Cannula for receiving surgical instruments

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to a cannula that accepts a surgical instrument to perform surgery on the body.

【0002】

[Conventional technology]

Endoscopic surgical techniques allow surgery to be performed on a patient's body through a relatively small incision in the body and with less damage to body tissue. Endoscopic surgery typically utilizes a tubular structure known as a cannula that is inserted into a small incision in the body. The cannula keeps the incision open and acts as a conductor tube that extends between the outside of the body and the local area within the body where surgery is performed.

【0003】

[Problems to be Solved by the Invention]

Due to the relatively small size of the passageway into the body formed by the cannula , certain surgical procedures, such as posterior disectomy and surgery using stewable surgical instruments, are internal. It was difficult to do using endoscopic techniques.

【0004】

[Means for solving problems]

The present invention is a cannula that accepts surgical instruments to perform surgery on the body. The cannula is equipped with a tubing structure that defines a passage for inserting surgical instruments into the body. This tubular structure has a proximal end and an distal end. The tubular structure comprises an inflatable portion that allows the cross-sectional area of the passage to be increased, at least at the ends.

【0005】

This inflatable portion of the tubular structure, when inflated, takes the form of a cone. The expandable portion of the tubular structure includes an arcuate slot and a guide pin arranged within the arcuate slot. This guide pin moves from the first end of the slot to the second end of the slot, allowing the cross-sectional area of the passage at the end to increase.

【0006】

The tubing structure comprises first and second tubular portions attached to each other. The second tubular portion has an inflatable portion. The first tubular portion has one stainless steel pipe, and the second tubular portion has an arcuate portion of the stainless steel sheet material wound in a tubular shape.

【0007】

BEST MODE FOR CARRYING OUT THE INVENTION

The above and other features of the invention will be apparent to those skilled in the art of the invention by reference to the following description of the accompanying drawings.

【0008】

The present invention relates to a cannula that accepts a surgical instrument to perform surgery on a patient's body. The present invention is applicable to a wide variety of surgical operations in which endoscopic surgical techniques are used.

【0009】

FIG. 1 illustrates a cannula 10 having a structure according to the present invention. The cannula 10 is a tubular structure 12 whose center is on the axis 14. The tubular structure 12 defines a passage 16 that penetrates the cannula 10. During endoscopic surgery, surgical instruments are inserted into the body through passage 16.

【0010】

The tubular structure 12 includes a first tubular portion 20 and a second tubular portion 40 attached to the first tubular portion. The first tubular portion 20 is preferably made of a single stainless steel pipe, but may be made of another suitable material. The first tubular portion 20 has a proximal end 22 and an distal end 24. The parallel cylindrical inner and outer surfaces 26 and 28 extend between the ends 22 and 24 of the first tubular portion 20, respectively. The inner surface 26 defines the first passage portion 30 of the passage 16 penetrating the cannula 10. The first passage portion 30 has a diameter D1 preferably in the range of 10 mm to 20 mm.

【0011】

The second tubular portion 40 of the tubular structure 12 is attached to the end 24 of the first tubular portion 20. The second tubular portion is preferably made of stainless steel, but may be made of another suitable material.

【0012】

As best shown in the developed view of FIG. 4, the second tubular portion 40 comprises an arcuate portion 42 made of sheet material. The arc-shaped portion 42 includes first and second arc-shaped edge edges 44 and 46, and first and second planar edge edges 48 and 50, respectively. These first and second planar edge edges 48, 50 are rolled in an overlapping manner so that they can form the tubular form of the second tubular portion 40.

【0013】

When the second tubular portion 40 is rolled into its tubular form, the first and second arcuate edges 44, 46 are located opposite the second tubular portion, respectively, the first. And the second ends 60, 62 (Fig. 1 and Fig. 2) are defined. The first end 60 and the second end 62 are connected to each other by a central portion 64. The first end 60 of the second tubular portion 40 is attached to the end 24 of the first tubular portion 20 by a single fastener, such as a rivet 66. The rivet 66 extends through two aligned holes 68 (FIG. 4) in the first end 60 of the second tubular portion 40. The first end 60 of the second tubular portion 40 is rotatable around the rivet 66.

【0014】

The second tubular portion 40 has a parallel inner surface 70 and outer surface 72 (FIGS. 1 and 2) extending between the first end 60 and the second end 62. The inner surface 70 defines a second passage portion 74 of the passage 16 penetrating the cannula 10, which extends as a continuum of the first passage portion 30 of the first tubular portion 20.

【0015】

An arcuate slot 80 is formed in the second tubular portion 40 and extends between the inner surface 70 and the outer surface 72 of the second tubular portion. The arcuate slot 80 extends toward the second end 60 of the second tubular portion along a curved path within the central portion 64 of the second tubular portion 40. The arcuate slot 80 has a first termination 82 located within a central portion 64 of the second tubular portion 40. The second end 84 of the arcuate slot 80 is arranged adjacent to the intersection of the second arcuate edge 46 of the arcuate portion 42 and the first planar edge 48.

【0016】

The guide pin 90 is attached to the inner surface 70 of the second tubular portion 40 adjacent to the intersection of the second arcuate edge 46 and the second planar edge 50. In the tubular form of the second tubular portion 40, the guide pin 90 is located within the arcuate slot 80 and is movable along the curved path of the arcuate slot 80. A washer 92 is fixed to the inner end of the guide pin 90 so that the guide pin can be held in the arcuate slot 80.

【0017】

The second tubular portion 40 of the tubular structure 12 is expandable from the contracted state shown in FIG. 2 to the expanded state shown in FIG. In the contracted state, the guide pin 90 is located within the first termination 82 of the arcuate slot 80 of the second tubular portion 40, and the second passage portion 74 defined by the second tubular portion is cylindrical. It has a shaped shape. The second passage 74 has an overall constant diameter D2 (FIGS. 2 and 3) that is approximately equal to the diameter D1 of the first tubular portion 20. Thus, the cross-sectional area of the second passage portion 74 at the second end 62 of the second tubular portion 40, which is a function of diameter D2, is the break of the first end 60 of the second tubular portion. Approximately equal to the area and approximately equal to the cross-sectional area of the first passage portion 30 of the first tubular portion 20.

【0018】

In the expanded state, the guide pin 90 is arranged in the second end 84 of the arcuate slot 80 of the second tubular portion 40, and the second tubular portion has an arcuate shape. At the second end 62 of the second tubular portion 40, the second passage portion 74 has a diameter D3 (FIG. 3) that is greater than the diameter D2 of the second passage portion of the first end 60. doing. The diameter D3 of the second passage portion 74 at the second end 62 of the second tubular portion is preferably 40% to 80% larger than the diameter D1 of the second passage portion of the first end 60. .. Thus, in the inflated state, the cross-sectional area of the second passage portion 74 at the second end 62 of the second tubular portion 40, which is a function of diameter D3, is the first of the second tubular portions. It is 40% to 80% larger than the cross-sectional area of the second passage portion at the end 60.

【0019】

The cannula 10 includes an outer layer 100 (FIG. 1) that keeps the second tubular portion 40 of the cannula in a contracted state. Other suitable means of keeping the second tubular portion 40 in a contracted state may also be employed. According to one preferred embodiment of the invention, the outer layer 100 heats the outside of both the first tubular portion 20 and the second tubular portion 40 in order to keep the second tubular portion in a contracted state. It comprises a portion of a heat shrunk plastic tube 102.

【0020】

Further, a loop of nylon string 104 that strips the heat-shrink-fitted tube 102 is wrapped around the heat-shrink-fitted tube, and the loop extends at both the underside and top of the tube. The outer end 106 of the string 104 extends beyond the tube 102.

【0021】

The cannula 10 further comprises an actuable device 110 that inflates the second tubular portion 40 from a contracted state to an expanded state. According to one preferred embodiment of the invention, the actuable device 110 comprises a hand-operated expansion tool 112. The expansion tool 112 resembles a pair of common scissors and has a pair of legs 114 that are rotatably connected to each other. The expansion tool 112 has a conical end portion 116 formed by a pair of conical half bodies 118. Each of these cone-shaped halves 118 extends from each one of the legs 114 of the expansion tool 112. It is believed that other suitable means of inflating the second tubular portion 40 towards the inflated state, such as an inflatable balloon (not shown), may be employed.

【0022】

During endoscopic surgery, the cannula 10 is inserted into the patient's body in a contracted state. The surgeon then pulls the outer end 106 of the string 104 by hand. Pulling on the string 104 pulls off the heat-shrink-fitted tube 102, after which the surgeon removes the tube from the cannula 10. With the heat-shrink-fitted tube 102 removed, the second tubular portion 40 of the cannula 10 is thereby released to allow it to expand towards its extended state.

【0023】

The expansion tool 112 is then inserted into the passage 16 of the cannula 10 until the conical end 114 is placed at the second end 62 of the second tubular portion 40. The legs 114 of the expansion tool 112 are separated by hand so that the conical half body 118 is also separated. When the half body 118 is separated, the half body 118 applies a radial outward force to the inner surface 70 of the second tubular portion 40 so that the second tubular portion expands toward the inflated state. Under the force of the expanding expansion tool 112, the guide pin 90 slides from the first end 82 of the arc slot 80 to the second end 84 of the arc slot to inflate the second tubular portion 40. Allow that. The inflating tool 112 is rotated around the axis 14 so that the second tubular portion 40 of the cannula 10 is fully inflated to the inflated state. The inflatable tool 112 can then be folded and removed to allow one or more surgical instruments (schematically illustrated with reference number 120 in FIG. 5) to be accepted through the cannula 10 and inserted into the patient's body 130. ..

【0024】

The inflatable second tubular portion 40 of the cannula 10 provides a significantly larger area of action for the surgeon within the body 130 within the sealed portion of the cannula. As a result, a number of endoscopic surgical instruments can be inflated, including, but not limited to, steerable instruments, shavers, dividers, scissors, forceps, retractors, dilators, and video cameras. The cannula 10 allows them to be used at the same time.

【0025】

It is believed that the cannula 10 described herein can be a central element of an endoscopic surgical kit that includes a type of surgical instrument designed and / or selected for use with the cannula. Be done.

【0026】

From the above description of the present invention, those skilled in the art will recognize improvements, changes and modifications. Such improvements, modifications and modifications belonging to the art of those skilled in the art are intended to be included in the appended claims.

[Simple explanation of drawings]

[Figure 1]

FIG. 3 is an exploded perspective view showing an inflated state of a surgical cannula having a structure according to the present invention.

[Figure 2]

It is a perspective view which shows the contracted state of the cannula of FIG. 1 with parts removed for clarification.

[Fig. 3]

It is a schematic end view which shows the expanded state of the cannula of FIG.

[Fig. 4]

It is a development view of a part of the cannula of FIG.

[Fig. 5]

FIG. 5 is a schematic cross-sectional view showing the cannula of FIG. 1 during surgery.

[Explanation of symbols]

10 Cannula 12 Tube structure 14 Axis 16 Aisle 20 First tubular part 22 Base end of first tubular part 24 End of first tubular part 26 Cylindrical inner surface 28 Cylindrical outer surface 30 First passage 40 Second tubular part 42 Arc-shaped part of the second tubular part 44 First arc-shaped edge 46 Second arc-shaped edge 48 First planar edge 50 Second planar edge 60 First end 62 Second end 64 central part 66 rivets 68 Aligned holes at the first end 70 Parallel inner surfaces 72 Parallel outer surface 74 Second passage 80 Arc slot 82 First end 84 Second end 90 Guide pin 92 washer 100 outer layer 102 Plastic tube 104 Nylon string 106 Outer end of string 102 Tube 110 Operable device 112 Expansion tool 114 Legs 116 Head Conical end 118 Conical half body 130 Body