Endoscopic instrument system

Abstract: An endoscopic instrument (10) system has a handle portion (14) with means for gripping the instrument, the shaft (56) extending from the gripping means and, means for actuating the instrument. A plurality of instrument end tools (14) are removably mountable on the end of the shaft (56) and each include means for engaging the actuating means so that an attached end tool (14) can be operated by the actuating means.

Description: The present invention relates to an endoscopic instrument system for surgical use, for example an endoscopy scissors instrument suitable for use with a trocar or cannula. A branch of endoscopic surgery is laparoscopic surgery which involves the use of a cannula that is inserted through an incision in the skin of the subject to provide access to an internal cavity, such as the thoracic cavity. An example of such a cannula is disclosed in Hasson U.S. Patent No. 5,002,557. Surgery is performed with a laparoscopic instrument, which typically includes a scissors handle and an elongate shaft terminating in a pair of pivoting jaws. The handle includes a scissors or pliers grip which, when squeezed and released, reciprocates a rod extending through the shaft to pivot the jaws. The jaws and shaft are sized to be inserted through the cannula into the body cavity where the surgery is to be performed. Similar devices are employed in thoroscopic and arthroscopic surgery. WO91/02493 discloses a device having two elongate elements at least a portion of which is formed from a pseudoelastic material. The elements are moved towards and away from each other to grasp or cut an object. The device may include actuating means. Pages 194 and 195 of the 1988 A esculap ENT catalogue disclose an instrument and end tool as defined in the preamble to claims 1 and 17. As with any surgical instrument, should the tool include sharpened jaws for cutting, it is desirable to maintain the sharpened edges as sharp as possible for each operation. Further, it is also desirable to design the instrument so that it can be easily and thoroughly cleaned after each operation. However, disadvantages with unitary instruments; that is, instruments in which the handle, shaft and cutting tool are permanently attached to each other, is that cleaning of the instrument and sharpening of the tool after each operation becomes time-consuming and costly. Accordingly, attempts have been made to provide laparoscopy instruments which minimize the time and expense of cleaning and sharpening. For example, some laparoscopy instruments are made in which substantially the entire instrument is constructed in plastics, except for the shaft rod and jaws, so that the entire instrument is disposable after each operation. Alternately, instruments such as those disclosed in Falk et al . U.S. Patent No: 4 569 131 are designed in which the handle is separable from the shaft and jaws, so that the unitary shaft, jaws and rod may be disposed after each use, or cleaned and sharpened separately from the handle. Disadvantages we have found with these types of designs is that the disposable component -- whether it be the entire instrument or only the shaft and cutting tool -- provide an undesirably high volume of medical waste which requires special disposal procedures. Further, disposable instruments made largely of plastic are somewhat flimsy and difficult to manoeuvre. Accordingly, there is a continuing need, not satisfied prior to the present invention, for a laparoscopy instrument which eliminates the need for repeated sharpening of the cutting surfaces of the instrument and which facilitates cleaning and reduces cross-contamination potential. In accordance with a first aspect of the present invention, we provide an endoscopic instrument system comprising: an instrument including a handle portion having means for gripping said instrument, means forming a shaft extending from said gripping means and means for actuating said instrument; and an instrument end tool comprising jaw means forming a pair of jaws, and support means supporting said jaw means, such that said support means is removably mountable on an end of said shaft, characterised in that said end tool includes a stub shaft slidably mounted in the support means and having an enlarged end for engaging said actuating means, whereby said end tool is operable by said actuating means such that at least one of the jaws can move relative to the other. The present invention provides in a second and alternative aspect thereof a disposable end tool comprising jaw means forming a pair of jaws adapted for use with an endoscopic instrument of a type having a handle portion including means for gripping said instrument, means forming an elongate shaft extending from said gripping means and means for actuating said instrument; the end tool comprising support means, preferably plastics, operatively supporting said jaw means such that the jaws can move relative to each other, the end tool further comprising link means engaging said jaws, said support means being attachable to said shaft end in a manner enabling coaction with said actuating means so that operation of the actuating means is effective to move said jaw means, is characterised in that the link means includes a stub shaft slidably mounted in said support means and having an enlarged end adapted to engage said actuating means. In a preferred embodiment the end tool is adapted for use in an instrument in which said shaft has a threaded open end opposite said gripping means, and rod means for actuating said instrument, said rod means being mounted within said shaft for slidable movement by said gripping means and having a clevis end adjacent said shaft end, the end tool being characterised in comprising: a support having a threaded inner end shaped to enable it to be threaded into said shaft end; the stub shaft mounted within said support for reciprocal movement and having the enlarged end protruding from said inner end shaped to enable it releasably to engage said clevis end; first and second links pivotally attached to said stub shaft within said support; and first and second jaws pivotally mounted on said support to effect a scissors movement, said first and second jaws being pivotally connected to said first and second links, respectively, whereby, in operation of said instrument incorporating said end tool, movement of said rod is effective to reciprocate said stub shaft whereby to effect said scissors movement of said jaws. In a third alternative aspect of the present invention there is provided a method of using an endoscopic instrument system according to the first aspect comprising the steps of: selecting an endoscopic instrument of a type having a handle portion including means for gripping said instrument, means forming a shaft extending from said gripping means and means for actuating said instrument; selecting an instrument end tool of a type having means for replaceably mounting said end tool on an end of said shaft, the end tool having a stub shaft slidably mounted in the support means and having an enlarged end for engaging said actuating means whereby said end tool is operable by said actuating means; mounting said end tool on said shaft; and subsequent to use of said instrument and end tool, removing said end tool from said shaft. In a preferred embodiment the said end tool is selected from among a plurality of end tools having different configurations for performing different tasks. In preferred embodiments, each of the end tools includes pivoting jaws which actually contact the tissue of the subject during the operation. The end tools preferably include plastics components which lower their cost, and are disposable. One advantage is that the disposable component of the entire instrument is relatively small, thereby minimizing the cost of using the instrument over several operations and minimizing the volume of medical waste comprised by the disposable components of the instrument. In a preferred embodiment, the handle portion includes pivoting scissor handles and an actuating rod which extends through the shaft. The rod terminates in a devis which receives the hemispherical tip of a stub shaft that is reciprocatably mounted within the end tool. The stub shaft is connected to a pair of pivoting jaws by links so that reciprocal movement of the stub shaft causes the jaws to pivot relative to the end tool in a scissors fashion. Preferably the support of the end tool is made of a glass fibre reinforced plastic and threads onto the open end of the handle shaft. The pivoting jaws of the end tools may be formed to perform a variety of tasks; for example, the jaws can be in the form of scissors, graspers, biopsy, or dissectors. Another advantage is that only the portions of the instrument which become most contaminated during an operation and are most difficult to clean (namely, the jaws and linkage operating the jaws) are disposed of with the end tool. In the preferred embodiment, a cleaning port extends through the handle portion and facilitates the flushing of the shaft with an appropriate liquid cleaning agent after each operation. A direct result of incorporating our laparoscopy instrument system in a hospital operating room procedure is that a relatively few handle portions need be present while having a relatively larger number of end tools, in contrast to prior procedures in which an extensive array of unitary instrument must be present. Further, each surgeon may be provided with a set of end tools, each performing a different function, and each selected from an array of end tools to suit the particular surgeon's needs and preferences. It will thus be seen that preferred embodiments of our endoscopic instrument system can eliminate the need for repeatedly sharpening the cutting jaws of the instrument; can allow the linkage components which are the most difficult to clean to be disposable, thereby obviating the necessity for repeated cleaning; can have a shaft portion which is easily cleaned after each operation; can have cutting surfaces and linkages which are disposable, but in a manner such that the volume of disposed equipment is minimized; can have a disposable cutting element in which the support component is made of a relatively inexpensive plastics material; can have a plurality of attachable end tools which can be customized for a particular practitioner or application; and are relatively easy to manufacture and utilize. The invention is hereinafter more particularly described with reference to and as shown in the accompanying drawings, in which:- Fig. 1 is a side elevation of the handle portion and one end tool of a preferred embodiment of endoscopic instrument system constructed according to the present invention; Fig. 2 is a section taken at line 2-2 of Fig. 1; Fig. 3 is a section taken at line 3-3 of Fig. 1; Fig. 4 is a detail of the instrument of Fig. 1 showing the shaft end in section and a portion of the end tool broken away; Fig. 5 is the detail of Fig. 4 in which the tool jaws have been pivoted to an open position; Fig. 6 is a side elevation of a gripper end tool for use in the system of Fig. 1; Fig. 7 is a side elevation of a biopsy end tool for use in the system of Fig. 1; Fig. 8 is a side elevation of a dissector end tool for use in the system of Fig. 1. As shown in Fig. 1, the endoscopic instrument system illustrated, generally designated 10, includes a handle portion, generally designated 12, and an end tool, generally designated 14. The handle portion 12 includes a scissors component 16 which is gripped by the user and has front and rear scissors handles 17, 18, respectively. Scissors handles 17 and 18 include finger loops 20, 22. Scissors handle 17 is attached to a cylindrical housing 24 and includes a clevis 26 which is engaged by scissors handle 18 and secured by a screw 28. When scissor handles 17, 18 are pivoted relative to each other about screw 28, the upper end 30 of handle 18 reciprocates relative to the housing 24. As shown in Fig. 2, the housing 24 includes a hollow interior 32 which receives an inner sleeve 34 of a rotatable coupling 36. The inner sleeve 34 includes a flange 38 having a plurality of orifices 40 spaced about its periphery. The coupling 36 includes a coupling body 42 having a plurality of cylindrical cavities 44, each receiving an extension spring 46 which urges a ball 48 against an adjacent one of the orifices 40. The balls 48 are larger in diameter than the orifices so that the orifices merely provide seats for the balls 48. The inner end 50 of the coupling body 36 includes an annular groove 52 which receives a split ring 54. The split ring 54 retains the. coupling body 42 on the flange 38. The body 42 is unitary with a hollow, elongate shaft 56 (see also Fig. 1). While the shaft 56 of the preferred embodiment is made of surgical stainless steel, it is within the scope of the invention to provide a flexible shaft. The external surface of the body 42 is knurled to facilitate grasping by a user. The coupling 36 enables the shaft 56 to be rotated relative to the housing 24 of the handle portion 12, and the engagement of ball 48 and orifices 40 provide detent stops. The housing portion 24 includes a lateral tube 57 which is capped by a removable nut 58 and communicates with the interior 32 of the housing. The tube 57 extends through an opening 60 in the sleeve 34 to communicate with the interior 62 of the coupling 36 and shaft 56. The handle portion 12 includes a rod 64 which extends through the interiors 62, 32 of the shaft 56 and housing 24, respectively. The rod includes an enlarged, cylindrical segment 66 which engages the interior or internal wall of the sleeve 34 for location purposes and a rear segment 68 which protrudes through an end opening 70 in the housing 24 to terminate in a spherical end 72. The housing 24 includes a plastic end cap 74 mounted in a dovetail slot 75 which provides a seal about the extension 68. The extension 68 passes through an orifice 76 in the cap and the end 72 of the extension is received within a devis 78 formed in the upper end 30 of the handle 18. Consequently, pivoting movement of the handle 18 relative to handle 17 causes the upper end 30 to reciprocate relative to the housing 24, causing the rod 64 to redprocate relative to the handle portion 12. As shown in Fig. 3, the outer end 80 of the shaft 56 includes a threaded interior surface 82. The end 84 of the rod 64 includes a clevis 86. The end tool 14 includes a support 88, preferably made of a glass filled plastic, such as 40% glass filled polyetherimide. Other plastics include polyethersulfone and polyetheretherketone. Support 88 has a threaded inner end 90 which is shaped to thread into the threaded interior 82 of the end 80 of shaft 56. The support 88 mounts a pair of jaws 92, 94, which are best shown in Fig. 4. The support 88 includes a pair of arms 96, 98 (see Fig. 3) which receive a rivet 100 that mounts the jaws 92, 94 for pivotal movement relative to the support and to each other. The jaws 92, 94 each include ears 102, 104 which are pivotally attached to links 106,108 by rivets 110, 112. The links 106, 108 are, in turn, pivotally attached to a knuckle 114 by a rivet 116. The knuckle 114 forms a portion of a stub shaft 118 which is slidably mounted within a passage 120 formed in the support 88. The stub shaft is sized such that an inner end 122 protrudes rearwardly from the threaded end 90 and terminates in a hemispherical tip 124 which is shaped to be seated within the clevis 86. As shown in Fig. 5, displacement of the rod 64 relative to the shaft 56 by pivoting the handle& 17,18 in the manner previously described causes the end 84 of the rod to displace the stub shaft 118 outwardly relative to the support 88. This outward displacement causes the links 106, 108 to pivot the jaws 92, 94 outwardly away from each other. Conversely, displacement of the rod 64 inwardly, caused by squeezing the handles 17, 18 together (see Fig. 1), causes the stub shaft 118 to be displaced inwardly relative to the support 88, so that the links 106, 108 draw the jaws 92, 94 together. Consequently, pivotal movement of handle 18 relative to handle 17 causes the jaws 92, 94 to pivot relative to each other. To remove the end tool 14 from the shaft 56, the support 88 is first threaded out of the threaded end 80 of the shaft 56. The loops 20, 22 of the handles 17, 18 are drawn together, which displaces the rod end 84 outwardly from the shaft end 80, exposing the clevis 86. Once the rod end 84 clears the shaft end 80, the tip 124 of the stub shaft 118 can be removed from the clevis 86 and the entire end tool 14 discarded. It is not necessary to remove the rod 64 from the handle portion 12 or disconnect the extension 68 from the handle upper end 30. Reattachment of a fresh end tool 14 is accomplished by reversing the aforementioned sequence of steps. Specifically, a fresh tool 14 is placed adjacent to the shaft end 80 and the tip 124 placed into the clevis 86. The handles 17, 18 are spread slightly and the support 88 is threaded into the shaft end 80. In the preferred embodiment, the threaded end 90 of the support 88 includes bosses 126 which are deformed by the threads of the threaded end 80 to prevent the inadvertent unthreading of the end tool 14. To clean the handle portion 12 of the instrument system 10, the tip 14 is first removed as previously described. Then, the nut 58 is removed from the tube 57 and a cleaning solvent is flushed through the interiors 32, 62 of the housing 24 and shaft 56 so that the solvent exists the end 80 of the shaft, thereby flushing any debris from the shaft. However, it should be noted that the connection of the tip 14 with the shaft end 80 minimizes the entry of contaminants within the interior 62, since the only openings are the seam between the shaft end and support 88 and the passage 120 and stub shaft 118. Figs. 6, 7 and 8 show alternate embodiments of the end tool 14 A , 14 B , 14 C , each designed to perform a specialized function and forming a component of the system 10. In 14 A , the jaws 92 A , 94 A include rear-facing sawtooth edges 128 such that the tip 14 A forms an alligator grasper. In Fig. 7, the end tool 14 B indudes jaws 92 B , 94 B which are shaped to form a biopsy. In Fig. 8, the end tool 14 C includes jaws 92 C , 94 C having sawtooth edges 130 to form a dissector.

Claims: An endoscopic instrument system (10) comprising: an instrument including a handle portion (12) having means (36) for gripping said instrument, means forming a shaft (56) extending from said gripping means and means for actuating said instrument; and an instrument end tool (14) comprising jaw means (92, 94) forming a pair of jaws, and support means (88) supporting said jaw means (92, 94), such that said support means (88) is removably mountable on an end of said shaft (56), characterised in that said end tool (14) includes a stub shaft (118) slidably mounted in the support means and having an enlarged end (124) for engaging said actuating means, whereby said end tool (14) is operable by said actuating means such that at least one of the jaws (92, 94) can move relative to the other. An endoscopic instrument system according to Claim 1, further characterised in that said gripping means (36) operates said actuating means. An endoscopic instrument system according to Claim 2, characterised in that said actuating means extends through said shaft (56) from said gripping means (36) to an attached end tool (14). An endoscopic instrument system according to any preceding claim, further characterised in that said end tool (14) includes scissors (92, 94). An endoscopic instrument system according to any preceding claim, further characterised in that said end tool (14) is connectable to said shaft (56) end by a threaded engagement (82, 90). An endoscopic instrument system according to any preceding claim, further characterised in that said actuating means includes a rod (64) extending from said gripping means (36) to an end tool (14) mounted on said shaft end (80). An endoscopic instrument system according to any preceding claim, further characterised in that said end tool (14) includes link means (106, 108) terminating in the enlarged end (124), and said actuating means includes means (86) for releasably engaging said enlarged end. An endoscopic instrument system according to Claim 7, further characterised in that said engaging means includes clevis means (86) for receiving said enlarged end (124) of an attached end tool (14). An endoscopic instrument system according to Claim 7, further characterised in that the support (88) of the end tool (14), attachable to said shaft (56) end, receives said link means (106,108), a first said jaw pivotally attached to said support (88) and to said link means (106, 108) and a second said jaw attached to said support (88), whereby movement of said link means (106, 108) in response to movement of said actuating means causes said first jaw to pivot relative to said support and to said second jaw. An endoscopic instrument system according to Claim 9, further characterised in that said link means (106, 108) includes said stub shaft (118) having said enlarged end (124) and being slidably received in said support (88), and a first link element (106, 108) interconnecting said stub rod (118) and said first jaw (92, 94), whereby sliding movement of said stub rod (118) is transmitted through said link element (106, 108) to pivot said first jaw. An endoscopic instrument system according to Claim 10, further characterised in that said second jaw is pivotally attached to said support (88), and said link means (106, 108) includes a second link element interconnecting said stub rod (118) and said second jaw, whereby said sliding movement of said stub rod (118) causes said first and second jaws to pivot relative to each other in a scissors movement. An endoscopic instrument system according to Claim 11, further characterised in that said first and second jaws (92, 94) comprise jaws of a scissors, of a dissector, of a grasper, or of a biopsy. An endoscopic instrument system according to any preceding claim, further characterised in that said shaft (56) is rotatably mounted on said gripping means (36). An endoscopic instrument system according to any of Claims 1 to 12, further characterised in that said shaft (56) is removable from said gripping means (36). An endoscopic instrument system according to any preceding claim, further characterised in that said gripping means (36) includes port means (57, 58) for flushing said shaft. An endoscopic instrument system according to Claim 15, further characterised in that said port means (57, 58) includes a stub tube (57) threaded into said gripping means communicating with said shaft (56). A disposable end tool (14) comprising jaw means (92, 94) forming a pair of jaws adapted for use with an endoscopic instrument (10) of a type having a handle portion (12) including means (36) for gripping said instrument, means forming an elongate shaft (56) extending from said gripping means (36) and means for actuating said instrument; the end tool (14) comprising support means (88), preferably plastics, operatively supporting said jaw means (92, 94) such that the jaws (92, 94) can move relative to each other, the end tool (14) further comprising link means engaging said jaws (92, 94), said support means (88) being attachable to a shaft end (80) in a manner enabling coaction with actuating means so that operation of the actuating means is effective to move said jaw means (92, 94), characterised in that the link means include a stub shaft (118) slidably mounted in said support means (88) and having an enlarged end adapted to engage said actuating means. An end tool according to Claim 17. further characterised in that said support means (88) includes an inner end (90) adapted to mount on said shaft end (80). An end tool according to Claim 18, further characterised in that said inner end (90) includes a threaded portion shaped to thread into said shaft end (80). An end tool according any one of Claims 17 or 19, further characterised in that said jaw means (92, 94) includes first and second jaws, said jaws being pivotally attached to said support means (88). An end tool according to Claim 20, further characterised in that said jaw means (92, 94) includes first and second links (106, 108) interconnecting said first and second jaws (92, 94), respectively, with said stub shaft (118), whereby, in operation of a instrument incorporating said end tool (14), reciprocating movement of said stub shaft (118) relative to said support means (88) in response to said actuating means is effective to cause said jaws (92, 94) to pivot relative to each other. An end tool according to Claims 20 or 21 further characterised in that said jaws (92, 94) form a scissors, a grasper, biopsy, or a dissector. An end tool according to any of Claims 17 to 22, further characterised in that said support means (88) is made of a glass filled polyetherimide, a glass filled polyetheretherketone or a glass filled polyethersulfone. A disposable end tool (14) according to Claim 17 wherein the end tool is adapted for use with an instrument (10) in which said shaft (56) has a threaded open end (82) opposite said gripping means (36), said means for actuating said instrument comprising rod (64) means being mounted within said shaft (56) for slidable movement by said gripping means and having a clevis end adjacent said end, the end tool (14) being characterised in comprising a support (88) having a threaded inner end (90) shaped to enable it to be threaded into said shaft end (80); the stub shaft (118) mounted within said support (88) for reciprocal movement and having the enlarged end (124) protruding from said inner end shaped to enable it releasably to engage said clevis (86) end; first and second links (106, 108) pivotally attached to said stub shaft (118) within said support (88); and further characterised in that said first and second jaws (92, 94) are pivotally mounted on said support (88) to effect a scissors movement, said first and second jaws (92, 94) being pivotally connected to said first and second links (106, 108), respectively, whereby, in operation of said instrument incorporating said end tool (14), reciprocating movement of said rod (64) is effective to reciprocate said stub shaft (118) whereby to effect said scissors movement of said jaws (92, 94). A method of using the endoscopic instrument system (10) of any of Claims 1 to 16 comprising the steps of: selecting an endoscopic instrument (10) having a handle portion (16) including means (36) for gripping said instrument, means forming a shaft (56) extending from said gripping means and means for actuating said instrument; selecting an instrument end tool (14) of a type having means for replaceably mounting said end tool (14) on an end of said shaft (56), the end tool (14) having a stub shaft (118) slidably mounted in the support means, and having an enlarged end (124) for engaging said actuating means, whereby said end tool (14) is operable by said actuating means; mounting said end tool (14) on said shaft (56), and subsequent to use of said instrument and end tool, removing said end tool (14) from from said shaft (56). A method according to Claim 26 of using the endoscopic instrument system of any of Claims 1 to 16 wherein said end tool (14) is selected from among a plurality of end tools (14) having different configurations for performing different tasks.

Inventors: COON DONALD B, MARLOW SCOTT C, NELSON JOHN T, PETRUSCHKE HAANS K, COON, DONALD B., MARLOW, SCOTT C., NELSON, JOHN T., PETRUSCHKE, HAANS K.
Applicants: MARLOW SURGICAL TECHNOLOGIES I, MARLOW SURGICAL TECHNOLOGIES,INC
Application year: 1993
Main classification: A61B17
IPC codes: A61B1, A61B19, A61B10, A61B17