Surgical fastener applying instrument for ligating and dividing tissue
This is a continuation of application Ser. No. 07/835,233 filed on Feb. 13, 1992 now abandoned. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an apparatus for dividing body tissue, and more particularly to such an apparatus which may be employed to ligate and divide tubular vessels in endoscopic surgical procedures. 
     2. Background of the Art 
     Apparatus for ligating and dividing organic tubular structures (e.g., blood vessels and the like) are known and are commonly used in various surgical operations such as esophageal and gastric procedures. Generally such apparatus have a means for grasping the tubular structure, means for ligating the structure in two locations, usually by the application of staples, clips or the like, and means for dividing the tubular structure between the ligated portions, usually by slicing it with a knife. 
     U.S. Pat. No. 3,665,924 describes a ligating and dividing instrument which includes a cartridge for housing a plurality of staples. The instrument operates in three stages: after the tubular structure is inserted between the jaws of the cartridge, the cartridge jaws close, a pair of pushers come forward and suture the organic structure in two spaced locations with a pair of surgical staples, and a blade comes forward and divides the tubular structure. Other ligating and dividing instruments are disclosed in U.S. Pat. Nos. 4,086,926; 4,201,213; 4,349,028; and 4,556,058. 
     While the various known ligating and dividing apparatus have provided beneficial features to surgeons in the performance of non-endoscopic surgical operations, they are not useful in endoscopic or laparoscopic procedures. In laparoscopic procedures surgery is performed in the interior of the abdomen through a small incision. An endoscopic operation is one in which a surgical procedure is carried out in any hollow viscus of a human (or animal) body by means of instrumentation for operating or viewing deployed through one or more tubes. In either laparoscopic or endoscopic surgery, the functional portion of the instrumentation is manipulated or controlled from outside the body. Laparoscopic and endoscopic procedures generally require that any instrumentation inserted into the body be sealed, i.e., provisions must be made to ensure that gases do not enter or exit the body through the laparoscopic or endoscopic incision as, for example, in surgical procedures in which the surgical region is insufflated. Laparoscopic and endoscopic procedures often require the surgeon to operate on organs, tissue, and vessels far removed from the site of the incision, thereby requiring that any instruments to be used in such procedures be both long and narrow. Mechanical actuation of such instruments is for the most part constrained to movement of the various components along a longitudinal axis, even if lateral movement is employed at the operating site. The initial opening in the body tissue to allow passage of the endoscopic tube to the interior of the body can be a natural passageway of the body (e.g. bronchial tubes), or it can be a puncture produced by a tissue piercing instrument such as a trocar. Because the endoscopic tubes, instrumentation, and any required puncture are relatively narrow, endoscopic surgery is less invasive and causes much less trauma to the patient as compared with surgery in which the surgeon is required to cut open large areas of body tissue. It would be advantageous to have an endoscopic ligating and dividing instrument, and we have developed an apparatus to meet this need. 
     SUMMARY 
     An apparatus is provided herein for endoscopically applying surgical fasteners, i.e., surgical clips to body tissue, the apparatus including an endoscopic portion which has a longitudinal axis and terminates in a distal end for positioning near the body tissue, and further having means for moving at least two fasteners longitudinally for applying the fasteners to the body tissue at spaced apart locations thereon. 
     More particularly, an apparatus is provided herein for endoscopically ligating and optionally dividing body tissue. The endoscopic portion of the apparatus includes clip closing means for substantially simultaneously applying at least two surgical clips to the body tissue at spaced apart locations, movable catch means to engage the body tissue and position said body tissue for operation by said jaw means, pusher means for individually advancing at least two surgical clips simultaneously to the clip closing means, knife means for cutting said body tissue at a position between said spaced apart locations of the clips, and a longitudinally extending tube for at least partially enclosing and supporting the clip closing means, pusher means, catch means, and knife means. 
     The clip closing means includes at least two pairs of opposing jaws, each pair being laterally movable between an open position wherein the jaws of each pair are spaced apart a relatively wider distance and a closed position wherein the jaws of each pair are in close proximity to each other. Each of the jaws possesses at least one camming surface. The jaws can distally extend from one member. Preferably, each pair of jaws extend distally from a separate member. Each pair of jaws is mounted to and integrally constructed with a corresponding pair of prong portions of the member, the pairs of jaws being resiliently biased to said open position. 
     A supply of clips is preferably stored in two parallel, longitudinally oriented rows in the endoscopic tube. The pusher includes means for moving the furthest clip at the distal end of each of said two rows into position in the clip closing means. 
     The knife means includes an elongated member having distal and proximal ends and extending longitudinally through the tube and a tissue cutting blade mounted to the distal end of the elongated member. The tissue cutting blade is movable between a distal position and a proximal position. 
     The catch means includes at least two elongated members, each having a distal end portion and a proximal end portion, each member being longitudinally movable between a proximal position and a distal position, and each member having a tissue reception space defined by a hook configuration of said distal end portion. The distal end portions are fixedly attached to a spacer member located therebetween, and the proximal end portion are connected to the catch actuation means. 
     The pusher means includes at least two elongated members, each being longitudinally movable between a proximal position and a distal position, and each having a distal end portion and a proximal end portion. 
     The non-endoscopic portion of the apparatus includes a housing, which supports and at least partially encloses a knife actuation means, catch actuation means, pusher actuation means, and jaw actuation means. 
     The proximal end of the elongated member of the knife means is connected to the knife actuation means and the knife actuation means is distally movable between a proximal position and a distal position in response to user applied pressure. The knife actuation means is preferably biased by resilient means to the proximal position. 
     The catch actuation means includes a member slidably mounted to the housing, the member being longitudinally movable between a proximal position and a distal position in response to user applied pressure. 
     The pusher actuation means includes a member slidably mounted to said housing, said member being longitudinally movable between a proximal position and a distal position in response to user applied pressure. Preferably, the pusher actuation means is biased by resilient means to the proximal position. 
     The jaw actuation means includes at least one elongated member having a distal end portion and a proximal end portion, the distal end portion including at least one edge for contacting the camming surfaces of the jaws and urging the respective pairs of jaws laterally inward to the closed position, the elongated member(s) being longitudinally movable between a distal position wherein the pairs of jaws are cammed to the closed position and a proximal position wherein the pairs of jaws are in the open position. 
     The jaw actuation means further includes trigger means connected to the proximal end portion of the elongated member(s) of the jaw actuation means, the trigger means being movable between a jaw opening position and a jaw closing position in response to a user applied force. The trigger means is pivotally mounted to the housing such that movement of the trigger means from said jaw opening position to said jaw closing position advances the elongated member(s) of the jaw actuation means to the distal position wherein said jaws are cammed closed. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of the ligating and dividing apparatus of the present invention. 
     FIGS. 2 and 3 are, respectively, plan and side elevational views of the distal portion of the apparatus. 
     FIGS. 4 and 5 are exploded perspective views of the endoscopic portion of the apparatus. 
     FIG. 4a is a detailed perspective view of the distal portion of the track member. 
     FIGS. 6 and 7 are sectional view of the endoscopic portion of the apparatus. 
     FIG. 8 is a cutaway side elevational view of the handle portion of the apparatus. 
     FIGS. 9, 10, 11, 12, 13 and 14 are perspective views respectively illustrating: loading of a clip into the jaws of the apparatus, capture of a tubular structure, moving the tubular structure into position between the jaws of the instrument, closing the jaws of the instrument to apply the clip to the tubular structure, cutting the tubular structure, and release of the tubular structure. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENT(S) 
     1. Preface 
     An endoscopic clip applier is described in U.S. application Ser. No. 07/381,265 filed on Jul. 18, 1989 and herein incorporated by reference. 
     In the following description it should be noted that such terms as &#34;distal&#34; and &#34;proximal&#34;, &#34;upper&#34; and &#34;lower&#34;, &#34;horizontal&#34; and &#34;vertical&#34;, &#34;above&#34; and &#34;below&#34;, are used relative to each other and do not refer to positions or orientations relative to an external frame of reference. The term &#34;endoscopic&#34; as used herein with reference to apparatus and procedures shall also encompass laparoscopic apparatus and procedures. 
     Because endoscopic procedures are more common than laparoscopic procedures, the present invention shall be discussed in terms of endoscopic procedures and apparatus. However, use herein of terms such as &#34;endoscopic&#34;, &#34;endoscopically&#34; and &#34;endoscopic portion&#34;, among others, refer generally to instruments having elongated and relatively narrow operating portions for inserting into a cannula, body opening, or small wound in the skin and should not be construed to limit the present invention to an apparatus for applying surgical clips only in conjunction with an endoscopic tube. To the contrary, the present invention may find use in any procedure where access is limited to a small incision or body opening, including, but not limited to laparoscopic procedures. 
     2. Overview of the Apparatus 
     FIG. 1, illustrates a preferred embodiment of the apparatus of the present invention. The apparatus is preferably constructed as a disposable item of several materials as will be described. Essentially, however, two basic materials are used: a polycarbonate plastic such as LEXAN brand polycarbonate produced by General Electric Company, and stainless steel. Polycarbonate is a high strength polymer which exhibits superior dimensional stability even under relatively high stresses, and is also biologically compatible. 
     Briefly, the apparatus 100 includes an endoscopic portion 101, having an operating portion 102 and a non-endoscopic portion 200. The endoscopic portion is of such diameter so as to be insertable into a cannula inserted through a wall of body tissue for operation at an operating site in the interim of the human (or animal) body. The apparatus is manipulated to locate the operating portion 102 in position for operating on the body tissue. The non-endoscopic portion 200, which remains outside the body, has the various actuators which the surgeon employs to perform the operation. After the operation is completed, the apparatus 100 is withdrawn. The apparatus is intended to be disposed of after the operation. 
     The clips 190 (See FIGS. 4, 4a, and 5) are preferably fabricated from a strong flexible and ductile material capable of undergoing deformation without breaking, and which is suitable for use in surgical applications without causing adverse body reactions, i.e., it must be biocompatible. Metals are usually used for fabricating such clips, and commonly used metals include stainless steel, tantalum, and titanium. Polymeric materials may also be used provided they have the requisite mechanism and biological properties. Clips of generally U-shape or V-shaped configuration of the type generally suitable for use in the apparatus described herein are described in U.S. Pat. Nos. 4,976,722; 4,844,066; 4,188,953; and 3,363,628. 
     3. The Endoscopic Portion 
     Referring to FIGS. 1, 2, and 3 an embodiment of the endoscopic ligating and dividing instrument of the present invention comprises an endoscopic portion 101 and a non-endoscopic actuation portion 200. At the distal end of the endoscopic portion 101 is the operating portion 102 which includes tissue grasping assembly 104 having hook members 130 and 140 for grasping and pulling tubular organic body tissue, means such as movable clip closing means 110 and 120 for applying at least two clips to the tubular organic body tissue at spaced apart positions, means such as clip pushers 210 and 220 for loading at least one clip 190 (FIGS. 4 and 5) into each clip closer, and means such as knife 191 (FIG. 4) for cutting the tissue at a position between the two clips. 
     The non-endoscopic portion 200 of the apparatus (FIG. 1) includes hook retractor means 380, clip loader actuation means 390, clip closer actuation means 290, and knife actuation means 370, as well as housing 350 and handle means 351 for support by the user. 
     Referring now to FIGS. 2, and 3, which illustrate the operating portion 102 of the instrument, tissue grasping assembly 104 includes hook members 130 and 140 which are fiat members with distal end portions 132 and 142 each having an opening 131 for receiving body tissue, as will be illustrated below. Screws 106 fasten the distal end of the hook members to an anvil or spacer member 103 located between them at the distal end of the apparatus 100. 
     Clip closers 110 and 120 each include a pair of jaws 111 and 121, respectively, which project distally from the elongated outer tube 105. The outer tube 105 is adapted to fit through the cannula of a trocar assembly during an endoscopic surgical procedure. Outer tube 105 comprises upper and lower portions 105a and 105b which are adapted to fit together. When the apparatus is assembled, the upper and lower portions 105a and 105b may be bonded together by adhesive or other means, or they may be fabricated so as to snap fit together for secure joining. The proximal end of outer tube 105 possesses a circumferential flange 105C to facilitate mounting to the non-endoscopic portion 200. 
     Referring to FIGS. 4, 4a, 5, 6, and 7, clip pushing rods 210 and 220 each comprise an elongated member having a distal end portions 211 and 221, respectively, for individually advancing a clip 190 at the distal end of a row of clips into a respective pair of jaws 111 and 121. Rods 210 and 220 also each have a proximal end 212 and 222, respectively, for mounting to an actuator, discussed below. Clip tracks 230 and 240 for clips 190 are elongated members which serve to orient the respective rows of clips 190 longitudinally along the axis of the endoscopic portion 102. Tracks 230 and 240 each include a longitudinally extending slot 234 and 244, respectively, and a mounting post 235 and 245, respectively. Also included on the tracks are wing-like projections 236 and 246, respectively, which fit into corresponding slots in the outer tube 105 so as to secure the tracks in a fixed position relative to the instrument. The tracks include distal ends 231 and 241, respectively, which are described in more detail below with reference to FIG. 4a. 
     Spring retainer pins 330 and 340 are mounted on mounting posts 235 and 245, respectively, by means of apertured rear or proximal portion 331 and 341, respectively. Each spring retainer pin 330 and 340 possesses a distally extending pin portion 332 and 342, respectively, to which springs 310 and 320 are mounted. Springs 310 and 320 provide biasing force to urge the rows of clips 190 distally forward. Clip row advances 250 and 260 are elongated members each having a proximal end 252 and 262, respectively, for mounting to the distal end of springs 310 and 320, respectively. The distal end 251 and 261 of the clip row advancers is forked and is configured and dimensioned so as to engage the rear (proximal-most clip in the row of clips. Clip row advancers 250 and 260 each have a bend 253 and 263 dividing the advancers into two portions: a proximal portion 254,264 which is located at one side of the respective clip tracks 240, 250 and engages the respective one of the springs, and a distal portion 255, 265 which is located on the opposite side of the respective clip track where the clip row is located. Thus, bend portion 253 and 263 ride through slots 234, 244, respectively. 
     Attached to clip tracks 230 and 240 are channel members 270 and 280, which mount to the sides of the track members opposite that upon which the clips 190 ride. Channel members 270 and 280 possess flaps 271 and 281 which are preferably spot welded to wings 236 and 246 of the tracks. As can be seen from FIGS. 4 and 5, the channel members 270 and 280 are configured so as to form an elongated longitudinally extending channel of substantially semicircular cross section. The springs 310 and 320 are mounted in these channels. The proximal portions 254 and 264 also ride in the channels formed by channel members 270 and 280, respectively. Bends 253 and 263 enable the clip row advancers 250 and 260 to exert distal biasing force on the clips, which are located on the other side of the track member. 
     Referring to FIG. 4a, distal portions 231 and 241 of the respective track members 230 and 240 include side walls 232 to which spring clips 233 are attached, escapement 237a, 237b, and 237c, and guide flaps 238. The escapements provide for sequential advancement of the clips, i.e., the escapements limit the advancement of the clips 190 to one clip at a time. Thus, the distal-most clip passes over proximal escapement 237c and lodges between escapement 237c and escapements 237b. Spring clips 233 contact the legs of the clip and maintain it in position as it is advanced to the jaws 111 and 121. A novel feature of the present invention is that the distal portions 231 and 241 are resiliently flexible and bend at location 239. This feature enables the distal portions 231 and 241 to occupy the same space as the distal portion of the camming members 150 and 160 (discussed below), but at a different time. Thus, distal portions 231 and 241 are positioned so as to align the clips 190 with the jaws 111, 121 when the clips are advanced to the jaws. However, when the jaws 111, 121 are closed by advancing the camming members 150 and 160, the distal portions 231 and 241 flex outwardly to get out of the way of the camming members. This arrangement allows the construction of an endoscopic section with a smaller diameter than that which would be required if the distal portions 231 and 241 were not resiliently bent towards the center. 
     The jaws 111 and 121 are mounted to distally projecting resilient pairs of prongs 112 and 122, respectively, and each jaw possesses a notch 113 and 123, respectively, for holding the leg of a clip 190. The pairs of prongs 112 and 122 are initially in a spread apart configuration such that the pairs of jaws 111 and 121 are biased to the open position when pressure is applied by camming means. However, because of their flexibility, the pairs of prongs 112 and 122 bend laterally inward to permit closing of the pairs of jaws. The jaw members 110 and 120 each have crenelated end portion, 114 and 124, respectively, which is adapted to fit in a corresponding crenelated portion of the tubular members 105a, 105b in order to secure the position of the jaw members 110 and 120 relative to the instrument. The closing of the pairs of jaws is accomplished by distally moving camming members 150 and 160 which contact camming surfaces 114 and 124, respectively, to force the jaws 111 and 121 inward. 
     Camming members 150 and 160 each comprise an elongated camming member having distal camming edges 151 and 161, respectively. Laterally extending bars 152, 162 connect the proximal ends of camming members 150 and 160 to the trigger 290 as explained below. 
     The camming members 150 and 160 each have an inner plate 153 and 163, respectively. Side plates 154 and 164 join the distal end portions of the camming members 150 and 160 to form a box-like structure. Jaw member 110 is disposed through the space defined by the conjunction of camming member 150 and inner plate 153, and jaw member 120 is disposed through the space defined by the conjunction of camming member 160 and inner plate 163. 
     Knife covers 170 and 180 each include a tissue stopping distal edge 171 and 181, respectively, for preventing body tissue from moving proximally beyond the range of the jaws 111 and 121. Knife covers 170 and 180 each further include a proximal end portion having a plurality of lateral projections 172, 182, respectively, for facilitating mounting to the interior of the tube 105. The knife covers are in a fixed position relative to the instrument and do not move. The knife covers mount together to form a chamber through which knife 191 slides. The knife covers 170 and 180 may be fabricated from a polymer such as polycarbonate plastic. 
     Knife member 191 is an elongated member which includes distal knife edge 192 for cutting tissue. Knife 191 is longitudinally slidable within the tube 105 and members 150 and 160. 
     Referring to FIG. 8, the non-endoscopic portion 200 of the apparatus includes housing 350 which includes handle portion 351 to provide gripping means for the user. 
     Trigger 290 is pivotally mounted to the housing 350 by pivot pin 291. The top of the trigger is pivotally mounted to the proximal end of the camming members 150 and 160 by means of lateral bar 152 such that when trigger 290 is pivoted towards handle 351, the camming members 150 and 160 are advanced distally to close jaws 111 and 121. 
     Knife advancing actuator 370 is slidably mounted to housing 350 and movable between a distal and proximal position. Its upper portion projects outside the housing 350. The upper portion of knife advancing actuator 370 includes an upper surface 371 for receiving pressure applied by a user&#39;s finger(s). Knife advancing actuator 370 also includes a lower portion 372 which is mounted to the proximal end 193 of knife 191. Spring 197 biases the knife advancing actuator 370 to a proximal position. At least one laterally projecting detent 373 rides in a corresponding longitudinally extending slot in the inside surface of housing 350, which provides a guide pathway for longitudinal movement of the knife advancing actuator 370. 
     Hook retracting actuator 380 is slidably mounted to housing 350 and movable between a distal and proximal position. Hook retracting actuator 380 has an upper portion projecting outside the housing 350 and an upper surface 381 for receiving pressure applied by a user&#39;s finger(s). The lower portion of the hook retracting actuator 380 is mounted to the proximal end of hook members 130 and 140. The upper portion of the hook retracting actuator 380 includes a flat proximal projection 383 having a lower detent 384. The projection is of such length that when the hook retracting actuator is pulled back to its proximal position the detent 384 rides down the upper rear surface 352 of housing 350 and resiliently snaps down over the proximal edge 353 to lock the hook in the rear proximal position. Hook retracting actuator 380 also includes at least one laterally projecting detent 385 which rides in a corresponding longitudinally extending slot in the inside surface of housing 350, which provides a guide pathway or longitudinal movement of the hook retracting actuator 380. 
     Clip advancing actuator 390, i.e. a clip pusher actuator is slidably mounted to the housing 350 and at least partially extends through aperture 354 in the housing thereby presenting surface 391 for receiving pressure from the user&#39;s finger(s). The clip advancing actuator is movable between a distal position and a proximal position and is attached at its distal end 392 to the proximal ends 212 and 222 of clip pushers 210 and 220. Spring 198 abuts the distal end 392 of the clip advancing actuator 390 and biases actuator 390 towards the proximal direction. The distal end of spring 198 abuts the proximal surface of the hook retraction actuator 380. 
     The actuation of the ligating and dividing instrument 100 is illustrated in FIGS. 9 to 14. Referring to FIG. 9, the endoscopic portion of the instrument 101 is inserted through a cannula and positioned such that the operating portion 102 is in proximity to the tissue to be operated upon, i.e., blood vessel 400, as illustrated. The surgeon advances a clip 190 to each of the jaws 111 and 121 by pressing the clip advancing actuator 390 (FIG. 8). The clips slide into slots 113 and 123, respectively. 
     Referring to FIG. 10, the operating portion 102 is maneuvered to position blood vessel 400 in the space 131 defined by the distal hook ends 132 and 142 of hook members 130 and 140. 
     Referring to FIG. 11, the hook members 130 and 140 are retracted to capture blood vessel 400. Retraction of the hook members 130 and 140 is achieved when the surgeon pulls back on hook retracting actuator 380 (FIG. 8). Tissue stops (FIGS. 4 and 5) 171 and 181 provide a proximal barrier to maintain tissue 400 between the pairs of jaws 111 and 121. 
     Referring to FIG. 12, the clips 190 are then applied to the blood vessel 400 when the surgeon pulls the trigger 290 (FIG. 8), thereby advancing camming members 150 and 160 and closing jaws 111 and 121. 
     Referring to FIG. 13, the surgeon presses knife advancing actuator 370 (FIG. 8) to push knife 191 forward, thereby dividing blood vessel 400. 
     Referring to FIG. 14, the jaws 111 and 121 are opened, the hook members 130 and 140 are advanced, thereby releasing the ligated and divided blood vessel 400. 
     While the above description contains many specifics, these specifics should not be construed as limitations on the scope of the invention, but merely as exemplifications of preferred embodiments thereof. Those skilled in the art will envision many other possible variations that are within the scope and spirit of the invention as defined by the claims appended hereto.