will be processed before surgery. First, a new or used instrument is obtained and if necessary cleaned. The instrument can then be sterilized. In one sterilization technique, the instrument is placed in a closed and sealed container, such as a plastic or TYVEK bag. The container and instrument are then placed in a field of radiation that can penetrate the container, such as gamma radiation, x-rays, or high-energy electrons. The radiation kills bacteria on the instrument and in the container. The sterilized instrument can then be stored in the sterile container. The sealed container keeps the instrument sterile until it is opened in the medical facility.