Vessel sealer and divider

ES 2 348 664 T3

- 1 DESCRIPTION

BACKGROUND

The present specification relates to an electrosurgical instrument and a method for performing endoscopic surgical procedures, and more particularly, this specification relates to open or endoscopic bipolar electrosurgical forceps or forceps, and to a method for sealing and / or cutting tissue.

Technical field

A forceps or hemostat is a simple forceps-like tool that uses mechanical action between its jaws to press vessels, and is commonly used in open surgical procedures to grasp, cut, and / or clamp tissue. Electrosurgical forceps utilize both mechanical clamping action and electrical energy to effect hemostasis by heating tissue and vessels, to coagulate, cauterize, and / or seal tissues.

In recent decades, many surgeons have supplemented traditional open methods of gaining access to vital organs and body cavities with endoscopes and endoscopic instruments that access organs through small, needle-like incisions. Endoscopic instruments are inserted into the patient through a cannula or through an opening made with a trocar. Typical cannula sizes are in the range of three to twelve millimeters. Smaller cannulas are generally preferred, which, as can be appreciated, presents a challenge for manufacturers in terms of instrument design, which must allow surgical instruments to penetrate through the cannulas.

Certain endoscopic surgical procedures require cutting of blood vessels or vascular tissue. However, due to space limitations, surgeons may have difficulty suturing vessels or performing other traditional methods of bleeding control, for example, clamping and / or ligating severed blood vessels. These blood vessels, within a range of less than two millimeters in diameter, can often be closed using standard electrosurgical techniques. However, if a larger vessel is cut, it may be necessary for the surgeon to convert the endoscopic procedure to an open surgical procedure, thereby not taking advantage of the benefits of laparoscopy.

Several journal articles have discussed methods of plugging small blood vessels with the use of electrosurgery. An article entitled Studies on coagulation and the development of an automatic computerized bipolar coagulator.

ES 2 348 664 T3

- 2 coagulation and development of a computerized automatic bipolar coagulator), J. Neurosurg. Magazine, vol. 75, July 1991, describes a bipolar coagulator that is used to seal small blood vessels. The article says that arteries with a diameter greater than 2 - 2.5 mm cannot be safely coagulated. A second article titled Automatically Controlled Bipolar Electrocoagulation - COA-COMP (Automatically controlled bipolar electrocoagulation), Neurosurg magazine. Rev. (1984), pp. 187 to 190, describes a method for the final connection of electrical energy to the vessel, so as to avoid scorching the walls of said vessel.

As previously stated, by using an electrosurgical forceps, a surgeon can cauterize, coagulate / desiccate, and / or simply reduce or delay bleeding, by controlling the intensity, frequency, and duration of the electrosurgical energy applied to the weaving through the jaw members. The electrode of each jaw member is charged with a different electrical potential, so that when the jaw members grip tissue, electrical energy can be selectively transferred through tissue.

To properly seal larger vessels, two predominant mechanical parameters must be precisely controlled: the pressure applied to the vessel and the gap distance between the electrodes, the parameters of which are affected by the thickness of the sealed vessel. More particularly, accurate application of pressure to opposing vessel walls is important to: reduce tissue impedance to a value low enough to allow adequate electrosurgical energy through tissue; avoid expansion forces during heating of the fabric; and contribute to the completion of tissue thickening, which is an indication of a good seal. The optimal wall of a molten vessel has been determined to be between 0.025 and 0.127 mm. Below this range the seal may come undone or tear, and above that the lumens may not be properly or effectively sealed.

With respect to smaller vessels, the pressure applied to the tissue tends to be less relevant, while the distance or separation between the electrically conductive surfaces becomes more significant to effect sealing. In other words, the chances of the two electrically conductive surfaces touching during activation increases as the vessels are smaller.

Electrosurgical methods may be able to seal larger vessels with the use of a suitable electrosurgical energy curve, coupled to an instrument capable of applying a large closing force to the vessel walls. The small vessel coagulation procedure is considered to be fundamentally different from

ES 2 348 664 T3

- 3 electrosurgical obturation of the vessels. For the present purposes, the term coagulation is defined as a tissue desiccation procedure, in which the cells of said tissue are disrupted and dried. Vessel obturation is defined as the procedure for liquefying collagen in tissue so that it becomes a melt. Therefore, the coagulation of small vessels is sufficient to permanently close them. Larger vessels need to be sealed to ensure permanent closure.

US Patent Nos. 2,176,479 to Wills; Nos. 4,005,714 and 4,031,898 to Hiltebrandt; Nos. 5,827,274, 5,290,287, and 5,312,433 to Boebel et al .; Nos. 4,370,980, 4,552,143, 5,026,370, and 5,116,332 to Lottick; no. 5,443,463 to Stem et al .; No. 5,484,436 to Eggers et al .; and no. 5,951,549 to Richardson et al., All relate to electrosurgical instruments for coagulating, cutting, and / or sealing vessels or tissue. However, some of these designs may not provide a uniformly reproducible pressure to the blood vessel, and may result in ineffective or non-uniform sealing.

Many of these instruments include blade members or shear members, which simply mechanically and / or electromechanically cut tissue, and are relatively ineffective for vessel sealing purposes. Other instruments rely only on clamping pressure to provide appropriate sealing thicknesses, and are not designed to take into account tolerances in the gap and / or parallelism and flattening requirements, which are parameters that if properly controlled can ensure a uniform and effective tissue seal. For example, it is known that it is difficult to adequately control the thickness of the resulting sealed tissue by controlling the clamping pressure alone, for either of the following two reasons: 1) If too much force is applied there is a possibility that the poles will touch and that the energy is not transferred through the tissue, resulting in an ineffective seal; or 2) if too low a force is applied, the tissue can be moved prematurely before activation and sealing, and a thicker and less reliable seal can be created.

As stated above, to properly and effectively seal larger vessels, a greater closing force is required between the opposing jaw members. It is known that a large clamping force between the jaws typically requires a large moment about the jaw box pivot. This is a problem as the jaw members are typically secured with pins positioned to have small moment arms relative to the pivot of each jaw member. A large force applied to a small moment arm is undesirable, because large forces

ES 2 348 664 T3

- 4 can shear the pins. As a result, designers must compensate for these large closing forces, by designing the instruments with metal pins, and / or by designing such instruments so that said closing forces are at least partially relieved, to reduce the chances of failure. mechanical. As can be appreciated, if metal pivot pins are employed, they must be insulated to prevent them from acting as an alternate current path between the jaws, which can be detrimental to an effective seal.

Increasing the closing forces between the electrodes can have other undesirable effects, for example, it can cause opposing electrodes to come into contact proximity with each other, which can result in a short circuit, and a small closing force can cause premature tissue movement during compression and prior to activation.

Typically, and particularly with respect to endoscopic electrosurgical procedures, once a vessel has been sealed, the surgeon must remove the obturator instrument from the surgical site, replace it with a new instrument through the cannula, and cut accurately the vessel along the newly formed tissue seal. As can be appreciated, this additional operation can be time consuming (particularly when a significant number of vessels are plugged), and can contribute to inaccurate tissue separation throughout the plugging, due to misalignment or inaccurate placement of the tube. cutting instrument along the center of the tissue filling line.

Various attempts have been made to design an instrument that incorporates a blade or knife member that effectively cuts tissue after forming a seal therein. For example, US Patent No. 5,674,220 to Fox et al. discloses a transparent instrument for vessel sealing that includes a reciprocating longitudinally displacing blade, which cuts through tissue once sealed. The instrument includes a plurality of openings that allow direct visualization of the tissue during the obturation and cutting procedure. This direct visualization allows a user to manually view and regulate the clamping force and gap distance between the jaw members, to reduce and / or limit certain undesirable visual effects known to occur when vessels are plugged, such as thermal expansion. , scorching, etc. As can be appreciated, the overall success in creating an effective tissue seal with this instrument is based primarily on the experience, vision, and dexterity of the user, as well as experience in estimating the appropriate closing force, separation distance. , and offset length

ES 2 348 664 T3

- 5 alternative of the blade to seal the vessel in a uniform, coherent, and effective way, and to separate the tissue in the seal along an ideal cutting plane.

US Patent No. 5,702,390 to Austin et al. describes a vessel sealing instrument that includes a triangular shaped electrode rotatable from a first position to seal tissue to a second position to cut it. Again, the user must rely on direct visualization and experience to control the various effects of tissue sealing and cutting.

EP 0640 317 discloses an electrosurgical device for cauterizing and fusing tissue. The preamble of claim 1 is based on this document.

WO 0024331 discloses surgical bipolar forceps that include a stop member attached to the jaw members to control the distance between them.

Thus, there is a need to develop an electrosurgical instrument that effectively and evenly seals and separates vascular tissue, and that solves many of the aforementioned problems known in the art.

Document WO-A-01/17 448 describes an electrosurgical apparatus according to the preamble of claim 1.

SUMMARY

The present invention is defined in claim 1.

This specification refers to bipolar electrosurgical forceps or forceps for grasping, sealing, and dividing tissue, as defined in claim 1. More particularly, the present specification refers to a bipolar electrosurgical forceps that gives consistency to the general clamping pressure exerted on a tissue, between opposing jaw members, regulates the separation distances between opposing jaw members, reduces the chances of a short circuit. between said opposing jaw members during activation, includes non-conductive stop members that aid in handling, gripping, and tissue clamping prior to and during tissue activation and division, and providing a uniquely designed path for the electrical wire through the instrument body and into the opposing jaw members to reduce potential activation irregularities during activation. manipulation, sealing, and division of tissue.

The forceps described herein refers to an electrosurgical instrument for sealing and / or dividing tissue, and includes a housing that has

ES 2 348 664 T3

- 6 a shaft attached to it defining a longitudinal axis, and a first jaw member movable with respect to a second jaw member. The first jaw member is attached to the shaft, and moves from a first open position in which said jaw member is disposed in spaced relationship with respect to the other, and a second closed position in which the jaw members cooperate to grip the fabric between them.

The instrument also includes a drive rod assembly that imparts movement to the jaw members between said first and second positions, a rotation assembly that rotates the jaw members about the longitudinal axis, and a blade assembly that separates the jaw. tissue gripped between the jaw members. Also included is a four-bar grip assembly, which includes a grip and a cam-like piston that cooperate to impart uniform closing pressure against tissue gripped between the jaw members. The forceps includes a blade assembly attached to the housing to separate tissue trapped between the jaw members. The forceps includes at least one conductive stop member disposed on an inwardly turned surface of at least one of the jaw members, defining a gap between the sealing surfaces during sealing. A pair of electrical conductors can connect the jaw members to a source of electrical power, and include loose loops provided in the turning assembly, which allow the jaw members to rotate about the longitudinal axis.

In one embodiment, the first and second jaw members are pivotally movable relative to each other, and are rotatable substantially 360 ° about the longitudinal axis. Preferably, the handle and cam member of the four-bar mechanical link cooperate with a spring to create uniform closing pressure against tissue gripped between the jaw members.

In another embodiment, the handle is lockable within the housing, to selectively lock the jaw members together. Preferably, the blade assembly is variable from one locked configuration to another without locking with movement of the four-bar mechanical linkage. For example, the handle may include an elongated pin that is reciprocated within a channel disposed within the housing, which channel has predefined overall dimensions. Said pin is dimensioned to cooperate with the predefined internal dimensions of the channel, to selectively lock the jaw members together, and to unlock the blade assembly.

In yet another embodiment, one of the jaw members includes a longitudinal channel defined at least partially therethrough, which allows movement

ES 2 348 664 T3

- 7 alternative of the blade assembly along an ideal cutting plane for tissue separation. In another embodiment, the pivot assembly includes a mechanical intermediate surface, eg, a retainer, that cooperates with a corresponding mechanical intermediate surface, eg, a notch, disposed in the housing to prevent excessive rotation of the jaw members. .

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of this instrument are described below with reference to the accompanying drawings, in which:

-Fig. 1A is a left perspective view of an endoscopic bipolar forceps, showing a housing, shaft, and end actuation assembly, in accordance with this specification;

-Fig. 1B is a left perspective view of an open bipolar forceps, in accordance with this specification;

-Fig. 2 is a top view of the forceps of FIG. 1;

-Fig. 3 is a right side view of the forceps of FIG. 1;

-Fig. 4 is a right perspective view of the forceps of FIG. 1, showing rotation of the end actuation assembly about a longitudinal axis A;

-Fig. 5 is a front view of the forceps of FIG. 1;

-Fig. 6 is an enlarged view of the area of ​​detail indicated in FIG. 5, which shows the end actuation assembly enlarged, with details of the pair of opposing jaw members;

-Fig. 7 is an enlarged left perspective view of the area of ​​detail indicated in FIG. 1, and which is another improved view of the end actuation assembly;

-Fig. 8 is an enlarged right side view of the area of ​​detail indicated in FIG. 3, with a pair of end actuation assembly cam grooves shown in broken lines;

-Fig. 9 is a slightly enlarged cross section of the forceps of FIG. 3, showing the internal working components of the housing;

-Fig. 10 is an enlarged cross section of the area of ​​detail indicated in FIG. 9, showing the initial position of a blade assembly disposed within the end actuation assembly;

-Fig. 11 is an enlarged left perspective view, showing the housing without a cover plate, and the internal working components of the forceps disposed therein;

ES 2 348 664 T3

- 8 -fig. 12 is an exploded perspective view of the end actuation assembly, blade assembly, and shaft;

-Fig. 13 is an exploded perspective view of the housing and internal working components thereof, with the attachment of the shaft and end actuation assembly to the housing shown in broken lines;

-Fig. 14 is a greatly enlarged top perspective view of the end actuation assembly, with parts separated, showing a path of advancement for an electrical cable through the upper jaw member;

-Fig. 15 is a longitudinal cross section of the area of ​​detail indicated in FIG. 9;

-Fig. 16 is an enlarged top perspective view of the end actuation assembly, showing the path of advancement of the electrical cable through the opposing jaw members, and the proximal attachment of the blade assembly to a blade tube of reciprocating longitudinally, arranged inside the shaft;

-Fig. 17 is an enlarged top perspective view of the end actuation assembly showing the path of advancement of the electrical cable along a longitudinally disposed channel defined within the outer periphery of the shaft;

-Fig. 18A is a greatly enlarged perspective side view of the housing without the cover plate, showing the path of advancement of the electrical cable through a swivel assembly adjacent a distal end of the housing;

-Fig. 18B is a greatly enlarged perspective side view of the housing without the cover plate, showing the path of advancement of the electrical cable through a swivel assembly, with the shaft mounted within the housing;

-Fig. 19 is a greatly enlarged rear view of the swivel assembly showing an internally disposed stop member;

-Fig. 20 is a perspective view of the forceps of the present specification, shown in a position to grasp and seal a tubular vessel or mallet through a cannula;

-Fig. 21 is a slightly enlarged cross-section of the internal cooperative movements of the four-bar grip assembly disposed within the housing, which effect movement of the jaw members relative to each other;

-Fig. 22 is a greatly enlarged cross section showing the initial movement of an elongated pin upon activation of the four bar grip assembly, shown in broken lines;

-Fig. 23 is a greatly enlarged side view showing the movement of

ES 2 348 664 T3

- 9 compression resulting from a helical spring in reaction to the movement of the four-bar handle assembly;

-Fig. 24 is a greatly enlarged side view showing proximal movement of a cam mode drive pin of the end actuation assembly as a result of proximal compression of the coil spring of FIG. 23, which in turn moves the opposing jaw members into the closed configuration;

-Fig. 25 is a greatly enlarged cross section showing the blade assembly balanced for activation within a cannula;

-Fig. 26 is a top perspective view showing the opposing jaw members in a closed configuration, with a tubular vessel compressed between them;

-Fig. 27 is an enlarged perspective view of a sealed site of a tubular vessel showing a cut line BB for dividing said tubular vessel after sealing;

-Fig. 28 is a longitudinal cross section of the plugged site, taken along line 28-28 of FIG. 27;

-Fig. 29 is a side view of the housing without the cover plate, showing the longitudinal reciprocating movement of the blade tube, upon activation of the activation assembly;

-Fig. 30 is a greatly enlarged cross-section of the distal end of the instrument, showing reciprocating longitudinal movement of the blade assembly, upon activation of the activation assembly;

-Fig. 31 is a longitudinal cross section of the tubular vessel, after reciprocating movement of the blade assembly through the seal site and along the preferred cut line BB of FIG. 28; Y

-Fig. 32 is a greatly enlarged side view, showing the movement of the elongated pin as the movement of the handle assembly restarts along a predefined exit path, which in turn opens the opposing jaw members and releases the tubular vessel. .

DETAILED DESCRIPTION

Referring now to Figs. 1 through 6, shown bipolar forceps or forceps 10 for use in various surgical procedures, generally including a housing 20, a handle assembly 30, a turning assembly 80, an actuating assembly 70, and a end actuation assembly 100, cooperating with each other to grasp, seal, and divide tubular vessels and vascular tissue 420 (FIG. 20). Although most of

ES 2 348 664 T3

The drawings show a bipolar forceps 19 for use in connection with endoscopic surgical procedures, an open forceps 10 'for use in connection with traditional surgical procedures is also contemplated, and which is shown as an example in FIG. 1A. For present purposes, the endoscopic version is set forth in detail, although it is nevertheless contemplated that the open forceps 10 'also include the same or similar operating components and features discussed below.

More particularly, forceps 10 includes a shaft 12 having a distal end 14 dimensioned to mechanically engage end actuation assembly 100, and a proximal end 16 that mechanically engages housing 20. Preferably, shaft 12 is bifurcated at its distal end 14, to form ends 14a and 14b that are dimensioned to receive end actuation assembly 100, as best seen in FIGS. 7 and 12. Proximal end 16 of shaft 12 includes notches 17a (see Figures 23 and 29) and 17b (see Figures 11, 12, and 13), sized to mechanically engage corresponding retainers 83a (Figure 18A) and 83b (FIG. 13, shown in dotted lines) of turning assembly 80, as described in detail below. In the drawings and in the description that follows, the term proximal refers, as is traditional, to the end of the forceps closest to the user, and the term distal refers to the end furthest from the user.

As best seen in fig. 1A, forceps 10 also includes an electrical interface or plug 300, which connects said forceps 10 to an electrosurgical power source, eg, a generator (not shown). Plug 300 includes a pair of pin members 302a and 302b, sized for mechanical and electrical connection of forceps 10 to the electrosurgical power source. An electrical cord 310 extends from plug 300 to sleeve 99, which securely connects cord 310 to forceps 10. As best seen in FIGS. 9, 11, and 18A, cable 310 is internally divided into conductors 310a and 310b, each of which transmits electrosurgical energy through their respective forward paths from forceps 10 to end actuation assembly 100, as shown. explains in detail later.

The handle assembly 30 includes a fixed handle 50 and a movable handle 40. The fixed handle 50 is integrally associated with the housing 20, and the handle 40 is movable with respect to the fixed handle 50, as explained in detail below with respect to to the operation of the forceps 10. The turning assembly 80 is preferably attached to a distal end 303 (FIG. 18A) of housing 20, and is rotatable approximately 180 degrees in any direction about a longitudinal axis A.

ES 2 348 664 T3

- 11 As best seen in figs. 2 and 13, housing 20 is formed of two halves 20a and 20b thereof, each of which includes a plurality of contact surfaces 307a, 307b, and 307c (FIG. 13) dimensioned to mechanically align and engage with each other and forming the housing 20, which encloses the interior working components of the forceps 10 therein. As can be seen, the fixed handle 50, which as mentioned above is integrally associated with the housing 20, assumes its shape when mounting the housing halves 20a and 20b.

It is envisaged that a plurality of additional contact surfaces (not shown) may be arranged at various points around the periphery of housing halves 20a and 20b, for ultrasonic welding purposes, eg, energy directing / deflection points. It is also contemplated that the housing halves 20a and 20b (as well as the other components described below) may be assembled together in any other way known in the art. For example, alignment pins, quick-fit or tongue-and-groove contact surfaces, locking tabs, adhesive openings, etc., can be used alone or in combination, for mounting purposes.

Similarly, pivot assembly 80 includes two halves 80a and 80b which when assembled cover and engage proximal end 16 of shaft 12, to allow selective rotation of end actuation assembly 100, as needed. Half 80a includes a pair of retainers 89a (FIG. 13) sized to engage a corresponding pair of receptacles 89b (shown in dashes in FIG. 13) disposed in half 80b. Movable handle 40 and actuation assembly 70 are preferably of unitary construction, and are operatively connected to housing 20 and fixed handle 50 during the assembly procedure.

As noted above, end actuation assembly 100 is attached to distal end 14 of shaft 12, and includes a pair of opposing jaw members 110 and 120. The movable handle 40 of the handle assembly 30 is finally connected to a drive rod 32, which together mechanically cooperate to impart movement to the jaw members 110 and 120 from an open position, wherein said jaw members 110 and 120 they are arranged in spaced relationship to one another, to a closed or clamping position, in which said jaw members 110 and 120 cooperate to grip tissue 420 (FIG. 20) between them. This is explained in detail below with reference to Figs. 9 to 11 and 20 to 29.

It is envisaged that the forceps 10 may be designed so that it is totally or partially disposable, depending on the particular purpose or to achieve a

ES 2 348 664 T3

- 12 particular result. For example, end actuation assembly 100 may be selectively and releasably engageable to distal end 14 of shaft 12, and / or proximal end 16 of shaft 12 may be selectively and releasably engageable to housing 20 and the handle assembly 30. In either of these two cases, the forceps 10 can be considered partially disposable or replaceable, that is, a new or different end actuation assembly 100 (or an end actuation assembly 100 and a shaft 12) selectively replace said end. old set 100, as needed).

Turning now to the most significant features of the present specification, as described with respect to Figs. 1A through 13, movable handle 40 includes an opening 42 defined therethrough, which allows a user to grasp and move said handle 40 relative to fixed handle 50. Handle 40 also includes an ergonomically enhanced grip element 45, disposed along the inner peripheral edge of opening 42, which is designed to make it easier to grip movable grip 40 during activation. It is envisaged that the grip 45 may include one or more protrusions, recesses, and / or ridges 43a, 43b, 43c, respectively, to facilitate grip 40. As best seen in FIG. 11, the movable handle 40 is selectively movable about a pivot 69, from a first position relative to the fixed handle 50 to a second position in immediate proximity to said fixed handle 50, which as explained below imparts movement between yes of jaw members 110 and 120. As best shown in FIG. 11, the housing 20 encloses a drive assembly 21 that cooperates with the movable handle 40, to impart movement to the jaw members 110 and 120, from an open position in which said members 110 and 120 are disposed in spaced relationship between yes, to a clamping or closed position in which said jaw members 110 and 120 cooperate to grip tissue between them. The handle assembly 30 can be generally characterized as a four-bar mechanical joint, composed of the following elements: the movable handle 40, a link 65, a cam-like link 36, and a base link embodied by the fixed handle 50, and a pair of pivot points 37 and 67b. Movement of handle 40 activates the four-bar linkage, which in turn actuates drive assembly 21 to impart movement of opposing jaw members 110 and 120 to grip tissue between them. It is envisioned that the use of the four-bar mechanical linkage will allow the user to gain significant mechanical advantage when jaw members 110 and 120 are compressed against tissue 320, as explained in detail below with respect to

ES 2 348 664 T3

- 13 the operating parameters of the drive assembly 21. Although shown as a four-bar mechanical joint, the present specification contemplates other joints to effect relative movement of the jaw members 110 and 120, as is known in the art. .

Preferably, fixed handle 50 includes a channel 54 defined therein that is dimensioned to receive an elongated spike 92 extending proximally from movable handle 40. Preferably, said elongated spike 92 includes an end 90 fixed to movable handle 40, and a free end 93 in the shape of a T sized to facilitate its reception within the channel 54 of the handle 50. It is envisaged that the elongated pin 92 may be dimensioned to allow the user to move the jaw members 110 and 120 relative to each other progressively and / or incrementally, from the open to the closed position. For example, it is also contemplated that elongated shank 92 may include a ratchet-like contact surface that lockably engages movable grip 40, and thus that jaw members 110 and 120 are positioned in incrementally selective positions relative to one another. , depending on a particular purpose.

Other mechanisms may also be employed to control and / or limit the movement of handle 40 relative to handle 50 (and jaw members 110 and 120), such as, for example, hydraulic, semi-hydraulic, and linear actuators, and gas assisted mechanisms and / or gear systems.

As best illustrated in FIG. 11, housing halves 20a and 20b, when assembled, form an interior cavity 52 that predefines channel 54 within fixed grip 50, so that an entry path 53 and exit path 58 are formed for movement alternative of the end 93 of the elongated pin 92 in said channel. Once assembled, two generally triangular shaped members 57a and 57b are positioned in close abutting relationship with each other to define a rail or track 59 between them. During the movement of the elongated pin 92 along the entry and exit paths 53 and 58, respectively, the T-shaped end 93 runs along the track 59 between the two triangular members 57a and 57b, of in accordance with the particular dimensions of the triangular shaped members 57a and 57b, which as can be appreciated predetermine part of the general pivotal movement of the handle 40 with respect to the fixed handle 50.

Once actuated, handle 40 moves in a generally arcuate fashion toward fixed handle 50 about pivot 69, causing link 65 to rotate proximally about pivots 67a and 67b, which in turn causes the link

ES 2 348 664 T3

- 14 36 cam-like rotate about pivots 37 and 69 in a generally proximal direction. The movement of the cam-like link 36 imparts the movement to the drive assembly 21, as explained in detail below. In addition, proximal rotation of link 65 about pivots 67a and 67b also causes a distal end 63 of link 65 to release, ie unlock, actuation assembly 70, for selective actuation. This feature is explained in detail with reference to Figs. 21 to 29, as well as the operation of the blade assembly 200.

Turning now to fig. 12, an exploded view of shaft 12 and end actuation assembly 100 is shown. As noted above, shaft 12 includes distal and proximal ends 14 and 16, respectively. Distal end 14 is bifurcated and includes ends 14a and 14b, which together define a cavity 18 for receiving end actuation assembly 100. Proximal end 16 includes a pair of notches 17a (fig. 29) and 17b (fig. 11), which are sized to engage the corresponding retainers 83a and 83b (fig. 13) of the rotation assembly 80. As can be seen, the actuation of the rotation assembly 80 rotates the shaft 12, which in turn rotates the rotation assembly actuation 100 of the end to manipulate and grasp the tissue 420.

The shaft 12 also includes a pair of longitudinally oriented channels 19a (fig. 15) and 19b (fig. 12), each dimensioned to carry a conductor 310a and 310b, respectively, of the electrosurgical cable, for final connection to each jaw member 120 and 110, respectively, as explained in detail below with reference to FIGS. 14 to 17. Shaft 12 also includes a pair of longitudinally oriented grooves 197a and 197b, disposed at ends 14a and 14b, respectively. The grooves 197a and 197b are preferably dimensioned to allow longitudinal reciprocation therein of a cam pin 170, as explained below with reference to FIGS. 23 and 24, which causes movement of the opposing jaw members 110 and 120 from the open to the closed position.

Shaft 12 also includes a pair of sockets 169a and 169b, disposed at distal ends 14a and 14b, that are dimensioned to receive a corresponding pivot pin 160. As explained below, said pivot pin 160 fixes jaws 110 and 120 to shaft 12 between bifurcated distal ends 14a and 14b, and mounts said jaw members 110 and 120 so that longitudinal reciprocating movement of cam pin 170 rotate jaw members 110 and 120 about pivot pin 160 from open to closed position.

The shaft 12 is preferably dimensioned to slidably receive therein a blade tube 34 to which the blade assembly 200 is coupled, so that the movement

The longitudinal movement of the blade tube 34 actuates the blade assembly 200 to divide the tissue, as explained below with respect to FIGS. 29 to 31. Blade tube 34 includes a flange 35 located at its proximal end, and a pair of opposing notches 230a and 230b (Figs. 25 and 30) located at a distal end 229 thereof. As best seen in fig. 13, flange 35 is dimensioned to engage corresponding sleeve 78 disposed at a distal end of actuation assembly 70, such that distal movement of sleeve 78 displaces blade tube 34, which in turn actuates blade assembly 200 . A plug 193 may be mounted on top of blade tube 34 and located between said tube 34 and shaft 12. It is envisaged that the obturator 193 may be sized to facilitate reciprocating the blade tube 34 within the shaft 12, and / or protect the other more sensitive interior operating components of the forceps, against undesirable flooding of fluid during surgery. The obturator 193 can also be used to control / regulate pneumoperitoneal pressure leaks through the forceps 10 during surgery. Said plug 193 preferably includes a pair of opposed bearings 195a and 195b, which ensure smooth and precise reciprocating movement of blade tube 34 within shaft 12 (see FIG. 16).

Notches 230a and 230b are preferably dimensioned to engage the key-like intermediate surface 211 of blade assembly 200, which includes a pair of opposing retainers 212a and 212b and a pair of opposing steps 214a and 214b. As best illustrated in Figs. 25 and 30, each retainer and step arrangement, eg, 212a and 214a, respectively, securely engages the corresponding notch, eg, 230a, so that the distal end of step 214a abuts the distal end 229 of the tube. 34 blade. Engagement of the blade tube 34 to the blade assembly 200 in this manner is intended to ensure a smooth and precise movement of the blade tube 34 through the tissue 420.

As can be appreciated in the present specification, the blade tube 34 and the blade assembly 200 are preferably mounted to act independently of the operation of the drive assembly 21. However, as described in detail below, the blade assembly 200 is dependent on the actuator assembly 21 for activation, that is, the activation / movement of the actuator assembly 21 (via the handle assembly 30 and of its internal working components) unlocks the blade assembly 200 for selective tissue separation. For present purposes, drive assembly 21 consists of drive rod 32 and compression mechanism 24, which includes a certain

ES 2 348 664 T3

- 16 number of cooperative elements, which are described below with reference to fig. 13. It is envisaged that the arrangement of the drive assembly 21 in this manner allows for easy and selective engagement of the drive rod 32 within the compression mechanism 24 for mounting purposes.

Although the drawings show a disposable version of the forceps 10 described herein, it is contemplated that the housing 20 may include a release mechanism (not shown) that allows selective replacement of the actuator rod 32 for disposal purposes. Thus, the forceps will be considered partially disposable or replaceable, that is, the shaft 12, the end actuation assembly 100, and the blade assembly 200 are disposable and / or replaceable, while the housing 20 and the assembly handle 30 are reusable.

As best illustrated in Figs. 16 and 17, drive rod 32 includes a pair of chamfered or beveled edges 31a and 31b at a distal end thereof, preferably sized to allow easy reciprocating movement of said drive rod 32 through a blade carrier or guide. 220 which is part of the blade assembly 200. A pin slot 39 is disposed in the distal tip of drive rod 32, and is dimensioned to accommodate cam pin 170, so that reciprocating longitudinal movement of drive rod 32 within blade tube 34 translates the cam pin 170, which in turn rotates jaw members 110 and 120 about pivot pin 160. As explained in detail below with respect to FIGS. 2. 3 and 24, the cam pin 170 mounts within the slots 172 and 174 of the jaw members 110 and 120, respectively, causing said jaw members 110 and 120 to rotate from the closed to the open position, around the fabric 420.

The proximal end of drive rod 32 includes a tab 33 that is preferably sized to engage a corresponding compression sleeve 28 disposed within compression mechanism 24. Proximal movement of sleeve 28 (as discussed below with respect to figs. twenty-one through 24) alternately displaces (ie, pulls on) drive rod 32, which in turn pivots jaw members 110 and 120 from open to closed position. Actuator rod 32 also includes a donut-like spacer 95, which is dimensioned to maintain pneumoperitoneal pressure during endoscopic procedures. It is also envisaged that the O-ring 95 can also prevent flooding by surgical fluids, which can be detrimental to the internal operating components of the forceps 10. The O-ring 95 is also made of

ES 2 348 664 T3

17 a material having a low coefficient of friction, to facilitate the uniform and precise reciprocating movement of the actuating rod 32 within the blade tube 34.

As noted above, blade assembly 200 is disposed between opposing jaw members 110 and 120 of end actuation assembly 100. Preferably, blade assembly 200 and end actuation assembly 100 are independently operable, that is, actuation assembly 70 actuates blade assembly 200, and handle assembly 30 actuates said end actuation assembly 100. The blade assembly 200 includes a bifurcated blade bar or rod 210, having two forks 210a and 210b and a blade carrier or guide 220. Blade forks 210a and 210b include the key-like intermediate faces 211 described above (comprised of steps 214a, 214b and retainers 212a, 212b, respectively) disposed at their proximal end for engagement with blade tube 34 (as shown described), and a common distal end 206 carrying a blade 205 therein to cut tissue 420. Preferably, each yoke 210a and 210b includes a taper 213a and 213b, respectively, that converge to form a common distal end 206. Tapers 213a and 213b are intended to facilitate reciprocating movement of blade 205 through actuation assembly 100 of the end, as described in detail below and best illustrated in FIG. 30.

Each fork 210a and 210b also includes a raised and tapered portion 221a and 221b disposed along its outer periphery, which is dimensioned to engage the corresponding slot 223a and 223b, respectively, disposed in the blade holder or guide 220 ( see fig. 16). It is envisioned that this arrangement of raised portions 221a, 221b, and grooves 223a, 223b, may be designed to restrict and / or regulate the general distal movement of blade 206 after activation. Each yoke 210a and 210b also includes arcuately shaped notches 215a and 215b, respectively disposed along its inner edge and sized to facilitate insertion of a roller or bushing 216 disposed between jaw members 110 and 120 during assembly.

As previously stated, blade assembly 200 includes a blade holder or guide 220, which in turn includes opposing spring tabs 222a and 222b at its proximal end, and upper and lower guides 224a and 224b, respectively. , at its distal end. The inward facing surface of each spring tab, eg 222b, is preferably sized to effect mating engagement with a corresponding chamfered edge, eg 31b of the rod.

ES 2 348 664 T3

- 18 drive 32 (FIG. 16), and the outwardly facing surface is preferably sized for friction fit engagement with the inner periphery of shaft 12. As best seen in FIG. 12, the blade carrier 220 also includes a drive rod channel 225 defined therethrough, sized to allow reciprocating movement of said drive rod 32 during the opening and closing of the jaw members 110 and 120. Blade guide 220 also includes supports 226a and 226b extending laterally therefrom and abutting proximal ends 132, 134 of jaw members 110 and 120 when disposed in the closed position.

Blade guides 224a and 224b preferably include grooves 223 a and 223b, respectively, that guide blade forks 210a and 210b along them during activation to provide smooth and accurate travel of blade 205 through tissue. 420. The grooves 223a and 223b are intended to also prevent unwanted lateral movements of the blade assembly 200 during activation. Preferably, the blade holder 220 is located at a point slightly beyond the shoulder portions 221a and 221b in mounting.

Blade assembly 200 also includes a roller or bushing 216 that is dimensioned to mate with the inner peripheral edge of each fork 210a and 210b, so that during activation, forks 210a and 210b slide over roller or bushing 216 to ensuring easy and accurate reciprocating movement of blade assembly 200 through tissue 420. Bushing 216 is also dimensioned to seat between opposing jaw members 110 and 120, and is preferably held between them by pivot pin 160. As noted above, arcuate-shaped notches 215a and 215b facilitate insertion of the bushing. 216 during assembly.

End actuation assembly 100 includes opposing jaw members 110 and 120, seated within cavity 18 defined between forked ends 14a and 14b of shaft 12. Jaw members 110 and 120 are generally symmetrical and include characteristic components. The like cooperating to allow easy rotation about pivot pin 160 to effect sealing and division of tissue 420. As a result, and unless otherwise stated, only the jaw member 110 and the operating features associated with it are described in detail, although as can be appreciated, many of these features apply to the jaw member 120 as well.

More particularly, the jaw member 110 includes a pivoting shoulder 16 having an arcuately shaped interior surface 167, which is dimensioned to

ES 2 348 664 T3

- 19 allowing said jaw member 110 to rotate around bush 216 and pivot pin 160 upon reciprocating movement of drive rod 32, as previously described. Pivot shoulder 16 also includes a cam slot 172 dimensioned to engage cam pin 170, so that longitudinal movement of drive rod 32 causes cam pin 170 to move along the cam slot. 172. It is envisaged that the cam slot 172 may be dimensioned to allow different turning paths, depending on a particular purpose or to achieve a particular result. For example, US patent pending and of the same assignee as this, no. US 6,511,480, describes a two-stage cam slot arrangement, which as can be appreciated provides a unique pivot path for the jaw members around the pivot point.

Pivot boss 166 also includes a recess 165 preferably sized to clamp a free end of bushing 216 between jaw members 110 and 120. The inner periphery of recess 165 is preferably sized to receive pivot pin 160 therethrough, to clamping jaw member 110 to shaft 12. Jaw member 120 includes a similar recess 175 (FIG. 14) that secures the opposite end of bushing 216 and jaw member 120 to shaft 12.

Jaw member 110 also includes a jaw housing 116, an insulator or insulating substrate 114, and an electrically conductive surface 112. Jaw housing 116 includes a slot (not shown, see slot 179 in jaw member 120) defined therein and sized to engage a ridge-like intermediate surface 161 disposed along the outer periphery of insulator 114. The insulator 114 is preferably sized to securely engage the electrically conductive sealing surface 112. This can be accomplished by stamping, overmolding, overmolding an electrically conductive stamped sealing plate, and / or overmolding an injection molded metal sealing plate. All of these manufacturing techniques produce an electrode having an electrically conductive surface 112 substantially surrounded by an insulating substrate 114. The insulator 114, the electrically conductive sealing surface 112, and the non-conductive outer jaw housing 116 are preferably sized to limit and / or reduce many of the known undesirable effects related to tissue sealing, for example, flashovers in arc, thermal expansion, and eddy current dissipation.

Preferably, the electrically conductive sealing surface 112 may also include a snap fit 119 (FIG. 25) that facilitates tight engagement of

ES 2 348 664 T3

- 20 the electrically conductive surface 112 to the insulating substrate 114, and also simplifies the general manufacturing process. It is envisaged that the electrically conductive sealing surface 112 may also include an outer peripheral edge having a certain radius, and the insulator 114 is attached to the electrically conductive sealing surface 112 along a bonding edge that is generally tangential to the radius, and / or joins along said radius. Preferably, on the intermediate face, electrically conductive surface 112 is raised relative to insulator 114.

Isolator 114 also includes an inward leg 162, which abuts pivot boss 166 and is designed to restrict / reduce expansion of proximal tissue, and / or isolate electrically conductive sealing surface 112 from the remainder of actuation assembly 100. from the end during activation. Preferably, electrically conductive surface 112 and isolator 114 form a channel 168a, 168b defined therebetween and longitudinally oriented, when mounted, for reciprocating movement of knife blade 205. More particularly, and as best illustrated in FIG. 14, insulator 114 includes a first channel 168b that aligns with a second channel 168a on electrically conductive sealing surface 112, to form the entire blade channel. Said knife channel 168a, 168b is intended to facilitate reciprocating longitudinal movement of knife blade 205 along a preferred cutting plane BB, to effectively and precisely separate tissue 420 along the formed seal. of said tissue (see Figures 27, 28, and 31).

As noted above, jaw member 120 includes similar elements, which in turn include: a pivot shoulder 176 having an arcuate-shaped interior surface 177, a cam slot 174, and a recess 175; a jaw housing 126 including a slot 179 dimensioned to engage a ridge-like intermediate surface 171 disposed along the outer periphery of an insulator 124; isolator 124 including an inwardly facing leg 172 abutting pivot shoulder 176; and an electrically conductive sealing surface 122 sized to securely engage isolator 124. Likewise, electrically conductive surface 122 and isolator 124, when assembled form a longitudinally oriented channel 178a, 178b defined therethrough, for reciprocating displacement. knife blade 205.

Preferably, jaw members 110 and 120 are electrically isolated from each other so that electrosurgical energy can be effectively transferred through tissue 420 to form seal 425. For example and as best illustrated in FIGS. 14 and 15, each jaw member, for example 110, includes a cable

ES 2 348 664 T3

- 21 electrosurgical of a unique design disposed therethrough, which transmits electrosurgical energy to the electrically conductive sealing surfaces 112, 122. More particularly, the jaw member 110 includes a cable guide 181a disposed above the pivot shoulder 16, which directs the cable lead 310a toward an opening 188 disposed through the jaw housing 116. In turn, aperture 188 directs conductor 310a toward electrically conductive sealing surface 112 through a window 182 disposed within an insulator 114. A second cable guide 181b grips conductor 310a along the predefined cable path through window 182, and directs a terminal end 310a 'of conductor 310a into a crimp-type electrical connector 183 disposed on one side. opposite of the electrically conductive sealing surface 112. Preferably, conductor 310a is held loosely but securely retained along the path of the cable, to allow rotation of jaw member 110 about pivot 169.

As can be appreciated, this isolates the electrically conductive sealing surface 112 from the remaining operating components of the end actuation assembly 100 and shaft 12. The jaw member 120 includes a similar cable path disposed therein, and through which it includes a similarly sized cable guides, openings, and electrical connectors not shown in accompanying illustrations.

Figs. 15-17 also show the path of advancement described for both electrosurgical cable conductors 310a and 310b, along the outer periphery of shaft 12 and through each jaw member 110 and 120. More particularly, FIG. 15 shows a cross section of electrosurgical cable conductors 310a and 310b disposed within channels 19a and 19b, respectively, along shaft 12. FIGS. 16 and 17 show the path of advancement of cable conductors 310a and 310b from opposite channels 19a and 19b of shaft 12, through pivot shoulders 166 and 176 of jaw members 110 and 120, respectively. It is contemplated that this single cable advancement path for conductors 310a and 310b, from shaft 12 to jaw members 110 and 120, not only isolates each jaw member 110 and 120, but also allows said members 110 and 120 pivot about pivot pin 160 without undue stress or possible entanglement of cable conductors 310a and 310b. In addition, the snap-on electrical connector 183 (and the corresponding connector on the jaw member 120) is intended to greatly facilitate the fabrication and assembly procedure, and to ensure a uniform and firm electrical connection for the transfer of energy through the tube. fabric 420. As best shown in

ES 2 348 664 T3

- 22 fig. 17, the outer surface of shaft 12 may be covered by a thermal shrink tubing 500 or the like, which protects conductors 310a and 310b from undue wear or breakage, and secures said conductors within their respective channels 19a and 19b.

Figs. 18a and 18b show the path of advancement of leads 310a and 310b through turning assembly 80, which again allows the user added flexibility during use of forceps 10, due to the uniqueness of said path of advancement. More particularly, fig. 18a shows the path of advancement of conductor 310a through half 80a of turning assembly 80, and FIG. 18B shows the path of leads 310a and 310b as they advance through instrument housing 20a, through half 80a of turning assembly 80, and into channels 19a and 19b of shaft 12. FIG. 18A shows only the path of advancement of lead 310a through half 80a of turning assembly 80, but it can nevertheless be appreciated that lead 310b (shown in dashes in FIG. 19) is similarly located within the half. 80b of the turning assembly 80.

As best illustrated in FIG. 18A, conductors 310a and 310b are provided to be advanced through respective halves 80a and 80b of turning assembly 80 in such a way as to allow turning of shaft 12 (via turning of turning assembly 80) at direction of rotation to the right or to the left, without the leads 310a and 310b becoming unduly tangled or twisted. More particularly, each conductor, eg 310a, loops through each half 80a of turning assembly 80 to form slack loops 321a and 321b that intersect on either side of longitudinal axis A. Slack loop 321a redirect lead 310a through one side of axis A, and slack loop 321b returns lead 310a through axis A. Advancing conductors 310a and 310b in this manner through turning assembly 80 is intended to allow the user to turn shaft 12 and end actuation assembly 100, without undue tension or entanglement of conductors 310a and 310b, thereby which can be detrimental to an effective seal. Preferably, the loop-like cable advancement paths allow the user to rotate the end actuation assembly 100 approximately 180 degrees in either direction, without tensioning the conductors 310a and 310b. This path of advancement of the cable conductors described herein is intended to rotate said conductors 310a and 310b approximately 178 degrees in either direction.

Fig. 19 is an interior view of the half 80a of the turning assembly 80 along the axis A, to observe in detail its internal characteristics. More particularly, at least one stop 88 is preferably located within each rotary half 80a and 80b, which acts to control the overall rotational movement of the rotary assembly 80.

- 23 ximately 180 degrees in any direction. The stop member 88 is dimensioned to contact a corresponding notch 309c disposed along the periphery of the outer flange 309, to prevent undue over-turning of the turning assembly 80, which could unduly stress one or both conductors 310a and 310b of the cable.

Fig. 18b shows the path of advancement of electrical cable conductors 310a and 310b from housing 20a, through turning assembly 80 and to shaft 12. It is provided that conductors 310a and 310b are routed through each part of the forceps 10 by means of a series of cable guide members 311a to 311g disposed at various positions through housing 20 and turning assembly 80. As explained below, a series of mechanical intermediate surfaces, for example, 309a, 309b (fig. 13) and 323a, 323b (fig. 13) may also be dimensioned to help guide cables 310a and 310b through the cable. housing 20 and swivel assembly 80.

Returning to fig. 13, showing the exploded view of housing 20, pivot assembly 80, actuation assembly 70, and handle assembly 30, all of these various component parts, along with shaft 12 and end actuation assembly 110, are intended to be assembled during the manufacturing process to form a partially and / or fully disposable forceps 20. For example, and as noted above, shaft 12 and / or end actuation assembly 100 may be disposable, and therefore selectively or releasably coupled to housing 20 and twist assembly 80, to form a forceps. 10 partially disposable, and / or all of said forceps 10 may be disposable after use.

Housing 20 is preferably formed of two halves 20a and 20b, which are engaged together by a series of intermediate mechanical contact surfaces 307a, 307b, 307c, and 308a, 308b, 308c, respectively, to form an interior cavity 300 to accommodate the interior working components of forceps 10 that have been described. For present purposes, housing halves 20a and 20b are generally symmetrical, and unless otherwise noted, a component described with respect to half 20a will have a similar component that forms part of housing half 20b.

Housing half 20a includes proximal and distal ends 301a and 301b, respectively. Proximal end 301a is preferably sized to receive an electrical sleeve 99 that secures electrosurgical lead 310 (FIG. 1) within said housing 20. As best seen in FIGS. 9 and 21, the paired cable 310 is divided into two conductors 310a and 319b of the electrosurgical cable, which are advanced

ES 2 348 664 T3

- 24 subsequently through housing 20 to ultimately transmit different electrical potentials to opposing jaw members 110 and 120. As noted above, various cable guides 311a to 311g are located throughout the entire housing 20 and assembly of rotation 80, to direct cable conductors 310a and 310b towards channels 19a and 19b arranged along the outer periphery of shaft 12.

Distal end 303a is generally arcuate in shape so that when assembled, distal ends 303a and 303b form a collar 303 (FIG. 13) that extends distally from housing 20. Each distal end 303a, 303b of collar 303 includes an outer flange 309a, 309b and a recess 323a, 323b, which cooperate to engage corresponding mechanical projections 84a, 84b (FIG. 29) and flanges 87a, 87b, respectively, disposed within turning assembly 80. As can be appreciated, the interlocking couplings of flanges 309a, 309b with shoulders 84a, 84b, and of recesses 323a, 323b with flanges 87a, 87b, are sized to allow free rotation around rotation assembly 80 and of collar 303 once assembled. As already stated, the stop member or members 88 and the notch or notches mechanically cooperate to limit the rotational movement of the rotary assembly 80, to prevent the cable conductors 310a and 310b from being stressed.

Each distal end 303a, 303b of collar 303 also includes an interior cavity 317a and 317b (Figs. 9 and 21), respectively, defined therein, which allows free rotation of shaft 12, blade tube 34, and conductors. 310a and 310b of the cable housed in it. A plurality of retainers 89a located within pivot assembly 80 engage a corresponding plurality of receptacles 89b (FIG. 13) disposed within rotary half 80b, to balance rotary assembly 80 in rotational relationship on top of collar 303.

Housing half 20a also includes a plurality of hub-like pivot assemblies 329a, 331a, and 333a, which as explained in detail below with respect to instrument operation, cooperate with opposing hub-like pivot assemblies. (shown in dashes in fig. 13) arranged in the housing half 20b, for coupling to the free ends of the pivot pins 37, 67b, and 77, respectively, which are associated with the different operating components described below. Preferably, each of these assemblies 329a, 331a, and 333a provides a fixed pivot point for each pivot element, ie, cam link 36, handle link 65, and actuator assembly 70, respectively.

As best seen in Figs. 11 and 13, the fixed handle 50, which is in the shape of the housing assembly 20, includes an outer surface 51 as a

ES 2 348 664 T3

- 25 shell and an internal cavity 52 defined therein. As previously stated with respect to the discussion of FIG. 11, these elements and the other internal elements of the fixed grip 50 cooperate with the movable grip 40 to activate the four-bar mechanical linkage, which in turn actuates the drive assembly 21 to impart movement to each other to the opposing jaw members. 110 and 120 to grip fabric 420 between them.

The handle assembly 30 including the aforementioned fixed handle 50 and movable handle 40 includes the cam link 36 which is generally triangular in shape. Said cam link includes an upper piston 38, a fixed pivot 37, and a handle pivot 69. The cam link is mounted within the interior cavity 300 of the housing 20, between the halves 20a and 20b thereof. More particularly, fixed pivot 37 is rotatably mounted within fixed mounts 329a and 329b, between opposing housing halves 20a and 20b, and handle pivot 69 is rotatably mounted within bifurcated end of handle 40, through openings 68a and 68b. Cam piston 38 is balanced within a longitudinal channel 25c defined through drive assembly 70 (explained in detail below with respect to the discussion of drive assembly 70) in abutting relationship with compression tab 25. , so that movement of handle 40 rotates piston 38 proximally against coil spring 22. These and other details relating to the operational characteristics are set forth below with reference to Figs. 21 to 29.

Link 65 is also associated with handle assembly 30, and forms an integral part of the four-bar mechanical linkage. Said link 65 includes a distal end 63 and two pivot pins 67a and 67b. Pivot pin 67a engages openings 68a and 68b within movable handle 40, and pivot 67b engages fixed mounts 331a and 331b between housing halves 20a and 20b, so that movement of the handle 40 toward fixed handle 50 pivots link (about pivots 67a and 67b. As explained in detail below, distal end 63 acts as a lock for actuation assembly 70.

Movable handle 40 includes an elongated spike 92 that is preferably mounted to movable handle 40 by pins 46a and 46b, which engage openings 41a and 41b disposed within handle 40 and openings 91a and 91b arranged in spike. mobile 92, respectively. Other coupling methods are also contemplated, such as snap-in, snap tab, etc. Elongated spike 92 also includes a T-shaped distal end 93, which as before

ES 2 348 664 T3

- 26 said with respect to fig. 11, it travels within a predefined channel 54 disposed within the fixed handle 50. Additional features with respect to the T-shaped end 93 are set forth below in the detailed description of the operating features of the forceps 10.

A drive assembly 21 is preferably located within housing 20, between halves 20a and 20b thereof. As discussed above, said drive assembly 21 includes the above-described drive rod 32, and compression mechanism 24. Said compression mechanism 24 includes a compression sleeve 27 that is telescopically and / or slidably arranged within the mount. spring 26. The distal end 28 of the compression sleeve 27 is preferably C-shaped and is dimensioned to engage the tab 32 provided at the proximal end of the actuating rod 32, so that the longitudinal movement of the compression sleeve 27 acts on the rod. drive 32. The proximal end of the compression sleeve 27 is dimensioned to engage a compression tab 25 in the form of a weight lifting bar, disposed within a longitudinal slot 25a of the spring assembly 26. Compression sleeve 27 also includes a longitudinal groove or channel 25c that is longitudinally aligned with groove 25s, and sized to receive cam piston 38 of cam link 36 described above.

The proximal end of spring assembly 26 includes a circular flange 23 that is dimensioned to bias compression spring 22 after compression mechanism 24 is mounted and seated within housing 20 (FIG. 11). The distal end of the spring assembly 26 includes a flange 25f that limits the distal movement of the tab 25 into the slot 25a of the spring assembly 26, and biases the opposite end of the spring 22.

As best seen in fig. 11, once assembled, spring 22 is held for compression on top of a spring mount 26 upon actuation of handle assembly 30. More particularly, movement of cam piston 38 within slot 25c (by movement of lever assembly handle 30) moves the tab over the slot 25s, and alternately displaces the sleeve 25 within the spring assembly, to compress the spring 22. Proximal movement of compression sleeve 27 imparts proximal movement to drive rod 32, which closes jaw members 110 and 120 around tissue 420 (FIG. 28). The compression of spring 22 can be seen through one or more windows 340 arranged in the housing halves, eg, 20b.

ES 2 348 664 T3

- 27 Fig. 13 also shows the activation assembly 70, which activates the blade assembly 200, as previously described with respect to FIG. 12. More particularly, actuator assembly 70 includes actuator 73 having a cuff-like distal end 76 that is dimensioned to receive proximal flange 35 of blade tube 34. An actuator pin 74 extends laterally from the proximal end of actuator 73. Trigger assembly 70 also includes an ergonomically designed trigger 72 having flap-like tabs 72a and 72b to facilitate grasping and firing of the trigger assembly during surgery.

As best seen in fig. 11, the compression sleeve 72 is dimensioned to slide inwardly within the actuator 73 when the forceps is mounted. Likewise, upon actuation the actuator 73 may slide along the outer periphery of the compression sleeve 27, to actuate the blade assembly 200 as previously described with respect to FIG. 12. Drive pin 74 is dimensioned to travel along a pair of guide rails 71a and 71b disposed within a forked tail portion of trigger 72, which includes ends 76a and 76b, respectively.

A hinge or pivot pin 77 mounts trigger 72 between housing halves 20a and 20b, within mounts 333a and 333b. A torsion spring 75 may also be incorporated within actuator assembly 70, to facilitate progressive and smooth longitudinal movement of actuator 73 and blade tube 34 to ensure reliable separation along tissue seal 425 (Figs. 27 and 28). In other words, the activation assembly 70 is configured in a proximal, preload position, prior to said activation. This ensures precise and intentional movement of the blade assembly 200. In addition, the torsion spring 75 preload configuration is intended to act as an automatic recoil of the blade assembly 200, to allow repeated reciprocating through the tissue, as needed. As previously stated, a plurality of gripping elements 71 are preferably incorporated on top of trigger 72 and flap tabs 72a and 72b, to facilitate application of the finger to trigger 72.

Preferably, trigger assembly 70 is initially prevented from firing due to the unique configuration of distal end 63 of link 65, which abuts against trigger 72 and locks trigger assembly 70 prior to actuation of handle assembly 30. In addition, it is provided that the opposing jaw members 110 and 120 can be rotated and partially open and closed without unlocking the activation assembly 70, which as can be appreciated allows the user to grasp and

ES 2 348 664 T3

- 28 manipulating tissue 420 without premature activation of blade assembly 200. As previously discussed, only when the T-shaped end 93 of elongated spike 92 has alternately fully displaced within channel 54 and is seated within a predefined retention gap 62 (as explained below), will the distal end 63 of link (69) will move to the position that will allow action of activation assembly 70.

The operating characteristics and relative movements of the internal working components of forceps 10 are shown with directional lines and arrows, and are best illustrated in FIGS. 21 to 29. As already mentioned, when the forceps 10 is mounted, a predefined channel 54 is formed within the cavity 52 of the fixed handle 50. The channel 54 includes an inlet 53 and an outlet 58, for the alternate displacement of the elongated pin 92 and its T-shaped end 93. Once assembled, the two generally triangular shaped members 57a and 57b are positioned intimately abutting each other, and define track 59 between them.

More particularly, figs. 21 and 22 show initial actuation of handle 40 toward fixed handle 50, causing free end 93 of elongated pin 92 to move generally proximally and upwardly along entry path 53. During the movement of said elongated pin 92 along the entry and exit paths 53 and 58, respectively, the T-shaped end 93 runs along the track 59 between the two triangular members 57a and 57b.

As handle 40 is depressed and elongated pin 92 is engaged in channel 54 of fixed handle 50, cam link 36, thanks to the mechanical advantage of the four-bar linkage, is generally rotated proximally about pivots 37 and 69 so that cam piston 38 pushes tab 25, which compresses spring 22 against flange 23 of the spring assembly (FIG. 23). Simultaneously, drive rod 32 is pulled proximally by compression sleeve 27, which in turn causes cam pin 170 to move proximally within cam grooves 172 and 174 and causes jaw members 110 and 120 close together (fig. 24). It is envisaged that the channel 197 may be dimensioned slightly larger than necessary to account for any dimensional inequalities relative to the manufacturing tolerances of the various operating components of the end actuation assembly 100 (FIG. 24).

The use of a four-bar link is envisioned to allow the user to selectively compress coil spring 22 a specific distance, which in turn imparts a specific load on actuator rod 32. The load on actuator rod 32 is converted to a torque around caliper pivot 160

ES 2 348 664 T3

- 29 via cam pin 170. As a result, a specific closing force can be transmitted to opposing jaw members 110 and 120. It is also contemplated that window 340 provided in housing 20 may include graduations, visual markings. , or other indices, that provide information to the user during compression of the grip assembly 30. As can be appreciated, the user can thus selectively regulate the progressive closing forces applied to the fabric 420, to accomplish particular tasks or results. For example, it is provided that the user can progressively open and close the jaw members 110 and 120 around the tissue, without locking the end 93 of the elongated pin 92 in the retention hole 62. Window 340 may include a specific visual indicator that refers to the most proximal position of end 92, prior to engagement within retention gap 62.

As previously noted, jaw members 110 and 120 can be opened, closed, and rotated to manipulate tissue 420 until sealing is desired, without unlocking activation assembly 70. This allows the user to position and modify the position of forceps 10 prior to activation and obturation. More particularly and as illustrated in fig. 4, the end actuation assembly 100 is rotatable about longitudinal axis A by rotating the rotary assembly 80. As previously stated, the single path of advance of cable conductors 310a and 310b through rotary assembly 80, along shaft 12, and finally through jaw members 110 and 120, has been envisaged, allow the user to rotate the end actuation assembly 100 approximately 180 degrees in both clockwise and counterclockwise directions of rotation, without unduly entangled or tensioned conductors 310a and 310b. As can be appreciated, this facilitates grasping and handling of tissue 420.

A series of abutment members 150a to 150c are preferably employed on the inward facing surfaces of the electrically conductive sealing surfaces 112 and 122, to facilitate grasping and manipulation of the tissue and to define a gap G (FIG. 24) between the gaps. opposing jaw members 110 and 120, during sealing and cutting of tissue.

Once the desired position of the seal location 425 has been determined and the jaw members 110 and 120 properly positioned, the handle 40 can be fully depressed so that the T-shaped end 93 of the elongated pin 92 leaves a free edge. Predefined rail 61, located above the triangular shaped members 57a and 57b. Once the end 93 clears the edge 61, that is, the distal movement of the handle 40 frees the elongated pin 92, it is redirected by the edge 61 to the

ES 2 348 664 T3

- 30 inside the retention space 62 located within the exit path 58. More particularly, as there is a slight reduction in the pressure of the handle 40 against the handle 50, it returns a little distally towards the entrance path 53, but is redirected to exit road 58. At this point, the release of the back pressure between the grips 40 and 50, which is attributable and directly proportional to the release pressure associated with the compression of the actuator assembly 70, causes the end 93 of the elongated pin 92 to seize. clamp or lock within retention gap 62. Handle 40 is now held in place within fixed grip 50, which in turn locks jaw members 110 and 120 to a closed position against tissue 420.

At this point, jaw members 110 and 120 are fully compressed around tissue 420 (FIG. 26). In addition, the forceps 10 is now ready for the selective application of surgical energy and the subsequent separation of tissue 420, that is, by seating the T-shaped end 93 within the locking hole 62, the link (moves to a position that allows activation assembly 70 to be activated (Figs. 21 and 29).

As the T-shaped end 93 of the elongated pin 92 is seated within the retention gap 62, a proportional axial force is maintained on the drive rod 32, which in turn maintains a compressive force between the opposing jaw members. 110 and 120 against 420 fabric. It is envisioned that the end actuation assembly 100 and / or jaw members 110 and 120 may be sized to relieve some of the excessive clamping forces, to avoid hydraulic failure of certain internal operating elements of the end actuator 100.

As can be appreciated, the combination of the mechanical advantage of the four bar link together with the compression force associated with compression spring 22, facilitates and ensures a permanent, uniform, and precise closing pressure around tissue 420.

By controlling the intensity, frequency, and duration of electrosurgical energy applied to tissue 420, the user can cauterize, coagulate / desiccate, plug, and / or simply reduce or retard bleeding. As already stated, two mechanical factors play an important role in determining the resulting thickness of the sealed tissue and the effectiveness of the seal 425, that is, the pressure applied between the opposing jaw members 110 and 120 and the separation distance. G between opposing sealing surfaces 112, 122 of jaw members 110 and 120 during the sealing procedure. However, the thickness of the resulting tissue seal 425 cannot be adequately controlled by force alone. Said in others

ES 2 348 664 T3

At 31 terms, too much force the jaw members 110 and 120 would touch and possibly short, causing little energy to travel through the tissue 420, thus resulting in poor sealing of the tissue. With too little force the seal 425 would become too thick.

Applying the correct force is important for other reasons as well; to join the walls of the glass; to reduce the impedance of the tissue to a value low enough to allow adequate current through the tissue 420; and to overcome the expansive forces during heating of the fabric, in addition to contributing to the creation of the required final thickness of said fabric, which is an indication of a good seal 425.

Preferably, the electrically conductive sealing surfaces 112, 122 of the jaw members 110, 120, respectively, are relatively flat to avoid current concentrations at the sharp edges, and also prevent arcing between high points. In addition, and due to the reaction force of the fabric 420 upon engagement, the jaw members 110 and 120 are preferably manufactured to resist bending. For example, the jaw members 110 and 120 may be tapered along their width, which is advantageous for the following reasons: 1) the taper will apply constant pressure to a tissue of constant thickness in parallel; 2) The thicker proximal portion of jaw members 110 and 120 will resist bending due to the reaction force of tissue 420.

As previously stated, at least one jaw member, for example 110, may include a stop member, for example 150a, that limits the movement of the two opposing jaw members 110 and 120 relative to each other (Figs. 6 and 7). Preferably, the abutment member, eg 150a, extends from the sealing surface 112, 122 a predetermined distance in accordance with the specific properties of the material (eg, compressive strength, thermal expansion, etc.), to provide a uniform and accurate gap distance G during filling (fig. 24). Preferably, the gap distance between opposing sealing surfaces 112 and 122 is within a range of about 0.03mm to about 0.1mm, and more preferably about 0.05mm to about 0.08mm.

Preferably, stop members 150a to 150c are made of insulating material, eg, parylene, nylon, and / or ceramic, and are dimensioned to limit the opposite movement of jaw members 110 and 120 within the aforementioned range of separation. . It is envisaged that the stop members 150a to 150c may be arranged in one or both of the jaw members 110 and 120, depending on the particular purpose to achieve a also particular result. Preferably, the

ES 2 348 664 T3

32 non-conductive stop members 150a to 150c are molded onto the jaw members 110 and 120 (for example, by overmolding, injection molding, etc.), stamped on said jaw members 110 and 120 or deposited (for example, by deposition) on said members 110 and 120. For example, one technique requires thermal spraying of a ceramic material on the surface of jaw member 110 and 120, to form said abutment members 150a to 150c. Various thermal spray techniques are contemplated, which require depositing a wide range of insulating and heat-resistant materials on various surfaces, to create stop members that control the separation distance between electrically conductive surfaces 112, 122. Other techniques for arranging stop members 150a to 150c on electrically conductive surfaces 112 and 122 are also contemplated, for example, by top sliding, snap fit, adhesives, molds, etc.

Furthermore, although it is preferable that the stop members 150a to 150c protrude about 0.03mm to about 0.1mm, and preferably about 0.05mm to about 0.08mm from the inwardly facing surfaces 112, 122 of the jaw members 110 and 120, in some cases it may be preferable to have said stop members 150a to 150c protrude more or less, depending on the particular purpose. For example, it is contemplated that the type of material used for such stop members 150 to 150c, and the ability of the materials to absorb the large compressive closing forces between the jaw members 110 and 120 will vary, and thus the overall dimensions. of said stop members 150a to 150c can vary, as well as produce the desired separation distance G.

In other words, the compression force of the material together with the desired final separation distance G required (desirable to effect sealing, are parameters carefully considered when forming stop members 150a to 150c, and a material may have to be Sized differently than other material, to achieve the same separation distance or the desired result. For example, the compressive strength of nylon is different than that of ceramic, and therefore the nylon material may have to be sized differently, for example thicker, to counteract the clamping force of the jaw members. opposites 110 and 120, and achieve the same desired spacing distance G when using a ceramic stop member.

As best seen in Figs. 27 and 28, as energy is selectively transferred to end actuation assembly 100 through jaw members 110 and 120 and tissue 420, a seal 425 of said tissue is formed that insulates

ES 2 348 664 T3

- 33 two halves 420 and 420b thereof. At this point and with other known vessel sealing instruments, the user must remove and replace the forceps 10 with a cutting instrument (not shown), to divide the tissue halves 420a and 420b along the seal 425. As can be seen, this is time consuming and tedious, and can lead to inaccurate tissue division through the tissue seal 425 due to misalignment or mispositioning of the cutting instrument along the cutting plane. ideal BB of said tissue.

As explained in detail below, the present specification incorporates a blade assembly 200 which when activated via activation assembly 70, progressively and selectively divides tissue 420 along the ideal plane BB in a safe and precise manner. , to effectively and reliably divide tissue 420 into two sealed halves 420a and 420b (FIG. 31), with a tissue gap 430 between them. The reciprocating blade assembly 200 allows the user to quickly separate tissue 420 immediately after obturation, without substituting a cutting instrument through a trocar cannula or opening 410. As can be appreciated, precise sealing and division of tissue 420 is accomplished with the same forceps. It is envisaged that the knife blade 205 may also be coupled to the same or alternative electrosurgical power source, to facilitate separation of tissue 420 along tissue seal 425 (not shown).

Furthermore, it has been envisaged that the angle of the blade tip 207 of the blade 205 thereof can be dimensioned to provide more or less aggressive cutting angles, depending on a particular purpose. For example, the tip 207 of the blade may be positioned at an angle that reduces tissue particles associated with cutting. Furthermore, the tip 207 of the blade can be designed to have different geometries, such as serrated, notched, hollow, concave, convex, etc., depending on the particular purpose or to achieve a also particular result.

Although blade tip 207 is intended to have a relatively sharp leading edge, tip 207 may also be substantially blunt or blunt. More particularly, it is contemplated that the combination of the closing force between the jaw members 110 and 120 as they come together, with the uniquely designed stop members 150a to 150c, hold the tissue firmly between the jaw members 110 and 120, to allow the tissue to be cut by the tip 207 of the blade, even though said tip 207 is substantially blunt. As can be appreciated, a blunt blade tip 207 design eliminates the problems associated with the use of sharp objects in the surgical field.

ES 2 348 664 T3

- 34 Once the tissue is divided into halves 420a and 420b, the jaw members 110 and 120 can be opened by actuating the handle 40 again as explained above. Blade assembly 200 is intended to generally cut progressively and unidirectionally (ie, distally); however, it is contemplated that the knife blade may be sized to cut bi-directionally, also depending on the particular purpose. For example, the force associated with the recoil of the trigger spring 75 can be used with a second blade (not shown) designed to cut loose or sparse bits of tissue upon removal of the blade assembly.

As best seen in fig. 32, resetting or reassembling the handle 40, displaces the T-shaped end 93 of the elongated pin 92 generally proximally along the exit path 58. until the end 93 clears a flange 61 disposed above it. the triangular shaped members 57a, 57b along the exit path 58. Once rim 61 is sufficiently released, grip 40 and elongated tang 92 are fully releasable from grip 50 along exit path 58, by reducing grip / clamping pressure, which in turn returns the jaw members 110 and 120 to the open, pre-activated position.

From the foregoing and with reference to the various figures, those skilled in the art will appreciate that certain modifications may also be made in the present specification, without departing from the scope thereof. For example, it may be preferable to add other features to forceps 10, for example, an articulated assembly to axially displace end actuation assembly 100 relative to elongated shaft 12.

It is also contemplated that the forceps 10 (and / or the electrosurgical generator used in connection with said forceps) may include a sensor or feedback mechanism (not shown), which automatically selects the appropriate amount of electrosurgical energy to effectively seal the tissue. particularly sized gripped between jaw members 110 and 120. The sensor or reporting mechanism may also measure impedance through tissue during sealing, and provide an indication (visual and / or audible) that an effective seal has been created between jaw members 110 and 120.

In addition, it is contemplated that the actuation assembly 70 may include other types of recovery mechanism designed to achieve the same purpose, for example, gas-actuated recovery, electrically actuated recovery (ie, a solenoid) etc. It is also envisaged that the forceps 10 can be used to penetrate or

ES 2 348 664 T3

- 35 cut the fabric without sealing. Alternatively, the blade assembly can be coupled to the same or alternative electrosurgical power source to facilitate cutting of tissue.

Although the figures show forceps 10 manipulating an isolated vessel 420, it is contemplated that such forceps 10 may also be used with non-isolated vessels. Other cutting mechanisms are also considered to cut the fabric 420 along the ideal plane BB thereof. For example, it is envisaged that one of the jaw members may include a cam-actuated blade member, which is seated within one of the jaw members, and upon reciprocation of the cam member is depressed to cut the tissue along a plane substantially perpendicular to the longitudinal axis A.

Alternatively, a shape memory alloy (SMAs) can be used to cut tissue as it transforms from the austenitic state to a martenistic state, with a change in temperature or stress. More particularly, SMAs are a family of alloys that have anthropomorphic qualities of memory and trainability, and are particularly suitable for use in medical instruments. SMAs have been applied to items such as actuators for control systems, steerable catheters, and fasteners. One of the most common SMAs is Nitinol, which can retain shape memories for two different physical configurations, and which changes shape as a function of temperature. Other SMAs based on copper, zinc, and aluminum have recently been developed, which have similar shape memory retention characteristics.

SMAs undergo a crystalline phase transition when variations in temperature and / or stress are applied. A particularly useful attribute of SMAs is that after being deformed by temperature or stress, they can fully regain their original shape when returned to the original temperature. The transformation is known as a thermoelastic martenistic transformation.

Under normal conditions, the thermoelastic martenistic transformation occurs in a temperature range that varies with the composition of the alloy itself and the type of thermomechanical treatment with which it was manufactured. In other words, the temperature at which the shape is memorized by an SMA is a function of the temperature at which the martensitic and austenitic crystals are formed in that particular alloy. For example, Nitinol alloys can be manufactured so that the shape memory effect occurs over a wide temperature range, for example -270 ° C to + 100 ° C.

ES 2 348 664 T3

- 36 Although the jaw members shown and described here are pivotable relative to each other to grip tissue between them, it is intended that the forceps be designed so that said jaw members are mounted in any manner, in which one or both move from a first position juxtaposed with each other to a second position of contact against the tissue.