WO1995029641A1

WO1995029641A1 - Laparoscopic surgical instrument

Info

Publication number: WO1995029641A1
Application number: PCT/US1995/005135
Authority: WO
Inventors: William J. Schnell
Original assignee: Baxter International Inc.
Priority date: 1994-05-02
Filing date: 1995-04-20
Publication date: 1995-11-09
Also published as: TW272158B; US5569298A; AU2397095A

Abstract

A surgical instrument (10) has a hollow elongated shaft (14) for insertion into the body, the shaft having a longitudinal axis and supporting a pair of interacting pivotable jaws (30, 32) on its distal end and being connected at its proximal end to a first movable component (18) of an operating handle (12), with a reciprocable rod (24) located within the shaft. The rod (24) is connected to a second movable component (20) of the handle (12) for reciprocation within the shaft (14) when the first and second components (18, 20) are moved relative to each other. The jaws are pivotally connected by a pivot pin (36) supported on the shaft (14) transversely to the axis. Each of the jaws (30, 32) has a proximal end extending proximally from the pivot pin (36). Each of the proximal ends is provided with an elongated opening (46, 48) therethrough, each of the openings forming an elongated slot oriented at an oblique angle relative to the longitudinal axis of the shaft. The reciprocable rod (24) has a distal end extending into each slot (46, 48) whereby reciprocation of the rod causes the jaws (30, 32) to open and close.

Description

LAPAROSCOPIC SURGICAL INSTRUMENT

Field of the Invention

The present invention relates to surgical instruments such as laparoscopic scissors, dissec- tors or grasping jaws.

Background of the Invention

Laparoscopic procedures generally involve excising or manipulating tissue through an opening in the body typically through a cannula through which a pivoting jaw type surgical instrument is inserted. Various mechanisms have heretofore been proposed for actuation of the jaws of such devices. Examples are U.S. Patent Nos. 2,790,437; 5,171,256; 5,171,258; 5,172,700 and 5,192,298. Typically the instrument, including handle, shaft and working tip are all reusable. However, particularly in the case of scissors, the delicate blades dull or are easily damaged. Thus it is desirable and cost efficient to be able to replace just the working tip components of the instrument.

The prior art instruments have tended to either have one stationary jaw and one pivotal jaw or to use an actuating mechanism, for causing pivot¬ ing of both jaws, that has a significant number of working parts. A need has, thus, existed for an instrument wherein a simplified mechanism is provid¬ ed for causing pivoting of jaws or blades. Summary of the Invention

A major object of the present invention is to provide a surgical instrument of the endoscopic type naving a simplified mechanism for reciprocating a pair of jaws or blades. In accordance with one aspect of the invention, a pair of jaws, which may be in the form of dissectors, graspers or scissors, are both pivotally supported on the distal end of the instrument and are operated to open and close utilizing a minimum number of working parts. More specifically, it is an important aspect of the in¬ vention to operate a pair of jaws or blades about a pivot point that supports the jaws on the distal end of an endoscopic instrument tube or hollow shaft with pivoting about the pivot point being caused by reciprocation of a central rod reciprocal within the shaft. In accordance with a related object, the distal end of the reciprocal rod is εlidably posi¬ tioned in a pair of slots, one of which is provided in the proximal end of each of the jaws.

In accordance with a still further aspect of the invention, a pair of jaws is provided with slots in the proximal end thereof which slots are positioned at an oblique angle relative to the lon¬ gitudinal axis of the main shaft of the instrument. Briefly summarized, the invention provides a surgical instrument which has a hollow elongated shaft for insertion into the body. The shaft has a longitudinal axis and supports a pair of interacting pivotable jaws on its distal end and is connected at its proximal end to a first movable component of an operating handle, with a reciprocable rod located within the shaft. The rod is connected to a second movable component of the handle for reciprocation within the shaft when the first and second compo¬ nents are moved relative to each other. The jaws are pivotally connected by a pivot pin supported trans- verεely to the axis of the shaft. Each of the jaws has a proximal end extending proximally from the pivot pin. Each of the proximal ends is provided with an elongated opening therethrough, each the openings forms an elongated slot oriented at an oblique angle relative to the longitudinal axis of the shaft. The reciprocable rod has a distal end extending into each slot whereby reciprocation of the rod causes the jaws to open and close.

Further objects and advantages of the in- vention will be apparent from the following detailed description, accompanying drawings and appended claims. Brief Description of the Drawings

Figure 1 is a perspective view of a surgical instrument in accordance with the invention;

Figure 2 is an enlarged perspective fragmentary view of the distal tip portion of the instrument of Figure 1 ; Figure 3 is an exploded perspective view of the fragmentary portion of Figure 2 shown in an ex¬ ploded position to illustrate the specific details of the pivotal jaws of the instrument;

Figure 4 is an enlarged fragmentary side elevational view of the distal tip of the instrument of Figure 1 with interior parts illustrated by phan¬ tom lines;

Figure 5 is an enlarged fragmentary view of the distal tip shown in Figure 4 with the jaws piv- oted to the open position;

Figure 6 is a top plan view of the distal tip shown in Figure 4 taken along lines 6-6;

Figure 7 is a fragmentary side view of the handle working mechanism and proximal end of the reciprocal rod and hollow shaft of the device shown in Figure 1 taken along line 7-7 with parts in cross-section to show interior details;

Figure 8 is an enlarged fragmentary perspective view of an alternative embodiment of the invention with interior parts shown by phantom lines;

Figure 9 is an exploded view of the interi¬ or reciprocal rod and distal tip component of the embodiment shown in Figure 8; Figure 10 is an enlarged side elevational view of the distal tip portion of the embodiment of Figure 8 with interior parts shown by phantom lines and with some parts shown in cross-section for clar¬ ity of the working mechanism; and Figure 11 is a top plan view of the device of Figure 10 taken along line 11-11. Detailed Description of Preferred Embodiments

Referring more specifically to the draw¬ ings, a surgical instrument 10 is provided with a handle portion generally designated by numeral 12 to which is attached a hollow shaft 14 which supports a reciprocal jaw distal end tool 16. Handle compo¬ nent 12 includes pivotally connected components 18 and 20 provided with finger openings 19 and 21, re- spectively. The components 18 and 20 are pivotally connected at a point 22 for movement relative to each other. A central rod 24 is movably positioned within the interior of hollow shaft 14. Rod 24 is provided with an enlarged end 26 which is connected to a cap 28 carried at the top of pivotal handle section 20. Cap 28 is slidable upwardly and downwardly and contains a keyhole shaped opening 29 adapted to retain the enlarged end 26 when it is in the down position illustrated in Figure 1 but which allows removal of rod 24 when cap 28 is raised to enable enlarged end 26 to slide out of the enlarged end of opening 29.

End tool 16 includes reciprocable scissors blades 30 and 32 which are pivotally attached to the distal end component 34 of the instrument. As best seen in Figures 2 and 3, the blades are pivotally connected by means of a pivot pin 36 to a bifurcated distal end of tip component 34 which also is provid¬ ed with slots 35 on its lateral edges. Tip compo- nent 34 is provided with openings 38 to receive piv¬ ot pin 36. Similarly, the blades 30 and 32 are pro¬ vided with openings 40 and 42 to receive the pivot pin 36. Distal end component 34 is provided with a threaded shaft 50 which is received by mating threads 52 in the distal end of hollow shaft 14.

As best seen in Figure 3, the distal end 44 of central rod 24 is bent into a hook configuration, so that a section thereof is oriented transversely to the longitudinal axis of rod 24. The distal end portion 44 is adapted to be slidably received in lateral slots 35 of distal end component 34. The distal end 44 is also slidably received in slots 46 and 48, which are located in the proximal ends of blades 30 and 32. As best seen in Figure 3 slots 46 and 48 are located in the blades at an oblique angle relative to the longitudinal axis of the blades. The slots extend from a distal end adjacent the out¬ er lateral side of each blade and extend in a proxi¬ mal direction at an angle inclined toward the inner, or cutting surface sides of the respective blades 30 and 32. Thus, as the distal end 44 of rod 24 is re¬ ciprocated within hollow shaft 14 it slides within each of the slots 46 and 48 thereby causing the blades 30 and 32 to be reciprocated about pivot pin 36. The blades therefore are caused to open and close as the handle components 18 and 20 are opened and closed.

The closed position of the blades 30, 32 is seen in Figure 4, while the open position thereof is best seen in Figure 5.

As seen in Figure 7, a fluid inlet tube 60 communicates with the inside of tubular shaft 14. Orifice 60 can be closed by means of a cap, for ex¬ ample, of the snap-on plastic type 61. A spring biased detente ball 58 can be utilized to retain the rotational orientation of shaft 14 in a desired re¬ lationship. Handles 56 are attached to the exterior of shaft 14 to enable easy rotation thereof. Inden¬ tions 59 in the outer surface of shaft 14 receive detente ball 58.

Seals 62 of the rubber 0-ring type prevent fluid escape along the outside of shaft 14. Orific¬ es 63 are provided to allow fluid communication to the interior of shaft 14. Thus, a means of intro- ducing cleaning fluid to the interior of the recip¬ rocal members 14, 24 is provided.

As seen in Figure 1, an electrode 70 can be provided extending downwardly from scissors handle 18. Electrode 70 is adapted to receive electrical power for transmission to metal tube 14 and thence to the end effectors 30, 32 for use in cauterization procedures.

In the modified version of the invention shown in Figures 8-11, central reciprocable rod 24 is replaced with a two piece rod 124, 132. In the case of this embodiment, only tip assembly 116 is discarded. The proximal portion of the rod 124 re¬ mains as a permanent part of the handle assembly. As best seen in Figures 8 and 9, the distal end of rod 124 is divided into bifurcations 126 and 128. These bifurcations have inwardly extending projec¬ tions 127 and 129. Enlarged opening 130 is located proximally to the projections 127 and 129. The dis¬ posable distal tip assembly that carries the scis- sors blades 30 and 32 and the related working parts substantially the same as those described relative to Figures 1-7 is best seen in Figure 9. A shaft 132 is provided with a working end 44. Shaft 132 is provided with an indented portion 134 preferably formed by swaging an appropriate indentation on each side of the shaft. Indentations 134 are appropri¬ ately sized to be engaged by projections 127 and 129 to hold the assembly together in the retracted posi¬ tion illustrated in Figure 8. The shafts 124 and 132 are therein shown in the connected position withdrawn into the hollow lumen of shaft 114.

In addition to a scissors 30, 32, the end cutting instrument can take different forms. For example, in Figure 12, the end tool includes jaws 140 and 142 shaped to be used as a biopsy instru¬ ment. In the embodiment of Figure 13 , jaws are pro¬ vided with serrated mating jaw surfaces desirable in some dissection or grasping procedures. It will be apparent to those skilled in the art that still fur- ther forms of mating jaw surfaces can be actuated by the mechanism of the present invention.

It is, thus, seen that the invention has produced a novel and superior working mechanism for a surgical instrument utilizing working jaws. Those novel features are set forth with particularity in the appended claims.

Claims

CLAIMSWhat is claimed is:

1. A surgical instrument (10) comprising: a hollow, elongated shaft (14) for insertion into the body, said shaft (14) having a distal end supporting a tip component (34) , 5 said shaft (14) connected at its proximal end to a first movable component (18) of an operating handle (12), said distal tip component (34) having a longitudinal axis and a bifurcated distal end o supporting a pair of interacting pivotable jaws

(30, 32), said distal tip component (34) also having a pair of slots (35) on its lateral edges, said slots (35) being located at an oblique angle relative to a longitudinal axis of s said jaws (30, 32) , said jaws (30, 32) being pivotally connected by a pivot pin (36) supported transversely to the axis of said tip component (34) each of said jaws (30, 32) having a o proximal end extending proximally from said pivot pin (36) , each of said proximal ends being provided with an elongated opening (46, 48) therethrough, each of said openings (46, 48) forming an elongated slot oriented at an oblique 5 angle relative to said longitudinal axis, and

a reciprocal rod (24) being located within said shaft (14) , a proximal end of said rod (24) being connected to a second movable component

(20) of said handle (12) for reciprocation c within said shaft (14) when said first and second components (18, 20) are moved relative to each other, said reciprocable rod (24) having a distal end bent in a hook configuration having a section thereof oriented transversely to the longitudinal axis of said rod (24) said section extending into each of said slots (35) and said elongated openings (46, 48) of said jaws (30, 32) whereby reciprocation of said rod causes said jaws (30, 32) to open and close.

An instrument according to claim 1 wherein said jaws (30, 32) comprise scissors blades.

An instrument according to claim 1 wherein said reciprocal rod (24) is of one piece and extends through the entire length of said hollow elongated shaft (14) .

An instrument according to claim 1 wherein said reciprocal rod (24) is of two parts comprising a distal segment (132) and a proximal segment (130), said distal and proximal segments (127, 128) being connected to each other within said shaft.

An instrument according to claim 4 wherein the distal end (126) of the proximal segment of said rod is bifurcated and said bifurcations (127, 128) have inwardly extending projections, the proximal end of said distal portion having mating notches on the opposite sides thereof for engagement by said projections. An instrument according to claim 1 wherein each of said elongated slots in each of said jaws extends from a distal end located relatively closer to a lateral edge of said jaw and extends to a proximal end located closer to a cutting edge of said jaw.