CA2013054C - Apparatus and method for placing staples in laparoscopic or endoscopic procedures - Google Patents

Abstract

A surgical stapler for placing lateral lines of staples and making an incision, all through an endoscopic tube, includes an anvil member which is mounted to the distal end of an elongated housing. A tubular collar disposed around the arm of the anvil member is movable to a distal position to bias the anvil member and a cartridge assembly into cooperative alignment, thereby clamping body tissue to be fastened between the anvil member and cartridge assembly.

Description

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203-1 5~ (~ 1 04) APPA~ATUS AND MET~30D FOR PLACING
STAPLES 1~ LAPAPOSCOPIC OR ENDOSCOPIC P~OCEDURES

BACKGROUND OF THE IN~ENTIOI~

1. Field of the In~ention This invcntion relatcs to surgical stapling apparatus, and more particularly to a surgical stapler for mechanically effecting a plurality of lincs of stitching staples iD body tissuc.

2. Background of Rclated Art In some surgical operations it is neccssary to adjoin two hollow body organs alongside each other, gcnerally with thcir longitudinal a~es parallel to cach other, and to effcct a longitudinal cut through the contacting circumferential walls of the two organs so that ~he two OrgaDS constitute a single hollow chambcr along the Icngth of the cut. Cor-espondiDgly, thc circumfercntial portions of the two adjoining organs on cach latcral side of the cut must bc sutured by at least oneline of "stitches" in order to maintain thc intcgrity of the union.

Instruments for this purpose can comprisc two elongated fingers which are respcctively inscrtable into each organ from an opcn cnd thereof, the two fiDgers thereby having bctwccn them thc two adjoi~ling walls of the organs. Typically, one of thc fiDgcrs carrics a disposablc cartridge housing a plurality of staples arranged in at least two lateral rows while the othcr finger compriscs sn anvil for curling the staple lcgs into hook form upon thcir being driven against the anvil.
Thc stapling opcration is cffected by a pushcr which travcls longitudinally along the cartridge carrying fingcr c~tending into one organ, with thc pusher acting upon thc staplcs to place rows of staples in body tissue. Immcdiafcly behind thc pusher and laterally positioned between the staple rows is a knife which severs the facing adjoining walls of the two organs to thereby longitudinally open thc two organs to each other between the rows of staples.

One such instrument is discloscd in Bobrov et al. (U.S. Patent No.

3,079,60Q The instrument discloscd therein comprises an apparatus for simultaneously making 8 lon~itudinal incision and applying a row of staplcs on both sides of the incision. A further improvement is disclosed in Green (U.S. Patent No.
3,490,675).

A later development disclosed in Green (U.S. patent No. 3,499,591) applies a double row of staples OD each side of the incision. This is accomplished by a cartridge asscmbly wherein a cam member movcs within a guide path between two sets of staggered staple carrying grooves. Staple drive members located within the grooves each have two staple pusher plates, and sloping surfaces disposed withinthe guide path so as to be contactcd by the longitudinally moving cam and be driven along the groove to cffect ejection of two staples.

These above-mentioned instrumcnts comprise upper and lower frames which must be assembled before use, and disasscmblcd after use. Such instruments have been uscd successfully in surgical operations rc~uiring the placement of gastrointestinal anastamosis, but they require the surgeon to have direct manual access to the operation site.

Howcver, in laparoscopic procedures surgery is performed through a small incision, and in cndoscopic procedures surgery is performed througb narrow endoscopic tubes inscrte~ through small entrance wounds in the skin. Up to now thcre havc becn no instruments for placing lateral staple lincs in laparoscopic or endoscopic proccdurcs. Nor has thcre beeD any instrument suitable for placing lateral lines of staples aDd cuttin~ tissue therebetween in laparoscopic or endoscopic procedurcs.

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Because endoscopic procedures are more common than laparoscopic procedures, the present invention shal] be discussed ;D terms Or endoscopic procedures and apparatus. However, use herein Or terms such 85 ~endoscopic~, ~endoscopically" and "endoscopic portion~, among others, should not be construed to limit the presentinvention to a stapling and cutting apparatus for use on!y i~ conjunction with an endoscopic tube. To the contrary, it is believed the preSeDt invention may find use in any procedure where access is limited to a small incision, including but not limited to laparoscopic procedures. Also, as used herein the terms ~fasteners~ and ~staples~ shall be treated equivalently. Unless otherwise stated, the term "cartridge assembly" shall include at least the cartridge itsclf ana staples or fasteners and staple drive members disposed therein.

3. Objects of the Invention Accordingly, it is one object of the present invention to provide a surgical stapling apparatus.

It is anothcr object of the present invention to provide a surgical stapling apparatus which can adjoin hollow body organs alongside each other.

It is yet a further object of the present invention to provide a surgical stapling apparatus which can be used endoscopically.

Another objeet of the present invention is to provide a surgical stapling and CUttiDg apparatus which ean be used endoseopieally.

These and further objects and advaDtages are achieved by providing a surgical stapling apparatus insertable through a small incision or narrow tube for dri~ing surgical fasteners into body tissue and eutting the body tissue between rows of staples.

2 ~ L ~,t ~ ~, ' t, SUMMARY OF THE INVENTION

In accordance with the present invention a surgical stapling apparatus is provided for placing one or more rows of staples endoscopically. Advantageously, a stapler apparatus constructed in accordance with the invention may further include a knife for making an incision in body tissue between rows of staples. The latter eonfiguration may fiDd particular use in adjoining two hollow organs or in removing an organ, such as the appendi~c.

Briefly stated, the surgical stapler in accordance with the invention comprises:

a) a frame;
b) a tubular portion defining a longitudinal a~is and e~tending distally from said frame, said tubular portion including:

i) an elongated housing having means for mounting a cartridge assembly, said cartridge assembly including a plurality of surgical fasteners mounted therein, and having a tissue engaging surface;
iii) an anvil member having a fastener forming surface, said anvil member mounted to said elongated housing;
iii) means for effecting relative movement between said cartridge assembly and said anvil member; and iv) means for ejecting said surgical fasteners from said eartridge assembly, whereby said fasteners engage said fastener forming surfaee.
In one ~mbodiment of the invent;on the frame and endoscopic pOrtiOD of the instrument are reusable with replaceable staple carrying cartridges.

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In another embodimen~ of the invention the endoscopic portion is formed as a disposable unit detachable rrom a reusable handle portion including the frame.

In yet a further embodiment of the invention, the entire i~strument may be constructed as a single-use, dispGsable unit.

Aeeording to the method of the present inveDtion, the endoscopie portion of the apparatus is inserted into the body through a small ineision or, more likely, through an endoscopic tube. With the anvil member in the open position, body tissue is disposed between the anvil member and the tissue engaging surfaee of the cartridge assembly. The anvil is then closed against the eartridge to clamp the body tissue between the anvil and cartridge. The instrument is fired so that staples ejected from the cartridge penetrate through the body tissue and are formed closed against the anvil. Where appropriate, a knife forms an incision between several rows of staples. Aîter the instrument has been fired, the clamping action of the anvil and cartridge assembly is released and the endoscopic portion of the instrument is withdrawn from the body.

The present invention advantageously perrnits a surgeon to perform internal stapling and eutting procedures without full access to the stapling site. Surpr;singly, the staplin8 and eutting instrument in aceordance with the invention may be inserted through a small ineision or tube in order to place multiple staple lines and make an incision in the stapled tissue bet~veen several rows of staples.

The ability to perform stapling and eutting procedures through a small ineision or tube remarkably reduces blood loss, tissue trauma and patient reeovery time, eontributing to improved health eare praetiees.

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BRTEF DESCRIPTION OF THE DRAWINGS

Fig. I illustrates 8 perspective cutaway view of the invention;
Fig. 2 il]ustrates an e~ploded view of the frame;
Fig. 3 illustrates an c~ploded vicw of the toggle Iever actuating mcans;
Fig. 4 illustratcs aD e~ploded view of the interior actuating means;
Fig. 4A illustrates a sectional side view of the collar pivot holder, collar pivot support, collar pivot wheel, channel pin holder and channel pivot;
Fig. 5 shows the tubular covcr;
Fig. ~A illustrates thc connection bctwcen the cover and thumbwhecl;
Figs. 6 and 7 show the collar shaft and collar;
Figs. 8 and 9 illustrate the cam bar channel, cam bars, knife and cam bar adapter;
Figs. 10 and 11 illustrate the housing and anvil;
Fig. lIA illustratcs a sectional view of the housing and collar;
Fig. 12 illustrates an e~ploded view of the cartridge, staple drive member and staplcs;
Fig. 13 illustrates a side view of the cartrid~e;
Fig. 14 illustratcs the surface of the cartridge which comes in contact with body tissue;
Figs. 15A and l5E3 ;llustrate thc clamping action of thc instrument;
Fig. 16 illustrates a thrce staple drive member that can bc uscd with the preSeDt invtntion;
Fig. 17 illustrates a sectioDal view of the cDdoscopic portion of the instrument in accordance with a first alternative embodiment of the invehtion;
Fig. 18 illustrates a s;de view of the collet in accordancG with the first altcrnative embodiment of the invCDtiOn;
Fig. ]9 illustrates is a pro~timal end Yiew of the eollet of Fig. 18;
Fi~. 20 illustrstes a seetional sidc ~icw of thc slcevc in accordance with the first alternative embodiment of the iDventioD;

Fig. 21 illustrates a top plan view of the clamp tube of the firs~
alternative embodiment of the inveDtion;
Fig. 22 illustrates a top plan view of the elamp tube snap of the first alternative embodiment of the invention;
Fig. 23 illustrates a side view of the channel adaptor of the first alternative embodiment of the invention;
Fig. 24 illustrates a scctional s;de view of a handle and frame portion in accordance with the first alternative embodiment;
Fig. 25A illustrates a scctional view of the frame in accordaDec with the first alternativc embodiment;
Fig. 25B illustrates a distal end view of the frame half illustrated in Fig. 25A;
Figs. 26A and 26B illustrate side and distal end views, respectively, of the inner handle of the first alternative embodiment;
Figs. 27A, 27B, 27C, 27D and 27E illustrate bottom plan, front side, sectional front side and two partial rear side views, respectively, of the frame clamp tube;
Figs. 28A and 28B il]ustrate top and front Yiews, respectively, of a frame Ieaf spring;
Fig. 29 illustrates a sec~ional side view of the outer tube of the first alternative embodiment;
Fîgs. 30A and 30B illustrate side and distal end views, rcspectively, of the outer handle of the first al~ernative embodiment;
Fig. 31 illustrates a side view of a drive tube in accordanee with the first alternative embodiment; and Figs. 32A and 32B are top plan views of the framc elamp tube, drive tube and Ieaf spring illustrating pro~imal snd distal frame elamp tube positions.

2 ~ ~ ~? ~,~ . s DETAILED DESCRiPTlON QF THE PREFERRED EMBODIMENTS

The surgical apparatus deseribed herein includes a frame and handle portion supporting an endoscopic portion, i.e., an e~tended tube-like portion having a relatively narrow diameter, o~ the order of about 10 millimeters, for insertion into a small opelling in or tube inserted into the body, sueh as in the sbdominal eavity. The endoseopie portion defines a longitudinal aais and has a length appropriate for reaehing the operation site in the interior of the body. The apparatus may be used in eonjunetion with endoseopes (devices for visually e~amining the interior of the body, for e~ample, by means of fiber optics). The endoscopic portion of the apparatus is inserted through the small opening or wound, manipulated to the operation site, and the instrument is actuated. The endoscopic portion has a fastening and cutting portion including an elongated housing whieh carries a fastening and cutting portion to the operation site. The fastening and cutting portion ineludes jaws defined by a staple earrying eartridge (typieally loeated at the distal end of the housing), an anvil and further includes a knife. Actuating the operating portion must be aecomp]ished via intermediate components disposed on or within a narrow longitudinally e~tending tubular structure. The bulk of the primary operating components are housed on or within a frame, which is located outside the human (or animal) body being operated upon.

The instrument of the present invention has three basie sctions or functions.

First, the endoscopic portion is introduced into the body ant positioned with the jaws aligned at the stapling site to reeeive the target tissue. This may involve rotation of the endoseopie portion relative to the body, either by rotating the stapling instrument, as a whole, by rotating the endoseopie portion relative to the frame as permitted in the preferred embodiments, or a eombination of both aetions.

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Second, the instrument has a means for securing the targct body tissuc between the cartridge assembly and the anvil. This is accomplished by a clamping action. With thc target tissue clamped between the anvil and the cartridge assembly, a camming means which surrounds the housing and anvil member is employed to closc the jaws of the apparatus and clamp the tissue between the anvil and the tissue contacting surface of the cartridge.

~ hc third action is that of applying the staples to the body tissue. A
longitodinally c~ctending channel is employed to deliver longitudinal motion to pusher cam bars and a tissue cutting knife. The cam bars contact pushcr elements which drivc the staples through the body tissue against the fastener forming or forming surfacc of thc anvil. After the instrument has been fired, the clamping action of the jaws is released and the instrument may be withdrawn from the body. The following details will provide an in-depth understanding of the various elements, operations and functions of the present invention.

Fig. 1 shows a cutaway pcrspectivc view of the instrument of the present invention 100, which generally comprises a frame 102 supporting an endoscopic portion 103, means for actuating the instrument to clamp body tissue, and means for firing the instrumrnt to drive staples into the body tissue and form an incision in the tissue between s~aple rows.

More particularly, referring now to Figs. 1 and 2, frame 102 has two parts: a Icft portion 102L and a right portion 102R. These portions are optimally fastened togcthcr by means of fastening screws 101, although rivcts, wclds or other means of joining the two frame parts may also be uscd. The left portion 102L has a vertical clongated slot 102A to allow access to a thumbwheel 123 (See Figs. 1 and 4). ~rame 102 is elongated and has a~ interior surface defining a distal opening 102B, pro~imal open;ng 102C, an interior distal cylindrical chamber 102D, an interior pro~cimal cylindrical chamber J02E, a circumfcrential thumbwheel mounting groove 102H, an upper guideway 102F, and a lower guideway 102G. The frame is of an overall size and shape convcnicnt for being held in the hand.

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Referring additionally now to Fig. 3, togglc lever 104 transfers motion to the toggle links discussed below and thereby provides a means to activate the clamping action of the apparatus in responsc to manual prcssure from the surgeoD or other operator of the instrument. Toggle Icver 104 is an elongatcd piece having a distal end pivotally mounted in pro~imity to the distal end of the frame by means of lever pivot pin 105, which is disposed through transversely sligned aperture 104B in the distal end of the togglc lever 104.
Toggle lever 104 fur~her has a pro~imal end pivotally connected to toggle link 107 by means of toggle link pin 106 which is disposed through aperturc ~04A in the toggle lever. In response to pressure, the toggle lever 104 rotates around the a~is dcfined by toggle lever pin 105, and transfers movement to the toggle links.

Toggle link 107 is an elongated mcmber having a rounded first end with fork member 107A, which defines a longitudinal slot 107C, a transversely aligned aperture 107B for receiving togglc link pin 108, and a backstop surface 107D. Thc rounded sccond end of toggle link 107 has a transversely aligned apcrture 107E for receiving toggle link pin 106. Toggle link 107 transfers movement from the toggle levcr to toggle link 109.

Toggle link 109 is an elongated relatively thin, flat piece having a rounded first end with transversely aligncd aperture 109~ for receiving pin llû, and a partially rounded second end having transversely aligned aperture ]09B for rcceiving toggle link pin 108, and a rotation limiting member 109C.

Thc first end of toggle link 109 is mountcd in slot lllA of the collar moving pivot 111 by means of pin 110 which is disposed through aperturc IO9A.
The second cnd of togglc link 109 is piYotally mounted in slot 107C in the fork member 107A of toggle link 107 by means of pin 108. Rotation limiter lO9C is a flat angular member projecting pro~imally from the second end of the toggle 2 ~

link 109. Thc rotation limiter is adapted to abut the correspondin8 backstop surfacc 107D in toggle link 107 such that thc joint betwcen ~oggle ]inks 107 and 109 is prevcnted from further bending in the distal direction. The rotation limiter 109C thus acts as a locking feature, prevcnting the toggle lever 104 from being depressed, snd thereby preVentiDg the clamping function to bc actuated. WheD the coupling is bent in the pro~imal direction, however, the toggle Icver 104 can be fully depressed so as to actuate the apparatus by movingcollar moviDg pivot 111.

Collar moving pivot 111 is a substantially rectaDgular shaped piece slidably mounted in the upper guideway 102F of the frame 102. Collar moving pivot has a longitudinal slot IIIA and a transversely aligned aperture lllB in proximity to the distal end of the collar proving pivo~. The slot IIIA is for receiving the first end of toggle link 109, and thc aperture lllB is for receiving pin 110 for pivotally mounting said toggle link 109. Collar moving pjvot 111 has a depending plate II]C, which has a relatively wide spacer portion IIIE aDd transversely aligncd aperture IIID for receiving pin 113 (Fig.
4).

Depending portion llIC is mountcd in slot 112B of thc collar pivot holder 112 (Fig. 4). Pin 113 disposed through aperture 112C in the collar pjvot holder and IllD in the collar moving pivot, links these two pieces.
Collar moving pivot 111 provides a means to convert the rotational motion of thc toggle links to linear movement in the longitudinal direction.

Referring additionally to Figs. 4 and 4A, collar pivot holder 112 is a substantially cylindrica] piece which is locatcd below thc collar moving pivot 111, and which is slidably mounted in tlle vro~imal cylindrical chamber 102E.
Collar pivot holder ]12 has a distal end with an internally threaded a~ial hole 112A, and a pro~ima1 end with a longitudinal slot 112B for receiving depending plate 111~ of the collar moving pivot, and transverse aperture 112C adapted to receive pin 113 for mounting the depending platc IIIC.

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Collar pivot holder 112 provides a means to transmit longitudinal movement from the collar moving pivot to the collar pivo~ wheel 115, which is connected by means of thc collar pivot support J14.

Collar pivot support 114 has a longitudinally projecting threaded bolt por~ion 114A aC its pro~imal e3~d for mounting into the hole 112A of the collar pjvot holder 112. At its distal end, eollar pivot support has 8 longitudinally projectin~ pin 114B with 8 eircumferential notch 114C for engaging E-ring setainer 116. Pin 114 is disposed through a~ial aperture II~A of the collar pivot wheel 115, and ~he distal end of the pin with notch 114C projects out through the distal end of said aperture llSA where E-ring retainer 116 is clipped onto said notch thereby maintaining collar pivot wheel 115 on pin 114B. Collar pivot support 114 not only provides a means for connecting collar pjvot wheel 115 and collar pivot holder 112 so that longitudinal motion may be transferred, but also provides an a~is (pin 114B) around which collar pivot wheel IIS may freely rotate.

Collar pivot wheel 115 is a substantially cylindrical piece slidably mounted in the proximal cylindrical chamber 102E of body 10Z. Concentric aperture 115A e~cte~ds from the pro~imal to distal end of said collar pivot wheel f3r receiving pin 114B. Collar pivot wheel 115 further has eccentric hole 115B ;D its distal end for receiving mounting bolt 125A Or the collar shaft 123 (Fig. 6). Collar pivot wheel IIS is movable both longitudinally within pro~timal cylindrical chamber 102E, and rotationally around pin 114B.
Collar pivot wheel llS transfers longitudinal motion to the eollar shaft 125 for the purpose of elamping the jaws of the apparatus.

Channel pin holder 121 is a substantially eylindrical shaped piece slidably mouDted in the distal eylindrieal ehamber 102D, and having a hollow a~tial interior. At its distal end, channcl pin holder has a male snap-in plug 121A with eontraction slots 121B for mounting into the pro~imal end of ehannel pivot 122. Channel pin holder 121 is mountable by means of serews 120 oDto firing support shaft 1]9 and provides a means for transfcrring longitudinally movement from the firin8 support shaft 119 to thc channcl pivot for the purpose of firing thc surgical fastencrs. Channel pin holdcr 121 movcs only lon~itudinally. The snap-in plug 121A scrvcs as an a~cis around which thc channcl pivot 122 may rotatc.

Firing support shaft 119 is sn elongated substantially rectangular picce slidably mountcd ;D thc lowcr guidcway 102G. Concavc surface portion 119A at thc distal end of the firing support shaft 119 is for mounting the channcl pin holder 121, aDd has a curvature correspoDdins to thc outside surface of the channel pin holder 121. Screws 120 are disposed through transverse apertures ll9C in the firing support shaft 119, and into holes in the bottom of channel piD holder 121 for mounting said channcl pin holder 121 to thc firin8 support shaft 119. At its pro~timal end, firing support shaft 119 has a longitudinally c~tending threaded hole !]9B for rcceiving threaded screw portion 118A of the plungcr 11 8.

Firing ~upport shaft transfcrs longitudinal movement from the plunger 118 to the channcl pin holder 12] for firing thc fastencrs.

Plungcr 118 is a rod having thrcadcd screw mounting portions at both the distal and pro~imal ends. The distal scrcw portion 118A is for mounting to thc thrcaded hole 119B ;D the firing support shaft 119., Thc pro~imal scrcw portion 118B is for mounting a push button 117 by mcans of central threaded aperturc 117A in the push button. The plunger rod e~tcnds pro~imally outsidc the pro~imal OpeniDg 202C in thc body 102.

Channcl pivot 122 is a substantially eylindrical piece located wi~hin ~hc distal eylindrical chambcr 102D of framc 102. At its pro~imal end, ehannel pivot 122 has opcning 122~ to servc as a rcccptacle for snap-in portion 121A of the eollar pin bolder 121 upon whieh the channcl pivot 122 is rotatably mounted. As can be scen from Fig. 4A, rcceptacle portion 122C has 8 -~ - 2 0~

circumferential lip 122E to interlock with the snap-in portion 121A. At its distal end channel pivot 122 has a stud 122A for mounting the pro~imal end of cam bar ehanoel 129 (Fig. 8). Mounting screw 128 is disposed through transverse aperture 122D to secure the eam bar channel 129. Collar shaft 125 is disposed through aperture 122B.

Channel pivot 122 provides a means for transferring longi~udinal movement from the ehannel pin holder 122 to the eam bar ehanncl 129 for the purpose of firin8 the surgical fasteners. Channel pivot 122 also provides a means to rotate the cam bar channel 129 and collar shaft 125 around the longitudinal a~is of the instrument.

Thumbwheel 123 is disk shaped piece rotatably mounted in the circumferential thumbwheel mounting notch 102H. Thumbwheel 123 has a distally extending eylindrical projection 123B, rectangular slot 123A, detents 123C
transverse to slot 123A, projecting distally from the eylindrieal projeetion 123B, and a eireumferential surfaee 123D whieh partially projects through elongated noteh 102A. Thumbwheel 123 ean be rotated by manually applying a turning foree to the portion of the eireumferential surface IZ3D whieh projeets through the elongated notch. Upon being rotated thumbwheel 123 will thereupon turn the eover, eam bar channel, collar shaft, around the longitudinal a~is of the instrument for the purpose of imparting rotation to the endoseopie portion of the apparatus distal to the frame.

Referring additionally DOW to Figs. ~ snd SA, eover 124 is a relatively long tubular pieee having a diameter appropriate for use in endoscopic surgical proeedures and projeeting distally through the distal opening 102B of the framc in alignment with the longitudinal a~is of the instrumeDt. At its pro~imal end, eover 124 has a flange 124A whieh has notches 124B to eooperatively engage detents 123C of the thumbwheel 123. Flange 124A is mounted flush against cylindrieal projection 123B of the thu~bwheel. Cover 124 is rotatably mounted as to turn in conjunction with the rotation of the thumbwheel. Collar shaft 125 and cam bar chanDel 129 e~ctend longitudinally through thc intcrior of the cover 124. Cover 124 provides a means for enclosing the collar shaft 125 and cam bar channcl 129 to prevcnt them from contacting e~traneous body tissuc while the instrument is bein8 uscd.

Rcferring additionally to Figs. 6 and 7, collar shaft 125 is a relatively long rod in parallel alignment with the longitudinal a~is of the instrumcnt aDd havi~g a pro~imal cnd with a threaded screw portion 125A for mounting to the collar pivot whecl 115, as discussed above, and a distal end with a screw portion 125B for mounting to the tapped hole 126A in collar plug 126. Via collar plug 126, collar shaft 125 transmits longitudinal motion to the collar 124 for the purpose of closing the jaws of thc instrument to secure the target body tissue. Collar shaft 125 moves longitudinally, and it may be turned around thc instrument a~is although it does not rotatc relative to its own a~is.

Collar plug 126 provides a means for connecting collar shaft 125 to collar 127. Collar plug 126 has a thrcaded aperture 126A for mounting screw portion 12~B of the collar shaft 125, and distal radial projections 126 which mount in circumfcrential slots 127A in the collar 127.

Collar 127 is a substantially tubular piece located distally to thc covcr 124 and aligned with the longitudinal a~tis of the instrument. Collar 127 has circumferential slots 127A in proximity to thc pro~cimal end of thc collar 127, and a distal cqmming edgc 127B. As seen ;D Fig. ISA, distal camming edge ]27B pro-~idcs a means for closing the jaws of the instrument to securc the tar8et body tissue. This is discusscd in more dctail below.

Referring sdditionally now to Fig. 8, cam bar channel 129 is an cloDgatcd piece ha~ing an inverted U-shaped cross section and which is slidably mountcd in housing 134. At its proxirnal end, cam bar channel 129 has a 2 ~ ~ 3 ~

transverse aperture 129D for receiving fasteniDg screw 128. The pro%imal end of the cam bar channel 129 is mounted to the rectangular mounting stud 122A of ehannel pivot 122 (Fig. 4). At its distal end, eam bar ehannel 129 has a gripping fork 129B and slot 129A. Gripping fork 129B and slot 129A provide a means of engaging and holding eam bar adapter 130. Longitudinal notches 129C
allow the cam bar channel to move without interference from anvil pivot pin 135 (Fig. 11~, as discussed below. Cam bar ehannel 129 transm;ts longitudinal motion from channel pivot 122 to the eam bars 131 and kDife 132 for performing the tissue fastening operation.

Referring to Figs. 8 snd 9, eam bar adapter 130 is mounted to the gripping fork 129B of the cam bar ehannel 129 and provides a means for holding the cam bars 131 and knife 132. Cam bars 131 are parallelly and longitudinally aligned. Their pro~imal ends are mounted in the longitudinal slots 130A of cam bar adapter 130. Knife 132, parallelly and longitudina}ly aligned wi~h cam bars 131, is also mounted to 8 slot 130A in the eam bar adapter 130. Knife 132 has a eutting ed8e 132A on its distal end.

Referrin8 additionally now to Figs. 10, 11, and llA housiDg ]34 is an elongated piece which is aligned with the longitudinal a~is oî the instrument.
Housi~g 134 has a pro~imal end mounted to the eylindrieal projection 123B of thumbwheel 123 by means of pin 133 (Fig. 5). At its distal end, housing 134 has a relatively wider seetion 134B for engaging and holding a cartridge assembly 137. Transverse aperture 134C receives anvil pivot pin 135. Housing 134 also has a longitudiDally e%tending center guide rail 134A arouDd which eam bar ehannel 129 is slidably mounted.

Anvil member 136 is an elongated pieee which is pivotally mounted to the housing 134. At its distal end anvil member 136 has sn anvil plate 136A with a tissue eontaeting surface 136E with staple forming depressions 136D (see Fig.
13). Anvil member 136 eomprises arms 136B and, at the pro~imal end, a hinge 3 "

136C for pivotal mounting to housing 134 by mcans of anvil pivot pin 135 disposcd through the hinge 136C and aperture 134C. Anvil member 136 is rotatable between an open position (see Fig. 15A) and a closed position (see Fi8. ~5B) whcrc the anvil forming surface is brought into close cooperative alignment with the cartridge sssembly 137. Anvil platc 136A also has a longitudinal ccntcr groove 136F to permit passagc of knife 132. Anvil mcmber 136 provides ODC of the jaws of the instrument for clampin8 and securing the body tissue to be fastened. Prsferably, anvil 136 is provided with one or more tissue stops 140 which engage corrcsponding depressions, opcnings or indentations in housi~lg 134 (ses Figs. 11, 15A). Tissue stops 140 help prevent oYcr-insertion of tissuc into the jaws.

Referring additionally now to Figs. 12, 13 and 14,the cartridge assembly comprises a cartridge 137 with alignment plate 140, pusher clements or staple drivers 139, and surgical fasteners or staples 13R. The staples 138 and pushers 139 are disposed within grooved slots 137A such that as the cam bars 131 move distally a~d longitudinally through the cartridgc 137, pushers 133 are driven up through the grooved slots 137A driving staples 138 through the body tissue layers 201 and 202 which arc to be joincd, and into snvil plate 136A
wherc the legs of the staples are crimped in staple forming deprcssions 136D.
Alignment plate 140 serves as 8 cover to kecp the staple drivers aligned within cartridge 137. Preferably, cartrid8c 137 contains two rows of stapl~ pusher elements, with each staple pusher element acting on three staples. One such staple pusher element 139 is illustrated in Fig. 16. Tbe preferred staple drive member thcre illustratcd includes a body portion 600 having a distal cnd 602, a pro~imal end 604 with at least one camming surface 606, and thrce substantially rcctangular pusher plates 608, 610, 61Z aligned in the direction of cam motion. Pushcr platcs 6U8, 610 are laterally aligned on either side of body portion 600 and havc an cnd coterminous with the body portion pro;~imal end604. The middlc pusher plate 612 has ~n end coterminous with the body portion distal end 602. None of the pusher plates e~tend the full length of the body portion. Preferably, each pushcr platc also includes guide rails 614 and a staple cradling notch 616. Guide rails 614 are received by and slide in corresponding slot portions of thc cartridge. As shown in Fig. 16, cach staple drive mcmbcr is prcfcrably driven by a doublc cam bar.

~ Fig. 14 illustrates ~he surface of the cartridge 137 v~hich comes in eontact with body tissuc. Grooved slots 137A tcrminate in openiDgs through which the staples 138 are ejected. Groove 137B guides the movcment of knife 132 through the cartridge.

As will be appreciated from the layout of slots or grooves 137A shown in Fig. 14, the preferred arrangement iDcluding two rows of staple drive members, each acting on thrce staples, results in si~ rows of staples with three overlapping staggered staple rows on each side of knife groove 137B. Placing three staggcrcd ovcrlapping rows of staplcs on cithcr side of ~hc incision obtains improvcd tissue holding strcngth and hemostasis.

A first alternative embodiment of the iDvention is illustrated in Figs.
17 - 31. In the cmbodiment there shown thc cndoscopic portion 300 of thc instrumcnt is dctachable from thc frame and handlc portion 301 of the instrument (see Figs. 17 and 24). Fndoscopic portion 300 preferably eonstitutes a disposable unit, thc frame and handle portion of thc instrument bein8 rcusablc with replaccment endoscopic portions.

- Refcrring now to Fig. 17, a scctional side Yiew of cndoscopic portion 300, the endoscopic portion has a housing 324 mounted st the pro~imal end to a collet 402. At thc distal cnd of thc endoscopic portion~ housing 324 supPorts a cartridge housirJg 334 and an anvil 336. In this cmbodiment, a clamping tube 327 has a clamping pOrtiOD 327A of substantially thc same outcr diameter as housing 324, a tapered section 327B, and a shaft portion 327C having a narrow diameter configured snd dimensioned to slide a~ially withiD bousing 324~ The pro~cimal cnd of the narrow diamcter shaft section 327C is fi~edly mountcd to a elamp tube snap 404. ~ cartridge 337 is mounted to cartridge housing 334 and engages eam bars 33] and a knife 332. As shown in Fig. ]7, cam bars 331 preferably are staggered longitudinally relative to one another in order to improve the balance of forces generated in driving the preferred three staple drive members to eject three staggered parallel rows of staples on either side of the incision formed by knife 332. Similar to the first described embodiment, eam bars 331 and knife 332 engage and are supported by a eam bar adapter 330 which, in turn, engages the distal end of a eam bar ehannel 329.
The proximal end of cam bar channel 329 is fi~edly mounted to a channel adaptor 406.

As shown in Figure 18, collet 402 is substantially cylindrical in shape ha~ing a cylindrical support section 408 at the dista] end thereof and a plurality of collet fingers 410 extending longitudinally in she pro~imal direction. Each eollet finger 410 has an outwardly projecting midsection portion 412 with an inclined surface 414 projecting a~ially inward in the pro~cimal direction. Each collet finger also has an outwardly projecting pro~imal flange portion 416 terminatin~ at an inclined surfaee 418 eItending axially inward in the proximal direction.

Figure 19 is a pro~imal end view of eollet 402, illustrating si~ collet fingers 410 configured as sections of a cylinder. Collet 402 and, more specifieally, collet fingers 410 are preferably made of plastic and may be fle~ed inwardly from their normal, or rest position. Fingers 410 have memory and returD to their rest position when the fle~ing foree is reieased.

The inner diameter of eylindrical support seetion 408 is eonfigured to accept the pro~imal end of housi~g 324. The pro~imal end of housing 324 is fi~ed to eylindrical support seetion 408 by any appropriate means, iDeluding but not limited to frictioD fit and/or eDgagement of onc or more projections or ribs 420 on the inner surface of cylindrical support sectiorl 408 (see Fig., 19)with eorresponding openings or slots on the housing 324.

" ~3 Referring again to Fig. 17, collet 402 is disposed within and engages an outcr slceve 422 sueh that sleeYe 422 is rotationally immovable relative to the collet but is longitudinally movable relative to the eollet with a limited range of motion. As shown more particularly in Fig. 20, sleeve 422 has an outer gripping surface including a gripping ring 424. Sleeve 422 has a distal portion 426 iDeluding an inwardly estending longitudinal rib 428 which engages a longitudinal slot 430 on the outer surface of the collet cylindrical support section 408 (see Fig. 19). As ~ill be apparent, engagemeDt of rib 428 and slot 430 preven~s rotational movement of the sleeve 422 relative to the collet and ~ice versa. Sleeve 422 also has an inwardly projecting flange 432 at the sleeve midsection. Flange 432 has an area 434 of minimum diameter which corresponds to and engages the outer diameter surface of collet fingers 408 between outwardly projecting flanges 412, 416 (see Fig. 17). Flange 432 also has an inclined surface 436 projecting al~ially iDward in the pro~imal direction. Inclined surface 436 substantially corresponds to and engages inclined surface 414 on collet fingers 410 (see Figs. 17 and 18). In order to limit the range of longitudinal motion of sleeve 422 relative to eollet 402, proximal and distal limiting stops 438, 440 are provided. Pro~imal limiting stop 438 engages the distal flat surface of the outwardly projecting midsection 412 of one or more collet fingers 410, thereby limiting longitudinal motion of the sleeve in the prosimal direction. Distsl limiting stop 440 abuts the pro%imal flat surface of collet eylindrical support section 408, thereby iimiting the longitudinal motion Or the sleeve in the distal direction.

Between these two e~treme positions, limited longitudinal motion of the sleeve in the distal direction from the position illustrated in Fig. 17 is permitted, such that inelined surfaces 414, 436 exert a~ially inward foree on eollet fingers 4lO. In this manner, eollet fingers 410 and, more partieul~rly, the proximal ends of eollet fingers 410, may be flexed inwardly from their rest or memory position for reasons to be diseussed hereinafter.

2 ~

The pro~imal section 442 of slceve 422 has an inncr diamcter which is configurcd and dimcnsioned to accept and surround a corresponding outer tube projection on the framc with uncDcumbercd rotational motion bctween thc slecvc and the frame.

Referring agail~ to Fig. 17, radial housing support pins 444 c%tcnd through the cylindrical interior of housing 324 near the distal end thercof.
Pins 444 e~tend through longitudiDal slots 446 on clamping tube 327 (sce Fig.
21~ and a similar slot iD channcl 329 (not shown). The pro~imal end of eartridge housing 334 is fi~edly mounted to housing 324 by ho~sing support pins 444. At thc distal end, cartridge housing 334 supports cartridge 337. Housing support pins 444 also affi~c the pro~imal end of an anvil leaf spring 448 to housing 324. The distal end of spring 448 supports anvil 336. As shown in Fig. 17, anvil spring 448 acts as a leaf spring to bias the anvil into the open position there shown.

Preferably, at least onc pair of corresPonding anvil alignmcnt guidcs, shown as alignment pin and slot 450, 4~2, are providcd on thc anvil and cartridgc. Alignmcnt guides 4~0~ 452 cnsure proper alignment of the anvil and cartridge tissue contacting surfaces so that staples cjected from the cartridgc accurately cnga~c corresponding staple forming grooves in the anvil. Also prcferred are one or more tissue stops 4~4 to cnsure proper placement of the body tissue bctwcen thc jaws without ovcr-inscrtion of the tissue bcyond thc tissue contacting surfaces of thc anvil and cartrid8e.

Clamp tube 327 surrounds thc pro~imal portion of the an~il, anvil spring snd cartridge housing in a manncr similar to the first describcd embodimcnt, and movcs longitudinally betwecn the open position shown in Fig. 17 to a distal, elosed position elamping thc uppcr jaw closcd against thc lower jaw (sce Fi~s. 15A and 15B). In the latter position body tissue is clampcd betwccn thc aDvil and cartridgc in thc manncr illustratcd in Fig. 13.

2 ~

As shown in Figs. 17 and 21, clamp tubc 327 has a clamping portion 327A
with an outer diametcr substantial1y thc same as housing 324. At the pro~cimal end of clamping portion 327A clamp tube 327 has a tapered scction 327B which joins clamping portion 327A to narrow diameter shaft portion 327C. Clamping port;on 327A and shaft portion 327C are substantially cylindrical. Shaft portion 327C has an outer diamcter smaller ~han thc inncr diameter of cylindrical housing 324, thereby permîtting longitudinal movemcnt of the clamping tubc relative to thc housing. As shown in Fig. 21, shaft portion 327C
includes longitudinal slots 446, 456. As previously described, housing support pins 444 c~tend through slots 446. It will be noted that slots 446 arc configured to permit sufficient longitudinal movement of clamp tube 327 and channel 329 relative to housing 324 to close thc instrument jaws and fire the instrument. Pins 444 isolate the anvil and cartridge housing assemblies relative to housing 324, and prc~ent longitudinal or rotational movement of the anvil or cartridge assemblies relative to the housing. Pins 444 also prevent rotational movement of the collar tube or channel relative to housing 324.

Thc pro~imal end of clamp tube 327 is coDnected to the distal end of clamp tube snap 404 (see Figs. 17 and 22). As shown in Fig. 22, clamp tube snap 404 includes two distal legs 458 which e~tend into the prox;mal end of clamp tube 324. Outwardly e~tending pins 460 isolate clamp tube 324 and clamp tube snap 404 relative to one another. Clamp tube snap 404 further includes a substantially cylindrical midsection 462 and clamp snap fiDgcrs 464. It will further bc appreciated that inward deflection of collet fingers 410 by distal movement of sleeve 422 also inwardly deflects clamp snap fingers 464 from their rest position shown in Fig. ~7.

~ hannel 329 is disposed within clamp tube 327 and is longitudinally movable therein for imparting longitudinal motion to cams 331 and knifc 332.
Refcrring to Figs. 17 and 23, the pro~imal end of channcl 329 is fi~et to the distal end of channel adaptor 406, such as by tabs 466 on channel adaptor 406 2 ~ ~ -"'~ ,"~jl engaging corresponding slots on channel 329 (not shown). The shaft of channel adaptor 406 e~tends longitudinally through the center of clamp tube snap 404 and terminates with a female snap-in receptor defined by prongs 468.

The preferred frame for this embodiment is shown in Figs. 24~31.

As shown in Figs. 24, 25A and 25B, the frame and haodle assembly ;D this embodiment is configured with a double handle. In this embodiment, inner handle 470 controls the tissue clamping action of the instrument jaws, and outer handle 472 controls firing of the instrument. Frame 474, which may be molded and/or machined in wholc or in part, is substantially rectanguiar with a closed pro~imal end 478, a lower gripping surface 480 and an upper, handle receiving surface 482. An opening 484 is provided to receive handles 470, 472 mounted to hingc pin 486. Handles 470, 472 may be biased in the open position, illustratcd in Fig. 24, as by spring loading. The distal portion of opening 484 is defined by an upwardly e~tending lip 488. The lower surface of the frarne includes a protruding bulbous region 490 distal to gripping surface 480.
As explained in greater detail below, bulbous re~ion 490 defines an interior cavity 492 sufficient to permit arcuate travel of the handles. The distal end of framc 474 terminates at a substantially flat surface having a distal opening 498 (see Fig. 25B). Preferably, framc 474 is cast and/or machincd in two left and right halves fastened together by screws or rivets 496, 497, 499. Each frame half includes a distal iDwardly projecting flange 500 and a longitudinal rib 502 which define distal opening 498 (see Fig. 25B). Inwardly projecting flange 500, in conjunction with the e~cterior walls of frame 474 and interior walls S04, define a distal frame chambcr 506 to reccive and support the pro%imal end of an ou~er tubc 494.

Referring now to Figs. 24, ~6A and 26B, inDer handle 470 includes a gripping tab portion S06 at the pro~imal end of an inncr handle arm S08 and a lever arm portion 510. A hinge pin aPCrturc 512 is provided st the distal end of arm 508 to receive hinge pin 486, such that inner handle 470 rotates about -~3-h ~ ' J . ':-hinge pin 486 to obtain le~eraging mechanical advantage at lever arm ~10. Asshown in Fig. 26B, a distal end view of the inner handle, lever arm portion 510 is formed in a substantially U-shaped configuration with 8 pair of Iever arm forks SIOA, 510B. Referring again to Fig. 26A, each leveraging fork includes an elongated siot 514 for recciving frame clamp tube pins 516 projecting from either side of a frarne clamp tube 518 straddled by le~er arm forks 510A, 5]0B

~ rame clamp ~ube S18 is best described by reference to FJ8S. 27A through 27E. Fi~. 27A is a bottom view of frame clamp tube 518 showing clamp tube pins 516 projecting outwardly to either side to engage slots 514 on the inner handle lever arm portion. An clongated U-shaped slot 524 is providcd for reasons e~plained later. As shown in Figure 27B, a front side view of tube S18, a spring retaining pin 522 is formed and protrutes outwardly from the frame clamp tube. As shown in Fig. 27C, a side cross section view of the frame clamp tube$
the distal end of frame clamp tube 518 includes a circumferential recess 526 configured a~d dimensioned to receive clamp tube snap 564. Fig. 27D is a partial rear side view of the clamp tube showing the proximal end of the clamp tube. As there shown, the rear side of clamp tube 518 includes a Icaf spring slo~ 520 and a leaf spring cam 521. Fig. 27E is a partial rotated view of tube 518 showing cam 521. As shown, cam 521 is formed by bending a section of the tube wall to protrude outward from the circumference of the tube. Frame clamp tube 518 is longitudinally movable from the pro~imal position shown in Fig. 24 to a distal position to close the instrument jaws. The distal end of a clamp tube spring 519 engages spring retaining pin 522 and the pro~imal end of clamp tube spring Sl9 engages the screw mount 497. Thus, clamp tube spring 519 retains the frame elamp tube in the pro~imal position until force is e~erted to mo~e the tube to the distsl position. As shown in Fig. 24, the distal end of frame clamp tube ~18 is disposed within outer tube 494. In the pro~imal elamp tube position there illustrated, the distal end of thc frame clamp tube is substantially aligned with the distal end of the cylindrical barrel of outer tube 494.

h Referrin8 now to Figs. 24 and 29, outer tube 494 is substantially cylindrical and engages the distal opening in frame 474. The pro~imal, frame engaging portion of outer tube 494 includes an annular flange 534 wbich, together a distal outer tube body section S36, define an annular groove 537 for receiving inward flange 500 at the distal end of frame 474. Longitudinal ribs 502 on the frame (shown in phantom) engage the e~cterior outer tube surface to stabilize outer tube 494 relative to frame 474. Outer tube 494 is fi~ted relative to frame 474, as by compression fit and/or locking engagement of one or more corresponding sets of pins and holes~ etc. Thus, outer tube 494 projects from the distal end of framc 474 but is fi~ed relative to the frame.
The projecting distal end of outer tube 494 is configured and dimensioned to engage collet 402 on the endoscopic portion of the instrument (see Fig. 17).
The outer diameter of body section 536 is configured and dimensioned to be inserted iDto sleeve 422~ with collet fingers 410 simultancously urged within outer tube 494 by inwardly inclined rin~ 538. As shown in Fi8. 29, body section 536 includes collet finger recesses 540 havin~ slightly inclined distal walls 542. Body section 536 further includes transition walls S44 between the collet finger receiving portion and the cylindrical barrel section 546. Cylindrical barrel scction 546 has a uniform diameter from the pro~imal termination point of inclined walls 544 to the pro~imal eDd of outer tube 494. As stated, cylindrical barrel section 546 receives frame clamp tube 518 in concentric longitudinal sliding relation (see Fig. 24). The protruding distal portion of outer tube 494 also includes a small bump, protrusion or detent pin 501 for engaging one of detcnt slots 503 on the inner surface of sleeve S22 (see Fig.
20), such thst sleeve S22 may be rotated between distinct detent positions relative to outer tube 494.

Outer handle 472 includes a pro%imal tab portion 548, a longitudinal arm portion SS0, and a le~er arm portion S52 (see Figs. 24, 30A and 30B). The pro~imal end of longitudinal arm portion S52 terminates in tab S48, and the distal end Or arm portion S50 ineludes a hinge piD aperture S54 for receiving hinge pin 486 (see Fig. 24).

2 ~J ~

As shown ;D Figs. 30A and 30B, outer handlc arm 518 is of substantially U-shaped configuration such that inner handlc arm 508 may bc reccived within the open interior of longitudinal arm section 550. Outer handle Icver arm portion 552 is configured and dimensioned to have an open interior section 556 which surrounds the inner handle lever arm portion and clamp tube assembly.
Open intcrior section 556 permits unrestricted longitudinal movement of the frame clamp tube in response to inner handle 470 indcpendent from the action of the outer handle. To obtain open interior section 556, outer handle lever arm portion S52 includes outwardly flared regions 558A, 558B, substantially parallel body walls 56QA, 560B and a neck region S62 terminating at distal end portions 564. Referring to Fig. 30A, each distal end portion 564 includes a sprocket wheel pin receiving aperture 566.

Referring again to ~i8. 24, a sprocket wheel 56B is mounted on sprocket wheel pin 566 and engages a chain 570. Onc end of ehain S70 is fi~ed to frame 474, as by being secured to a pin mount 572. The other end of chain 57Q is fi~ed to a chain engaging tab 574. Chain engaging tab 574 is attached as a townwardly e~tending tab at the pro~imal eDd of ~ drive tube 576. Drive tube 576 is disposed within frame clamp tube 518 and slides freely relative thereto. As wi]l be apprcciated, when outer handle 472 is closed toward the upper frame surface 482 outcr handle lever portion 552 is rotated in the distal dircction. This motion causes sprocket wheel Sb8 to follow an arcuate path, within the open bottom regiOD 592 of the frame, drawing ehain 570 and, consequently, drive tube S76 in~the distal direction. lt will be noted that elongated opening 524 on the bottom of frame clamp tube 518 accommodates chain 570 to ensure free movement of the chaiD and frame clamp tube rclative to cach other. In addition, a drive tube spring 577 engages frame screw mount 499 and a pin (not shown) within drive tube 576 to retain the drive tube in the pro~imal position shown until the instrument is fired.

Briefly turning to Fig. 31, a sidc view of drive tube 576, the distal end of drive tube 576 is provided with an a~ially mounted protruding stem 578 bearing a push plug S80. Push plug 580 has a chamfered distal tip and is configured and dimensioncd to be rcccived bctwcen thc pro~imal fingers 468 on channcl adaptor 406 (see Fig. 17). As shown in thc scctional portion of Fig.
31, the rear wall of drive tubc 576 is provided with a safe~y locking slot 579.

Advanta8eously, 8 safety locking mechanism is provided in this embodiment to prevent accidental firing of the instrument. Referrin8 to Figs.
28A and 28B, a leaf spring 528 is provided having a shank portion 529 and a curved tip 530. Curved tip 530 includes curved tip shoulders 531 of equal width to shank portion 529 e~tending appro%imately half the length of curved tip 530. Curved tip S30 further includes a central drive tube locking tip 533 protruding thc full length of curved tip S30. Referring a~ain to Fig. 24, the central region S32 outlined in phantom is a furthcr partial sectional view looking beyond the far wall of drive tubc 576. This rela~ionship is better illustrated ;D Figs. 32A and 32B, which are top plan views showing the frame clamp tube 518 in pro~imal aDd distal positions, respectively, relative to leaf spring 528. Leaf spring S28 is mounted to frame 474, as by screw mounting through screw hole S35 (sce Fig. 28B), with curved tip 530 e~teDding and biascd ~oward frame clamp tube S18 and drive tube S76. ID the pro~imal positions of tubes 518, 576, drive tube locking pin 533 e~tends through slot 520 on the far side of frame clamp tube 518 (sce Figs. 27D and 32A) and engages safety locking slot 579 on drivc tubc S76 (shown in phantom in Fig. 32A). Thus, in the pro~imal position, Icaf spring S28 and lockin~ pin S33 securely lock the drive tube in thc pro~imal position and the instrument cannot be fired. Howe- er, leaf spring shoulder portions S31 do not e~ctend into slot S20, but rathcr ride outside and to either side of slot S20. As frame clamp tube 518 moves from the pro~imal to the distal posi~ion, one of shoulder portions S~l rides onto leaf spring cam S21, theseby forcing leaf spring S28 away from tubes 518, S76 and disengaging locking pin 533 from safcty locking slot 579 (see Fig. 32B). The Ieaf spring remains disenga~ed from the drive tube while thc frame n~ r1~,',jZ' clamp tube is in the distal position, and returns to locking engagemcnt with drive tube 576 whcnever îramc clamp tube 518 is rcturned to thc pro~imal position. Advantageously, thc force e~crted by Icaf sprin~ ~28 against cam 521 ~Iso tends to retain frame clamp tube 518 in thc distal position, so that the instrument will remain in the clamping position ;D prcparation for firing. In the position shown in Fig. 32B, frame clamping tube 518 is in thc distal position to clamp the instrument jaws closed, but drivc tube 576 remains iD the pro~imal position. However, bccause safety locking pin S33 is disengaged from slot S79 (shown in phantom~, the outer handlc may now bc closcd to movc drive tube 576 distally to fire the instrument.

In order to assemble the frame and endoscopic portions of the instrument constructed in accordance with this embodiment, outer tube 494 is axially aligned with and inscrted into slceve 522 until col]et fingers S10, and more specifically annular fianges 416 on the collet fin~ers, engage collet fin8er recesses 540. In addition, as outcr tube 494 is inserted into slecvc 522, (i) clamp tubc snap 564 is inserted into frame clamp tube 518 and mates with corresponding recesses 526 of the frame clamp tube; and (ii) channel adaptor 406 is a%ially inscrted through the frame clamp tube until push plug S80 is seatcd bctwcen channel adaptor fingers 468.

It will be noted that, in this embodiment, endoscopic portion 300 can be rotated relative to frame 301 by e~erting rotational force on sleeve 422. As stated, detcnt pin 501 and detent slots 503 on thc outer tube and sleeve, respcc~ively, define distinct rotational positions of the endoscope portion relative to the frame. As the cndoscopic portion rotates, collct 402 rotates relativc to outer tube 494, clamp tube snap 564 rotates vithin îrame clamp tube 518, and push plug ~80 rotates within channel sdaptor fingers 468. It will further be noted that iD the starting position of thc handles illustraled in Fig. 24, sprin~s S19, 577 bias the framc clamp tube and drive tube into thcir pro~timal positions. Thc relatcd mcchanical linkages also urge handlcs 470, 472 -2~-.

2~3~

into the opcn positions illustrated. Drive tube locking pin ~33 engages drive tube safety locking slot 579 to lock thc drive tube in the pro%imal position and, hence, handle 572 in the open position, until the instrument jaws are clamped closed.

Tissue clamping is effected by closing inner handle 470 against upper frame surface 482. As inner handle 470 pivots about hinge pin 486, pins 516 travel in slots 514 to draw frame clamp tube 518 in the distal direction, overcoming the force of thc frame clamp tubc spring 519 to advance frame clamp tube ~18 to its distal position. Because frame clamp tube 518 engages clamp tube snap 564, movement of frsmc clamp tube 518 imparts longitudinal motion to clamp tubc 327, thereby closing anvil 336 against the tissue en~aging surface of cartridge 337. Moving the frame clamp tube to the distal position also causes leaf spring cam 521 on frame clamp tube 518 to engage and urge Ieaf spring 52~ away from drive tube 576, thereby disengaging drive tube locking pin 533 from safety locking slot 579.

Thereafter, the instrumcnt may be fired by closing outer handle 472 against the inner handle and frame. During this motion, sprocket whcel 568, via chain 570, overcomes the force of drive tube sprin~ 577 and imparts distal longitudinal motion to drive tube 576 and, hcnce, to channel adaptor 40~. Of course, distal longitudinal motion of channel adaptor 406 drives channel 329, cams 331 and knife 332 to eject staples from the cartridge and form an incision between the rows of staples placed.

In this embodiment, endoscopic portion 300 may be detached from frame and handle portion 301 by e~ertinR distal force OD sleeve 422. As pre~iously stated, during such motion incliDed surfaces 414t 436 cooperate to fle% the collet fiDgers inward, thereby releasing the collet from outer tube 494.
Collet fingers 410 in turn flex clamp tube snap 464 to disengage the clamp tube snap from the framc clamp tube. Finally, as sufficient withdrawing force is developed, the distally inclined surfaces of channel sdaptor fingers 468 cause ? ( ~, the cbannel adaptor fingcrs 468 to release push plug 580, thercby permitting full disengagerneDt of the endoscopic portion from thc frame. Of coursc, the withdrawing forcc requircd to release channel adaptor fingers 468 should be sufficiently grcat that opening outer handlc 472 aftcr firing the instrumcnt does not rcsul~ in disen~agcment of the push plug from the channe] adaptor.

Advantagcously, the doublc-handle and safety locking pin arran~ement of this cmbodiment prc~ents accidental firing of the instrument with the jaws in thc open position. That is, because the outer firing haDdlc is mounted over the clamping handle and cannot be closed without previously and independently closing thc inner clarnping handle, it is impossible to fire the instrument until the jaws arc fully closed to clamp tissue.

Further alternative embodimcnts are contcmplated in which all or part of the instrument would be disposable. Where the entire instrument constitutes a single use~ disposablc instrument, the cndoscopic portion preferably would be inte~ral with thc frame and as much of the instrument as possiblc would be constructcd of plastic. In other contemplated embodiments the cartridge, knife and possibly thc anvil might be disposable, alone or as a unit. It is also contemplated, for e~ample, that a replaceable cartridge assembly could be provided which includes the knife and possibly the cam bars.

It is also preferred in all cmbodiments to include a sealin~ member within the housing in order to effect an interDal seal within the housing. Of course, such a sealing membcr, not hcrc illustratcd, must pcrmit longitudinal movement of thc clamping and firing elements.

Suitablc matcrials for use in coDstructing thc instrumcnt in accordance with thc invention include stainless stecl, titanium, aluminum and plastic.
Where disposability of all or part of the instsument is desired, plastic is the material of choice for economic rcasons. Plastic is also prcferred, where possible, in order to minimize the overall weight of the instrument. Of course, certain parts, such as the anvil, have performance requirements which dictate the material used. In the case of the anvil, the need for high streDgth and accurately shaped depressions to deform the staples ~ypically requires use of a metal, such as stainless steel. Similarly, the knife requires 8 fine cutting edge and typically is also madc from stainless steel.
The staples used with thc present iDventiOn may be non-absorbable plastic or metal or an absorbable synthetic material, such as a copolymer of polyglycolic acid. Of course, the foregoing identification of materials is e~emplary only, and Dumerous variations, substitutions and changes in material will occur to shose of ordinary skill in the art.

2~:~3a~

OPERATION OF THE INSTRUMENT

In ~lse, the endoscopic portion of the instrument is inserted into the body, preferably through an endoscopic tube. It is further preferred that the endoscopic tube apparatus be eapable of maintalning a sealed pneumoperitoneum, with the internal sealing member of the housing further maintaining this seal despite introduction of the instrument in accordance with the invention into the endoscopie tube. As a practical matter, the ja~vs of the instrument are elosed for insertion into the endoscopie tube, either by piDching the anvil and eartridge prior to insertion or by elosing the elamping mechanism prior to insertion.

After insertion into the endoscopie tube, the endoscopic portion may be rotated in order to appropriately orient the instrument at the stapling site.
Rotation of the endoscopic portion relative to the body may be attained by rotating the instrument, as a whole, by rotating the endoscopic portion relative to the frame using finger wheel 123 (see Fig. I) or slee~e S22 (see Fig. 17)~ or any eombination thereof.

~ i~3 ~ " -.

Referring additionally now to Figs. 15A and 15B, with the instrDments propcrly oriented so that the tissue to be fastened 201, 202 is disposed be~ween the open jaws of the instrument, i.e., between the tissue contacting surfaees of anvil member 136, 336 and cartridge 137, 337, the jaws are closed to clamp the tissue. In the first embodiment, the surgeon presses down on toggle lever 104, thereby sliding collar 127 distally, via collar shaft 125, collar pivot wheel 115, eollar pivot holder 112, and collar moving pivot 111.
As collar 127 moves distally in the direction of arrow A from a first position where the camming ed8e 127B at the distal end of eollar 127 is pro~cimal to hinge 136C (Fig. 15A), to a second position where the camming surface 127B is distal to the hinge 136C (Fig. lSB), the camming edge 127B contacts the upper surfaee of the anvil arms 136B, thereby forcing anvil member 136 to rotate in the direction of arrow B until the fastener forming surface 136E is brought into close cooperative alignment with the cartridge assembly, i.e., the slots 137A are aligned with staple forming depressions 136D. Fig. 15B illustrates the instrument with the jaws in a closed position. In the second embodiment described above, the sam~ result is obtained by closing inner handle 470 to impart longitudinal motion to frame clamping tube S18 and clamping tube 337, thereby close anvil 336 against cartridge 337. It is contemplated that achieving proper instrument placement may require multiple attempts to clamp the tissue prior to firing the instrument.

After closing the instrument jaws, the instrument is ready to be fired.To fire the instrument in the first embodiment, the surgeon presses push button 117, whereby the knife 132 and cam bars 131 are driven longitudinally through the cartridge via eam bar chaDnel 129, ehannel pivot 122, ehannel pin holder 121, and firing support shaft 1]7. As e~plained above, as the eam bars 131 are driven longitudinally through the eartridge, tbe staple drive members 139 push staples 138 through the body tissue against anvil 136, ~vhere the staples 138 Bre erimped. In the seeond deseribed embodiment, outer handle 472 is elosed to impart loDgitudinal motion to dri-~e tube S76, ehannel 329, eams 331 and knife 332 to fire the staples and make an jrC;~ n 2 ~ '3 fl It will be undcrstood that various modifications can be madc to thc various embodiments of the present invention herein disclosed without dcparting from the spirit and scope thereof. For c~ample, various sizes of the instrument are contemp]ated, as wcll as various types of construction materials. Also, various modifications may be madc in the configuration of the parts. For c~tample, in the first embodimcnt thc elongated slot for allowing access to the thumbwheel may bc placcd slternatively in thc Icft body portion or right body portion. Therefore the abovc description should not be construed 8S limitatiDg the invention but merely as e~cmplifications of preferred embodiments thereof. Those skilled iD the art will envisioD other modifications wlthin the scope and spirit of the prescnt invcntion as defincd hy thc claims appended hcrcto.

Claims (22)

1. A surgical apparatus for driving surgical fasteners into body tissue comprising:

a) a frame;

b) an endoscopic portion detachably connected to said frame, said endoscopic portion defining a longitudinal axis and extending distally from said frame, said endoscopic portion including:

i) an elongated housing supporting at the distal end thereof a cartridge assembly, said cartridge assembly including a plurality of surgical fasteners slidably mounted therein, and having a tissue engaging surface;

ii) an anvil member having a fastener forming surface, and a proximal end mounted to said elongated housing such that the anvil member is movable between an open position and a closed position wherein said fastener forming surface is in close cooperative alignment with said tissue engaging surface of said cartridge assembly;

iii) means for moving said anvil member between said open position and said closed position;
and iv) means for ejecting said surgical fasteners from said cartridge assembly.

2. The surgical apparatus of claim 1 additionally comprising means for rotating said endoscopic portion around said longitudinal axis.

3. The surgical apparatus of claim 1 wherein said means for moving said anvil member between said open and said closed positions further comprises a collar tube having a shaft portion disposed within and longitudinally movable relative to said housing and a clamping portion protruding from the distal end of said housing, said clamping portion surrounding a portion of said anvil member, said collar tube being movable between a first position wherein said clamping portion is adjacent said housing and a second position wherein said clamping portion is distal to said housing and urges said anvil member into said closed position.

4. The surgical apparatus of claim 1 wherein said anvil member is movably mounted to said housing by a leaf spring.

5. The surgical apparatus according to claim 1 wherein said means for ejecting said surgical fasteners further comprises at least one cam bar for actuating pusher elements within said cartridge assembly to drive said fasteners as said cam bar longitudinally traverses said cartridge assembly.

6. The surgical apparatus of claim 5 further comprising a knife mounted to said cam bar.

7. The surgical apparatus according to claim 1 wherein said cartridge assembly is removably mounted to said elongated housing.

8. The surgical apparatus according to claim 1 wherein said cartridge assembly further includes a knife.

9. A method of endoscopically driving fasteners into body tissue comprising the steps of:

a) providing an endoscopic tube inserted into a body containing body tissue to be fastened;
b) providing a surgical apparatus for driving surgical fasteners into body tissue, said apparatus including, 1) a frame;
2) an endoscopic portion defining a longitudinal axis and extending distally from said frame, said endoscopic portion comprising:
i) an elongated housing supporting a cartridge assembly at the distal end thereof, said cartridge assembly including a plurality of surgical fasteners slidably mounted therein, and having a tissue engaging surface;

ii) an anvil member having a fastener forming surface, and a proximal end mounted to said elongated housing such that said anvil member is moveable between an open position and a closed position wherein said fastener forming surface is in close cooperative alignment with said tissue engaging surface of said cartridge assembly;

iii) anvil moving means for moving said anvil member between said open position and said closed position; and iv) ejecting means for ejecting said surgical fasteners from said cartridge assembly;

c) inserting said endoscopic portion of said surgical apparatus into said endoscopic tube;
d) actuating said means for moving said anvil member from said open position to said closed position; and e) actuating said means for ejecting said surgical fasteners from said cartridge assembly.

10. The method of claim 9 further comprising the steps of:
releasing said anvil means to return said anvil to said open position; and withdrawing said endoscopic portion from said endoscopic tube.

11. A surgical apparatus for driving surgical fasteners into body tissue comprising:

a) a frame;
b) a tubular portion defining a longitudinal axis and extending distally from said frame, said tubular portion including:

i) an elongated housing having means for mounting a cartridge assembly, said cartridge assembly including a plurality of surgical fasteners mounted therein, and having a tissue engaging surface;

ii) an anvil member having a fastener forming surface, said anvil member mounted to said elongated housing;

iii) means for effecting relative movement between said cartridge assembly and said anvil member; and iv) means for ejecting said surgical fasteners from said cartridge assembly, whereby said fasteners engage said fastener forming surface.

12. The surgical apparatus of claim 11 wherein said means for providing relative movement between said cartridge assembly and said anvil member positions said cartridge assembly and said anvil member in cooperative alignment.

13. The surgical apparatus of 11 wherein said anvil member is pivotally mounted to said elongated housing.

14. The surgical apparatus of claim 13 wherein said means for providing relative movement between said cartridge assembly and said anvil member pivots said anvil member into cooperative alignment with said cartridge assembly.

15. A disposable loading unit for an endoscopic stapler apparatus comprising:
i) an elongated housing supporting at the distal end thereof a cartridge assembly, said cartridge assembly including a plurality of surgical fasteners slidably mounted therein, and having a tissue engaging surface;
ii) an anvil member having a fastener forming surface, and a proximal end mounted to said elongated housing such that said anvil member is movable between an open position and a closed position wherein said fastener forming surface is in close cooperative alignment with said tissue engaging surface of said cartridge assembly;
iii) means for moving said anvil member between said open position and said closed position; and iv) means for ejecting said surgical fasteners from said cartridge assembly, said elongated housing, anvil member and cartridge assembly being configured and dimensioned to be received by and fit into an endoscopic tube.

16. The surgical apparatus of claim 15 wherein said means for moving said anvil member between said open and said closed positions further comprises a collar tube having a shaft portion disposed within and longitudinally movable relative to said housing and a clamping portion protruding from the distal end of said housing, said clamping portion surrounding a portion of said anvil member, said collar tube being movable between a first position wherein said clamping portion is adjacent said housing and a second position wherein said clamping portion is distal to said housing and urges said anvil member into said closed position.

17. The surgical apparatus of claim 15 wherein said anvil member is movably mounted to said housing by a leaf spring.

18. The surgical apparatus according to claim 15 wherein said means for ejecting said surgical fasteners further comprises at least one cam bar for actuating pusher elements within said cartridge assembly to drive said fasteners as said cam bar longitudinally traverses said cartridge assembly.

19. The surgical apparatus of claim 18 further comprising a knife mounted to said cam bar.

20. The surgical apparatus of claim 15 wherein said cartridge assembly is removably mounted to said elongated housing.

21. The surgical apparatus according to claim 20 wherein said cartridge assembly further includes a knife.

22. The surgical apparatus of claim 19 wherein said cartridge assembly, means for ejecting said surgical fasteners, and knife are removably mounted to said elongated housing for replacement as a unit.