US20050263563A1 - Surgical stapling device - Google Patents

Abstract

A surgical stapling device for applying an array of surgical staples to tissue is provided. The stapling device includes an approximation mechanism for moving a cartridge assembly and an anvil assembly between spaced and approximated positions and a firing mechanism for ejecting the array of staples from the cartridge assembly. A single trigger is operable to effect approximation and firing of the device. The device also includes an alignment pin assembly which can be selectively manually or automatically advanced. The anvil assembly includes a stiffener plate which allows the device to have a reduced head portion profile.

Description

• This application is a continuation of U.S. patent application Ser. No. 10/783,126, filed on Feb. 20, 2004, which is a continuation of U.S. patent application Ser. No. 09/687,815, filed on Oct. 13, 2000. Each of which is incorporated herein in its entirety by reference.
BACKGROUND
• 1. Technical Field
• The present disclosure relates generally to a surgical stapling apparatus and, more specifically, to a surgical stapling apparatus having a single trigger for approximating anvil and cartridge assemblies and for ejecting an array of staples from the cartridge assembly.
• 2. Background of Related Art
• Surgical stapling instruments used for applying parallel rows of staples through compressed living tissue are well known in the art, and are commonly used, for example, for closure of tissue or organs prior to transection, prior to resection, or in anastomoses, and for occlusion of organs in thoracic and abdominal procedures.
• Typically, such surgical stapling instruments include an anvil assembly, a cartridge assembly for supporting an array of surgical staples, an approximation mechanism for approximating the anvil and cartridge assemblies, an alignment pin assembly for capturing tissue between the cartridge and anvil assemblies and for maintaining alignment between the cartridge and anvil assemblies during approximation and firing, and a firing mechanism for ejecting the surgical staples from the cartridge assembly. The approximation mechanism and the firing mechanism generally include distinct actuators for effecting approximation and firing of the staples. The alignment pin assembly can be manually operated to advance an alignment pin from the cartridge assembly into engagement with the anvil or, alternatively, the alignment pin assembly can be automatically actuated upon operation of the approximation mechanism. In instruments having a manually operated alignment pin assembly, the actuator for the alignment pin assembly is disposed at a location spaced from the handle of the instrument.
• U.S. Pat. No. 4,930,503 to Pruitt discloses such a surgical stapling instrument. Pruitt's instrument includes a manually operated alignment pin assembly, an approximation mechanism including a rotatable knob actuator and a firing mechanism including a pivotable trigger. In use, a surgeon must first approximate the anvil and cartridge members by rotating the knob actuator. Next, the surgeon can advance the alignment pin assembly by advancing a knob supported on the central body portion of the instrument. Thereafter, the instrument can be fired by pivoting the trigger towards a stationary handle of the instrument.
• U.S. Pat. No. 5,697,543 to Burdorff also discloses a surgical stapling instrument having an approximation mechanism, a firing mechanism and an alignment pin mechanism. The approximation and firing mechanisms each include a distinct pivotable trigger actuator. The alignment pin mechanism is operatively associated with the approximation mechanism such that upon actuation of the approximation mechanism, the alignment pin assembly is automatically advanced.
• Known prior art surgical staplers are lacking in several respects. Firstly, the use of multiple actuators to effect approximation and firing of the instruments complicate the manufacture and operation of the instrument and, in most cases, require the surgeon to use two hands to hold and operate the instrument. Secondly, the instruments in which the alignment pin assembly is operatively associated with the approximation mechanism require that the instrument be approximated to advance the alignment pin assembly, despite the fact that a surgeon may prefer to advance the alignment pin assembly prior to approximation. In contrast, the instruments in which the alignment pin assembly is manually advanced typically require the surgeon to use a second hand to actuate the alignment pin assembly.
• Accordingly, a continuing need exists for a surgical stapling instrument which can be operated by a surgeon with a single hand and which includes an alignment pin assembly which can be automatically or manually advanced.
SUMMARY
• In accordance with the present disclosure, a surgical stapling device is provided which includes a frame having a proximal end and a distal end. A body defining a stationary handle is secured to the proximal end of the frame. A head portion including an anvil assembly and a cartridge assembly are supported on the distal end of the frame. The anvil and cartridge assemblies are movable in relation to each other between spaced and approximated positions. An approximation mechanism includes a clamp slide assembly having a distal end configured to support the cartridge assembly and a proximal end. A firing mechanism includes a thrust bar having a distal end positioned to be slidably received within the cartridge assembly. A pivotable trigger is supported on the body and is operably associated with the approximation mechanism and the firing mechanism such that the trigger is pivotable through an approximation stroke to approximate the anvil and cartridge assemblies and, subsequently, pivotable through a firing stroke to eject an array of staples from the cartridge assembly.
• The presently disclosed surgical stapling device also has an alignment pin assembly which includes an alignment pin, a pin pusher and a bell crank. The alignment pin pusher is slidably supported on the frame between advanced and retracted positions. The alignment pin pusher includes a distal abutment member for engaging and advancing the alignment pin from a retracted position located within the cartridge assembly to an advanced position engaging the anvil assembly. The bell crank is operably connected to the clamp slide assembly and is releasably coupled to the pin pusher. Upon advancement of the clamp slide assembly, the bell crank is pivoted to concurrently advance the alignment pin pusher. The alignment pin pusher includes a pair of posts which extend through slots in the body. A thumb button is supported on each post. The thumb button(s) can be pushed prior to approximation of the device to manually advance the alignment pin assembly into engagement with the anvil assembly. The thumb buttons are positioned on the body such that a surgeon is able to manually advance the alignment pin assembly using the same hand that actuates the pivotable trigger.
• A pawl mechanism is supported in the body and includes a clamping pawl and a firing pawl. The clamping pawl functions to prevent return of the approximation mechanism after the trigger has moved through approximately three quarters of the approximation stroke. The clamping pawl also provides an audible and tactile indication that the device has been moved to the approximately three quarter approximated position. The firing pawl functions to provide an audible indication that the device is in a fire-ready position. The firing pawl also functions to lock the trigger in a compressed position after firing of the device has occurred to provide a visual indication that firing has occurred. A release button is provided to return the approximation mechanism to the retracted position at any point of operation of the device. The pivotable trigger, the release button and the thumb button are all disposed adjacent the handle portion of the device and are operable by the surgeon using a single hand.
• The anvil assembly of the surgical stapling device is provided with a stiffener plate to provide increased strength to the assembly. By using the stiffener plate, the head portion profile can be reduced in size.
BRIEF DESCRIPTION OF THE DRAWINGS
• Preferred embodiments of the presently disclosed surgical stapling apparatus are described herein with reference to the drawings, wherein:
• FIG. 1 is a perspective view of one embodiment of the presently disclosed surgical stapling device;
• FIG. 2 is a side view of the surgical stapling device shown inFIG. 1;
• FIG. 3 is a top view of the surgical stapling device shown inFIG. 1;
• FIG. 4 is a perspective view with parts separated of the surgical stapling device shown inFIG. 1;
• FIG. 5 is a perspective view of the surgical stapling device shown inFIG. 1 with the left body half-section removed from the handle portion of the device;
• FIG. 6 is a perspective view of the handle portion of the surgical stapling device shown in
• FIG. 7 with a body half-section removed and a portion of the frame cutaway;
• FIG. 7 is an enlarged view of the indicated area of detail shown inFIG. 4;
• FIG. 8 is a rear perspective view of the staple pusher assembly of the surgical stapling device shown inFIG. 1;
• FIG. 8A is a rear perspective view of the staple pusher assembly shown inFIG. 8 with parts separated;
• FIG. 8B is a perspective view of an alternate embodiment of the staple pusher assembly shown inFIG. 8 with parts separated;
• FIG. 8C is a perspective view of the staple pusher assembly shown inFIG. 8B in an assembled state;
• FIG. 9 is an enlarged perspective view of the distal end of the surgical stapling device shown inFIG. 1;
• FIG. 9A is an enlarged view of the indicated area of detail shown inFIG. 9;
• FIG. 9B is a cross-sectional view taken alongsection lines9B-9B ofFIG. 9A;
• FIG. 10 is a perspective view from one side of the firing pawl of the surgical stapling device shown inFIG. 1;
• FIG. 10A is a perspective view from the other side of the firing pawl shown inFIG. 10;
• FIG. 11 is a perspective view from one side of the clamping pawl of the surgical stapling device shown inFIG. 1;
• FIG. 11A is a perspective view from the other side of the clamping pawl shown inFIG. 11;
• FIG. 12 is a perspective view with parts separated of the trigger and firing link of the surgical stapling device shown inFIG. 1;
• FIG. 13 is a perspective view with parts separated of the release button assembly and bi-linkage assembly of the surgical stapling device shown inFIG. 1;
• FIG. 14 is a perspective view with parts separated of the pin pusher and bell crank of the surgical stapling device shown inFIG. 1;
• FIG. 15 is a side cross-sectional view of the surgical stapling device taken along section lines XX-XX ofFIG. 3;
• FIG. 15A is a side partial cutaway view of the handle portion of the surgical stapling device shown inFIG. 1 with a body half-section removed;
• FIG. 15B is an enlarged view of the indicated area of detail shown inFIG. 15;
• FIG. 15C is an enlarged view of the indicated area of detail shown inFIG. 15A;
• FIG. 16 is a side cross-sectional view of the surgical stapling device shown inFIG. 1 during approximation of the anvil and cartridge assemblies;
• FIG. 16A is a side partial cutaway view of the handle portion of the surgical stapling device shown inFIG. 1 during approximation of the anvil and cartridge assemblies with the left body half-section removed from the handle portion of the device;
• FIG. 16B is an enlarged view of the indicated areas of detail shown inFIG. 16;
• FIG. 16C is an enlarged view of the indicated area of detail shown inFIG. 16A.
• FIG. 17 is a side cross-sectional view of the surgical stapling device shown inFIG. 1 in the approximated position with the trigger in the compressed position;
• FIG. 17A is a side partial cutaway view of the handle portion of the surgical stapling device shown inFIG. 1 in the approximated position with the left body half-section and frame removed from the handle portion of the device and the trigger in the compressed position;
• FIG. 17B is an enlarged view of the indicated area of detail shown inFIG. 17;
• FIG. 17C is an enlarged view of the indicated area of detail shown inFIG. 17A.
• FIG. 18 is a side cross-sectional view of the surgical stapling device shown inFIG. 1 in the approximated position with the trigger in a fire-ready position;
• FIG. 18A is a side partial cutaway view of the handle portion of the surgical stapling device shown inFIG. 1 in the fully approximated position with the left body half-section and frame removed from the handle portion of the device and the trigger in a fire-ready position;
• FIG. 18B is an enlarged view of the indicated area of detail shown inFIG. 18;
• FIG. 18C is an enlarged view of the indicated area of detail shown inFIG. 18A.
• FIG. 19 is a side cross-sectional view of the surgical stapling device shown inFIG. 1 after the device has been fired with the trigger in a compressed and locked position;
• FIG. 19A is a side partial cutaway view of the handle portion of the surgical stapling device shown inFIG. 1 in the fired position with the left body half-section and frame removed from the handle portion of the device and the trigger in the compressed position;
• FIG. 19B is an enlarged view of the indicated area of detail shown inFIG. 19;
• FIG. 19C is an enlarged view of the indicated area of detail shown inFIG. 19A.
• FIG. 20 is a side cross-sectional view of the surgical stapling device shown inFIG. 1 after the staples have been fired from the staple cartridge and the cartridge assembly has been moved to the retracted position;
• FIG. 20A is an enlarged view of the indicated area of detail shown inFIG. 20;
• FIG. 21 is a top view of tissue illustrating the staple configuration applied to tissue by the surgical stapling device shown inFIG. 1;
• FIG. 22 is a top view of the tissue shown inFIG. 16 illustrating the staple configuration after the tissue has been cut;
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
• Preferred embodiments of the presently disclosed surgical stapling device will now be described in detail with reference to the drawings, wherein like reference numerals designate corresponding elements in each of the several views.
• The presently disclosed surgical stapling device shown generally as10 inFIGS. 1-3 includes abody12 defining astationary handle14, apivotable trigger16, an elongatedcentral body portion18, acartridge assembly20 and ananvil assembly22. Athumb button24 is slidably positioned on each side ofbody12.Thumb buttons24 are movable to manually advance an alignment pin assembly in a manner to be described in detail below. Arelease button150 ofrelease mechanism26 is positioned on the proximal end ofbody12 and is depressible to allowcartridge assembly20 to return from an approximated position disposed adjacent toanvil assembly22 to a position spaced from anvil assembly22 (as shown). Operation ofrelease mechanism26 will also be described in detail below.
• Referring toFIG. 4,body12 is formed from a pair of molded half-sections12aand12b. Preferably, half-sections12aand12bare formed of plastic, although other materials including metals may be used to form the half-sections. A cushioned grippingmember14ais secured tostationary handle14 of each half-section12aand12b. Grippingmember14amay be formed by injection molding a thermoplastic elastomer, such as Versaflex™ or Santaprene, tostationary handle14. Alternately, cushioned grippingmember14 can be formed on or secured tostationary handle14 using any known fastening technique including adhesives, screws, welding, overmolding, etc. A pair of spacedframe members28aand28bextend between housing half-sections12aand12bandanvil assembly22. A central portion offrame members28aand28bform elongatedcentral body portion18. Preferably,frame members28aand28bare formed of a surgical grade metal such as stainless steel. Alternately, other suitable materials meeting the requisite strength requirements may also be used.
• Referring also toFIGS. 9-9B,anvil assembly22 includes astiffener plate30, aspacer plate32, a T-track34, and ananvil36. Anopening67 is formed inanvil36 to allow passage ofalignment pin38.Stiffener plate30 has avertical portion30aand ahorizontal portion30b. Anotch30cis formed in the distal end ofvertical portion30a.Notch30cis configured to receive thetip38aof acartridge alignment pin38.Horizontal portion30bofplate30 includes acutout40 dimensioned to receive aninterlock member42 which will be discussed in further detail below. In the assembled state, a distal vertical portion offrame members28aand28bare positioned on opposite sides ofvertical portion30aofstiffener plate30.Spacer plate32 includes a pair of legs which are positioned on opposite sides ofstiffener plate30 betweenstiffener plate30 andanvil36.Anvil36 defines achannel36aand is positioned aboutspacer plate32. Acap39 is positioned over the assembly to provide a smoother surface which is less likely to snag tissue during use.Cap39 includes agroove39awhich defines one end of a cuttingguide slot41 formed betweenanvil36 and frame member28b.Groove39aand cuttingguide slot41 facilitate cutting of tissue with a scalpel afterdevice10 has been fired. T-track34 defines a throughslot45.Slot45 is positioned overhorizontal portion30bofstiffener plate30 betweenframe members28aand28b. T-track34 is positioned aboutcutout40 to define a cavity in which interlock42 is positioned. Preferably, the anvil assembly components andframe members28aand28bare secured together using rivets44 (FIG. 5). Alternately, other fastening members may be used to secure the anvil assembly components and the frame members together including screws, pins, welding, etc. Preferably, the components ofanvil assembly22 are formed of stainless steel. Alternately, other materials, including metals, having requisite strength requirements can be used to form some or all of the anvil components.
• Referring toFIG. 9,anvil36 includes a plurality ofstaple pockets37 formed in the surface of the anvil. Eachstaple pocket37 includes first and secondstaple forming cups37aand37band a channelingsurface37cdisposed around each of the staple forming cups. An anvil including such a staple forming pocket has been disclosed in U.S. Pat. No. 5,480,089 filed Aug. 19, 1994, the entirety of which is incorporated herein by reference.
• Referring toFIGS. 4 and 7-8A,cartridge assembly20 includes acartridge50 having an array ofstaple receiving slots52. Astaple pusher assembly54 includes a plurality ofpusher members58. Eachpusher member58 includes a plurality offingers58aconfigured to be slidably received within a respectivestaple receiving slot52.Fingers58aare positioned behindstaples56 inslots52 such that advancement offingers58aeffects ejection ofstaples56 fromslots52. A guide channel60 (FIG. 15) formed incartridge50 is configured to slidably receivealignment pin38. Aspring64 is positioned aboutpin38 to urgealignment pin38 to a retracted position withinguide channel60. Anopening65 formed incartridge50 allowsalignment pin38 to extend fromguide channel60 through anvil opening67 (FIG. 9A) intonotch30cformed inanvil assembly22. Operation of the alignment pin mechanism for advancingalignment pin38 will be described in detail below.
• Referring also toFIGS. 8B and 8C,staple pusher assembly54 includesmultiple pusher members58 which interengage to formpusher assembly54.Pusher assembly54 may be modified by adding or subtractingpusher members58 to accommodate different size cartridges. For example, apusher member58 can be removed from the assembly such as shown inFIGS. 8B and 8C to accommodate a smaller cartridge assembly.
• Referring toFIGS. 4 and 5,surgical stapling device10 includes a pair ofclamp slide members66aand66b, analignment pin pusher68 and athrust bar70.Clamp slide members66aand66b,alignment pin pusher68 and thrustbar70 are slidably supported betweenframe members28aand28bfor movement between retracted and advanced positions in response to movement oftrigger16 through an approximation stroke and/or a firing stroke. Operation of each of the above members will be described in detail below.
• Clamp slide members66aand66bform part of the approximation mechanism of the surgical stapling device. Each clamp slide member has adistal end72, aproximal end74 and anelongated body76.Elongated body76 includes a pair ofelongated guide slots78aand78b.Guide slots78aand78bare dimensioned to slidably receivepins80aand80b(FIG. 15), respectively, which extend betweenframe members28aand28b. The positioning ofpins80aand80binguide slots78aand78bfunctions to maintain alignment betweenclamp slide members66aand66bandframe members28aand28bduring movement between the advanced and retracted positions and to limit the extent of longitudinal movement ofclamp slide members66aand66b, i.e., the fully advanced position of the clamp slide members is reached when the proximal end ofslot78aengagespin80aand the fully retracted position of the clamp slide members is reached when the distal end ofslot78aengagespin80a.Distal end72 of eachclamp slide member66aand66bincludes ahead portion82. Eachhead portion82 has a plurality ofopenings84 configured to receive a fastening member86 (FIG. 5) for securingclamp slide members66aand66btogether in spaced relation. In the assembled state, clampslide members66aand66bare spaced from each other to define an elongated channel in whichpin pusher68 and thrustbar70 are slidably disposed.Distal end72 ofclamp slide members66aand66bdefine a cartridge support receptacle for receivingcartridge assembly20. A series ofdimples85 on each of the clamp slide members function to frictionally retaincartridge assembly20 within the cartridge support.Proximal end74 ofclamp slide members66aand66beach include ahole87 for receiving apin88 of the actuation assembly which will be described in detail below.
• Referring also toFIG. 14,alignment pin pusher68 defines achannel69 along its length which is dimensioned to slidably receive thrustbar70.Alignment pin pusher68 includes avertical portion90 having anabutment member91 configured to engage theproximal end38b(FIG. 4) ofalignment pin38 such that whenalignment pin pusher68 is moved to an advanced position (in the manner described below),alignment pin38 is advanced from withincartridge50 throughopening65 incartridge50 andopening67 inanvil36 intonotch30cofanvil assembly22.Alignment pin pusher68 includes a pair ofelongated slots92aand92b.Pins80aand80b(FIG. 15) extend throughslots92aand92b, respectively, to guidealignment pin pusher68 during movement between the advanced and retracted positions. The proximal end ofalignment pin pusher68 includes a pair of spacedlegs68aand68b. Eachleg68aand68bincludes aradially extending post120 which is dimensioned to extend through elongated slots122 (FIG. 4) formed in body half-sections12aand12b.Thumb buttons24 are fastened toposts120 to facilitate manual actuation ofalignment pin pusher68. A C-clip receptacle126 is formed onalignment pin pusher68 and is dimensioned to releasably receivelink94 ofbell crank96. Operation of bell crank96 and the handle actuation assembly will be described in detail below.
• Referring again toFIG. 4, thrustbar70 is slidably positioned withinchannel69 defined withinalignment pin pusher68. The distal end ofthrust bar70 includes anengagement head100 configured to engagestaple pusher assembly54.Thrust bar70 also includes a pair ofelongated slots102aand102bwhich are dimensioned to slidably receivepins80aand80b(FIG. 15). As discussed above with respect to clampslide members66aand66b, pins80aand80bfunction not only to guide the movement ofthrust bar70 between the retracted and advanced positions, but also to define the fully advanced and fully retracted positions ofthrust bar70. As illustrated inFIG. 15,slots102aand102binthrust bar70 are longer thanslots78aand78bformed in clamp slides66aand66b, respectively. The increased length ofslots102aand102bpermit thrustbar70 to be advanced distally from the approximated position independently of clamp slides66aand66bthroughcartridge assembly20 to eject staples fromcartridge assembly20. The proximal end ofthrust bar70 is adapted to engage a biasingmember71 which is supported in tension betweenframe28aand thrustbar70 to urge thrustbar70 to the retracted position. The proximal end ofthrust bar70 also includes anotch104 which is configured to receive the distal end of afiring link106 and will be discussed in further detail below.
• Referring toFIGS. 4-6, and10-13, a handle actuation assembly includespivotable trigger16, abi-linkage assembly111 including afront link112 and arear link114, bell crank96, firing link106 a clampingpawl108 and afiring pawl110. Arelease mechanism26 includes arelease button150 and arelease lever152 provided withinbody12.
• Pivotable trigger16 is pivotably secured between body half-sections12aand12baboutpivot members116 which are integrally formed on opposite sides oftrigger16. Alternately, a pivot pin can be used topivotably support trigger16 between the body half-sections.Trigger16 includes a cushionedgrip16a, which may be secured to trigger16 in the manner discussed above with respect tostationary handle14, and arearward extension115 positioned beneathbi-linkage assembly111. Rear link114 ofbi-linkage assembly111 has a rear end pivotably secured aboutpivot pin113 which extends betweenbody members12aand12band a forward end pivotably fastened to the rear end offront link112 bypivot pin118. It is noted thatrelease button150 is also pivotably secured to pivotpin113. The forward end offront link112 is pivotably fastened to clampslide members66aand66bbypin88. Whentrigger16 is pivoted aboutpivot members116,rearward extension115 urgesbi-linkage assembly111 from a position in which the longitudinal axes of front andrear links112 and114 are misaligned to a position in which the axes of front andrear links112 and114 are substantially aligned. In the substantially aligned position, links112 and114 are moved to an overcenter position slightly past actual alignment. By moving the bi-linkage assembly slightly overcenter or past the aligned position,bi-linkage assembly111 will not return to the misaligned position until engaged by therelease mechanism26. Since the rear end ofrear link114 is fastened withinbody12, asbi-linkage assembly111 is moved from the misaligned to the aligned position,front link112 is advanced distally to advanceclamp slide members66aand66bdistally. Advancement ofclamp slide members66aand66beffects corresponding advancement ofcartridge assembly20 to effect approximation of anvil andcartridge assemblies22 and20, respectively.
• Referring toFIGS. 4 and 15, thrustbar70 includes a forwardelongated slot103.Rivets117, which extend betweenclamp slide members66aand66b, also extend throughslot103. Whenclamp slide members66aand66bare advanced from a retracted position to an advanced position, rivets117 engage the forward end ofslot103 to advance thrustbar70 concurrently withclamp slide members66aand66b. As illustrated inFIG. 15,slot103 is of a length to allow thrustbar70 to advance distally beyond the approximated position independently ofclamp slide members66aand66b.
• Referring toFIGS. 4 and 14, bell crank96 is pivotably secured betweenframe members28aand28bbypivot member134. As discussed above, link94 ofbell crank96 is releasably positioned within C-clipl26 ofalignment pin pusher68. Bell crank96 includes a pair of spaced sidewalls96aand96b. Each sidewall includes an inwardly extendingcam member138 which is configured to be received within acam slot140 formed in the proximal end of clamp slides66aand66b. As clamp slides66aand66bare advanced distally, the walls definingcam slots140 engagecam members138 to pivot bell crank96 aboutpivot member134. Whenbell crank96 is pivoted, post94urges pin pusher68 distally to advanceabutment member91 throughguide channel60 to advancealignment pin38 into engagement withanvil assembly22.Cam slots140 are configured to quickly pivot bell crank96 during the initial advancement of clamp slides66aand66bsuch as to quickly advancealignment pin pusher68 andalignment pin38 during the initial stage of approximation.
• Referring again toFIGS. 4 and 13,release mechanism26 includesrelease button150 andrelease lever152. As discussed above,release button150 includes a rear end which is pivotably secured to pivotpin113.Pivot pin113 is secured betweenbody members12aand12b. The forward end ofrelease button150 includes aslot154 dimensioned to slidably receive arod156 formed on a rear end ofrelease lever152. The forward end ofrelease lever152 is pivotably secured between body half-sections12aand12b. Anengagement member158 projects downwardly from the bottom ofrelease lever152 and is positioned to abutbi-linkage assembly111 whenrelease button150 is depressed to urgebi-linkage assembly111 from the substantially aligned overcenter position to the misaligned position.
• Referring toFIGS. 4 and 10-12,surgical stapling apparatus10 includes a pawl assembly including clampingpawl108 and firingpawl110. Clampingpawl108 is pivotably secured aboutpivot member170 in semi-circular slot172 (FIG. 4) inframe28a. Aspring174 is secured between clampingpawl108 and frame28ato urge clampingpawl108 to rotate in a clockwise direction as viewed inFIG. 4. Clampingpawl108 includes acam surface176 having arecess178 positioned to engage cam member180 (FIG. 16B) formed onextension115 oftrigger16. Whencam member180 ontrigger16 is positioned inrecess178 of cam surface176 (this occurs after the clamp slides66aand66bhave been moved through approximately three quarters of the approximation stroke),trigger16 is prevented from being returned byspring182 to a non-compressed position. Thus, thecartridge assembly20 and theanvil assembly22 are maintained in a three quarter approximated position even whentrigger16 is released by the surgeon. Firingpawl110 is pivotably secured aboutpivot member184 in semi-circular slot186 (FIG. 4) formed in frame28b.Spring188 is secured between firingpawl110 and frame28bto urge the firing pawl in a clockwise direction as viewed inFIG. 4. Firingpawl110 includes acam surface190 having arecess192 for engaging acam member180′ formed on a side ofextension115 oftrigger16opposite cam member180. During movement oftrigger16 through the firing stroke,cam member180′ is moved intorecess192 to locktrigger16 in a compressed position after firing has been completed. This provides an audible and visual indication to the surgeon that firing has been completed. Additional operational details of the pawl assembly will be described in the following description of the operation ofsurgical stapling device10.
• Operation of the surgical stapling device will now be described in detail with reference toFIGS. 15-20A. It is noted that the movements of the various components will be described from the vantage point of one viewing the instrument as positioned in the referenced FIG.
• FIGS. 15-15C illustratesurgical stapling device10 prior to use. As illustrated,cartridge assembly20 andanvil assembly22 are in spaced relation, trigger16 is in the non-compressed position, and clamp slides66aand66band thrustbar70 are in the retracted position (note pins80aand80bare positioned in the forward end ofslots78aand78bof clamp slides66aand66bandslots102aand102bof thrust bar70). When thrustbar70 is in the retracted position, the forward end of firinglink106 is positioned forwardly ofnotch104 inthrust bar70. Sincelink106 cannot engagenotch104,device10 cannot be fired in this position.Alignment pin pusher68 andalignment pin38 are also in the retracted position withpost94 of bell crank96 engaged in C-clip126 ofalignment pin pusher68. At this point, a surgeon could manually advancealignment pin pusher68 andalignment pin38 by pushing thumb button(s)24 (FIG. 1) towards the forward end ofslots122 formed in body halves12aand12b. This operation would disengage post94 from C-clip126.
• FIGS. 16-16C illustratesurgical stapling device10 during the approximation stroke oftrigger16. As illustrated,trigger16 is moved in the direction indicated by arrow “A” to moveextension115 oftrigger16 in a direction to urgebi-linkage assembly111 from the misaligned position towards the substantially aligned position. Becauserear link114 is secured tobody12 aboutpin113,front link112 extends forwardly.Front link112 is secured to clampslides66aand66bbypin88. Asfront link112 is extended forwardly, clamp slides66aand66bare advanced in the direction indicated by arrow “B” from the retracted position towards the advanced or approximated position. Note the position ofpins80aand80binslots78aand78band102aand102b. As discussed above, rivets117 extend between clamp slides66aand66bthrough103 formed inthrust bar70. As clamp slides66aand66bare advanced, rivet88 engages the forward end ofslot103 formed inthrust bar70 to simultaneously advance thrustbar70. As clamp slides66aand66bare advanced, engagement betweencam slots140 andcam member138 pivots bell crank96 aboutpivot member134 to urgepin pusher68 distally to advancealignment pin38 intonotch30cofanvil assembly22.
• Referring toFIG. 16B, astrigger16 is pivoted in the direction indicated by arrow “A”,cam member180 onextension115 oftrigger16 rides upcam surface176 against the bias of spring174 (FIG. 4). Whentrigger16 is pivoted to advanceclamp slide members66cand66bthrough approximately three quarters of the approximation stroke,cam member180 snaps intocam recess178 to provide an audible and a tactile indication that approximately three quarter approximation has been reached. At this point, the positioning ofcam member180 incam recess178 preventsspring182 from returningtrigger16 to the non-compressed position without activatingrelease mechanism26. Operation of the release mechanism will be discussed below.
• FIGS. 17-17C illustrate thesurgical stapling device10 in the fully approximated position withtrigger16 in the compressed position. As illustrated,extension115 ontrigger16 has been pivoted to movebi-linkage assembly111 to the substantially aligned positioned (slightly over-center position) and clamp slide assembly has been fully advanced such thatcartridge assembly20 andanvil assembly22 are in the approximated position. Once again, note the position ofpins80aand80bwithinclamp slide slots78aand78band thrustbar slots102aand102b. Becausepins80aand80bare located at the proximal end ofclamp slide slots78aand78b, only thrustbar70 can be advanced further distally. If the alignment pin pusher was manually advanced prior to approximation, disengagingpost94 from C-clip126, advancement of clamp slides66aand66bto the fully advanced position moves post94 of bell crank96 back into engagement with C-clip126. Thus, when clamp slides66aand66bare returned to their retracted position,cam slots140 in clamp slides66aand66bpivot bell crank96 in a direction to movepin pusher68 to the retracted position.
• Referring toFIG. 17B, trigger16 has been pivoted to removecam member180 fromcam recess178 in clampingpawl108. Asbi-linkage assembly111 moves overcenter to the substantially aligned position,rear link114 engages abutment member200 (FIGS. 10-11) formed on clampingpawl108 and firingpawl110 to rotate the clamping and firing pawls approximately 10° counter-clockwise. This rotation removescam surface176 from the path ofcam member180 during the return oftrigger16 to the non-compressed position.
• Referring toFIG.17C cam member180′ formed opposite tocam member180 onextension115 oftrigger16 is now positioned abovecam surface190 of firingpawl110. Astrigger16 is released by the surgeon and returned to the non-compressed position byspring182,cam member180′ moves along thebackside190aofcam surface190. Ascam member180′ reaches the bottom edge ofbackside190a,cam member180′ moves over anub220 formed on firingpawl110. Movement ofcam member180′ overnub220 provides an audible click and a tactile indication thatsurgical stapling apparatus10 is in a fire-ready position.
• FIGS. 18-18C illustrate thesurgical stapling device10 in the fully approximated position with thetrigger16 in the non-compressed position. As illustrated, withthrust bar70 in an advanced position, notch104 is now aligned with firinglink106 such that movement oftrigger16 through the firing stroke will effect advancement ofthrust bar70. Referring toFIG. 18C,camming member180′ is now positioned belowcam surface190 of firingpawl110.
• FIGS. 19-19C illustratesurgical stapling instrument10 aftertrigger16 has been moved through the firing stroke. As illustrated, thrustbar70 has been advanced distally to eject staples fromcartridge assembly20. Note pins80aand80bare now positioned adjacent the proximal end ofslots102aand102b. Referring particularly toFIG. 19C,cam member180′ ofextension115 oftrigger16 has moved upcam surface190 and is positioned inrecess192. Engagement betweencam member180′ andrecess192 preventsspring182 from returningtrigger16 to the non-compressed position to provide a visual indication to the surgeon that the surgical device has been fired. Movement ofcam member180′ intorecess192, also provides an audible indication that firing of the device has occurred.
• FIG. 20 illustratessurgical stapling device10 after it has been fired and therelease mechanism26 has been depressed to returnbi-linkage assembly111 to the misaligned position. Oncebi-linkage assembly111 is moved back overcenter,spring71 returns thrustbar70 andclamp slide members66aand66bproximally to returnlinks112 and114 to the misaligned position.
• As illustrated inFIG. 20A,interlock42 is normally urged bypusher assembly54 to a position located withinrecess40. Aftercartridge assembly20 has been fired,pusher assembly54 is no longer positioned to biasinterlock42 intorecess40. Until a new cartridge has been inserted intosurgical stapling device10,interlock42 will extend fromrecess40 to prevent thrustbar70 from being advanced distally.
• FIG. 21 illustratestissue300 having an applied array ofstaples310 formed therein.FIG. 22 illustratestissue300 after it has been bisected with a scalpel (not shown).
• It will be understood that various modifications may be made to the embodiments disclosed herein. For example, the components of the surgical stapling device can be formed of any material suitable for surgical use and having the required strength characteristics. Therefore, the above description should not be construed as limiting, but merely as exemplifications of preferred embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto.

Claims (16)

1. (canceled)

2. A surgical stapling device comprising:

a frame having first and second ends;

a body portion defining a handle;

a trigger supported adjacent the handle;

an anvil assembly secured to the second end of the frame;

a cartridge assembly movably supported in relation to the anvil assembly between spaced and approximated positions; and

means for strengthening the anvil assembly, wherein the strengthening means is supported at the second end of the frame.

3. A surgical stapling device according toclaim 2, wherein the strengthening means includes a stiffener plate.

4. A surgical stapling device according toclaim 3, wherein the stiffener plate is substantially L-shaped, the stiffener plate being secured to the second end of the frame to provide support to the anvil assembly along horizontal and vertical axes.

5. A surgical stapling device according toclaim 4, wherein the frame includes left and right spaced frame sections.

6. A surgical stapling device according toclaim 5, wherein the stiffener plate is positioned between the left and right frame sections.

7. A surgical stapling device according toclaim 2, wherein the stiffener plate is formed of stainless steel.

8. A surgical stapling device according toclaim 2, wherein the frame includes left and right frame sections.

9. A surgical stapling device according toclaim 8, wherein the stiffener plate is positioned between the left and right frame sections.

10. A surgical stapling device according toclaim 9, further including a spacer plate positioned about the stiffener plate between the left and right frame sections.

11. A surgical stapling device according toclaim 3, wherein the stiffener plate includes a slot adapted to slidably receive an interlock, the interlock being movable from a first position to a second position to prevent distal movement of a thrust bar of the stapling device.

12. A surgical stapling device comprising:

a frame having first and second ends:

a handle supported at the first end of the frame;

a trigger supported adjacent the handle;

an anvil supported on the second end of the frame;

a cartridge assembly movably supported on the second end of the frame, the cartridge assembly being movable in relation to the anvil assembly between spaced and approximated positions; and

a stiffener plate supported on the second end of the frame adjacent the anvil, the stiffener plate being substantially L-shaped to provide vertical and horizontal stability to the anvil.

13. A surgical stapling device according toclaim 12, wherein the frame includes left and right frame sections, the stiffener plate being positioned between the left and the right frame sections.

14. A surgical stapling device according toclaim 12, wherein the stiffener plate is formed of stainless steel.

15. A surgical stapling device according toclaim 13, further including a spacer plate positioned about the stiffener plate between the left and right frame sections.

16. A surgical stapling device according toclaim 15, wherein the stiffener plate includes a slot adapted to slidably receive an interlock, the interlock being movable from a first position to a second position to inhibit distal movement of a thrust bar of the stapling device.

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