Abstract:
A surgical instrument comprising a handle portion, an elongated portion defining a longitudinal axis and extending distally from the handle portion, and first and second jaw members dimensioned to clamp tissue therebetween. The first jaw member has at least one row of fasteners arranged in a row substantially transverse to the longitudinal axis. A pin is disposed in mechanical cooperation with the first jaw member and is movable between a first position where the engagement section is spaced from the second jaw member and a second position where the engagement section engages the second jaw member. The pin has a non-circular cross-section.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a Continuation of U.S. patent application Ser. No. 14/822,947 filed Aug. 11, 2015, now U.S. Pat. No. 9,314,264 which is a Continuation of U.S. patent application Ser. No. 13/672,725 filed Nov. 9, 2012, now U.S. Pat. No. 9,113,869, which is a Continuation of U.S. patent application Ser. No. 12/753,998 filed Apr. 5, 2010, now U.S. Pat. No. 8,328,064, which claims benefit of and priority to U.S. Provisional Application No. 61/175,815 filed May 6, 2009, and the disclosures of each of the above-identified applications are hereby incorporated by reference in their entirety. 
     This application claims priority from provisional application Ser. No. 61/175,815, filed May 6, 2009, the entire contents of which are incorporated herein by reference. 
    
    
     BACKGROUND 
     Technical Field 
     The present disclosure relates generally to a surgical instrument and, more specifically, to a surgical instrument for clamping, severing, and joining tissue. 
     Background of Related Art 
     Certain surgical stapling instruments are used for applying rows of staples through compressed living tissue. These surgical stapling instruments are employed, for example, for fastening tissue or organs prior to transection or resection or during anastomoses. In some cases, these surgical stapling instruments are utilized for occluding 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 cartridge and anvil assemblies, an alignment or guide 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. 
     In use, the alignment pin assembly is advanced and the anvil and cartridge assemblies are approximated. Next, the surgeon fires the instrument to place staples in tissue. Optionally, the surgeon may use the same instrument or a separate device to cut the tissue adjacent or between the row(s) of staples. The alignment pin in some instances is advanced automatically with approximation of the cartridge; in other instances it is advanced by a separate mechanism. 
     SUMMARY 
     The present disclosure provides a surgical instrument comprising a handle portion, an elongated portion defining a longitudinal axis and extending distally from the handle portion, and an end effector disposed adjacent a distal portion of the elongated portion including a first jaw member and a second jaw member dimensioned to clamp tissue therebetween. 
     A pin is disposed in mechanical cooperation with the first jaw member and includes an engagement section and is movable between a first position wherein the engagement section is spaced from the second jaw member and a second position wherein the engagement section engages the second jaw member. The pin has a non-circular cross-section. 
     Preferably, a knife is provided to move distally to cut the clamped tissue. Preferably, the knife has an upper edge terminating alongside the pin. In one embodiment, the pin has a gap dimensioned to accommodate the knife. The instrument can include rows of fasteners with the knife positioned between the rows. 
     In one embodiment, the pin is substantially semi-circular in cross-section. In another embodiment the pin is substantially L-shaped in cross-section. 
     The instrument can include a second non-circular pin. In one embodiment, the pins are spaced from each other and one pin is adjacent a top portion of a knife and the other pin is positioned adjacent a bottom portion of the knife. The pins can be positioned on opposite sides of a knife slot from which the knife extends. 
     In some embodiments, the instrument can further include a second pin having a substantially semi-circular cross section, each of the pins having a substantially planar surface, the substantially planar surface of the second pin facing a direction opposite the direction the substantially planar surface the other pin faces. 
     The pins in some embodiments can move in a distal direction automatically when the first and second jaw members move to a position to clamp tissue. 
     In another aspect, a surgical instrument is provided comprising a handle portion, an elongated portion defining a longitudinal axis and extending distally from the handle portion, and an end effector disposed adjacent a distal portion of the elongated portion. The end effector included a first jaw member and a second jaw member, the first and second jaw members dimensioned to clamp tissue therebetween. The first jaw member has at least one row of fasteners arranged in a row substantially transverse to the longitudinal axis. A pin is disposed in mechanical cooperation with the first jaw member and includes an engagement section, the pin movable between a first position wherein the engagement section is spaced from the second jaw member and a second position wherein the engagement section engages the second jaw member. A second pin is spaced from the first pin, the first pin and second pin each having a surface alongside the knife wherein the first surface of the first pin faces in a first direction and the second surface of the second pin faces in a second opposite direction. 
     In some embodiments, the first and second surfaces of the pins are substantially planar. The first pin can have a third surface facing toward a top surface of the knife and the second pin can have a fourth surface facing towards the bottom surface of the knife. In some embodiments, the pins move in a distal direction automatically when the first and second jaw members move to a position to clamp tissue. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       Various embodiments of the presently disclosed surgical stapling instrument are disclosed herein with reference to the drawings, wherein: 
         FIG. 1  is a perspective view of a surgical stapling instrument of the present disclosure; 
         FIG. 1A  is a perspective view of an end effector of the instrument of  FIG. 1 ; 
         FIG. 1B  is a side cross-sectional view of the end effector of the instrument of  FIG. 1  with the jaw members in the open position; 
         FIG. 1C  is a side cross-sectional view of the end effector of  FIG. 1  with the jaw members in the closed position; 
         FIG. 2  is a close up perspective view of one embodiment of the cartridge assembly having a pin with a semi-circular cross-section; 
         FIG. 3  is a perspective view of the area of detail designated in  FIG. 2 ; 
         FIG. 4  a close up perspective view of another embodiment of the cartridge assembly having four rows of staples; 
         FIG. 5  is a close up perspective view of another embodiment of the cartridge assembly; 
         FIG. 6  is a close up perspective view of the area of detail designated in  FIG. 5 ; and 
         FIG. 7  is a close up perspective view of another embodiment of the cartridge assembly having two pins with a semi-circular cross-section. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Embodiments of the presently disclosed surgical stapling instrument are described in detail with reference to the drawings, wherein like reference numerals designate corresponding elements in each of the several views. In the description that follows, the term “proximal” refers to the end or portion of the surgical stapling instrument closer to the user, whereas the term “distal” refers to the end or portion of the surgical stapling instrument further from the user. 
     In the interest of brevity, the present disclosure focuses on the pin for a surgical stapling instrument designated in the drawings by reference numeral  100 . U.S. Pat. No. 7,407,076, the entire contents of which are incorporated by reference herein, describes in detail the structure and operation of an embodiment of surgical stapling instrument  100 . 
       FIG. 1  illustrates a surgical stapling instrument  100  designed for applying fasteners and cutting tissue. In brief, surgical stapling instrument  100  includes a handle portion  110 , an elongate portion  120 , and an end effector  130  extending from the distal portion of the elongate portion  120 . Handle portion  110  contains a trigger  140  for actuating end effector  130 . Elongate portion  120  extends distally from handle portion  110  and defines a longitudinal axis A-A therealong. End effector  130  is disposed adjacent to a distal portion of elongate portion  120  and includes a first jaw member or cartridge assembly  150  and a second jaw member or anvil assembly  160 . In this embodiment, cartridge assembly  150  is adapted to move longitudinally with respect to anvil assembly  160  upon actuation of trigger  140  to clamp tissue between the jaw members  150 ,  160 . It is also contemplated that the anvil assembly can be moved (approximated) toward the cartridge assembly or that the cartridge and anvil assemblies can both be moved toward each other to clamp tissue. 
     Cartridge assembly  150  includes a plurality of slots  152  ( FIGS. 1B and 1C ) each capable of holding a staple or any other suitable fastener. Each slot  152  is operatively associated with a pusher thrust bar or plunger  122 . Pusher  122  extends along elongate portion  120  and partially into cartridge assembly  150 . Cartridge assembly  150  also includes a knife advanceable to cut tissue clamped between the cartridge and anvil assemblies  150 ,  160 , respectively. In use, pusher  122  moves distally upon actuation of trigger  140  and causes the ejection of the staples disposed in slots  152  in a distal direction, substantially parallel to the longitudinal axis of the elongate portion  120 . In addition to slots  152 , cartridge assembly  150  includes a pin  154  operatively connected to pusher  122  and a bore  156  dimensioned to slidably receive pin  154 . Pin  154  is adapted to move longitudinally along bore  156  in response to a translation of pusher  122 . The pin  154  can alternatively be moved by a sliding knob  155  in the handle portion  110 . In the embodiment depicted in  FIG. 1A-1C , anvil assembly  160  has a hole  162  designed to receive at least a portion of pin  154 . Anvil assembly  160  has staple-deforming pockets  164  for deforming the fasteners ejected from cartridge assembly  150 . An elongated slot can be provided between the pockets  164  in the anvil assembly to accommodate the knife described below. 
     While anvil assembly  160  remains stationary with respect to cartridge assembly  150  during operation, cartridge assembly  150  is movable longitudinally between a proximal position and a distal position upon actuation of trigger  140 . In the proximal position, cartridge assembly  150  is spaced apart from anvil assembly  160 , as seen in  FIG. 1B  in an approximated position. The actuation of trigger  140  causes clamp slides  170 , operatively connected thereto, to move distally which in turn causes thrust bar  122  to move distally due to pins  174 . In turn, the distal translation of thrust bar  122  causes the distal movement of cartridge assembly  150  toward anvil assembly  160  to an approximated position. While cartridge assembly  150  moves from the proximal position toward the distal position, end effector  130  clamps any tissue “T” placed between cartridge assembly  150  and anvil assembly  160  as shown in  FIG. 1C . In the distal position, cartridge assembly  150  is located closer to anvil assembly  160  and presses tissue “T” against anvil assembly  160 . 
     Further actuation of trigger  140 , i.e. a second squeeze of the trigger  140 , once cartridge assembly  150  reaches its distal (approximated) position causes ejection of the fasteners from slots  152 . That is, the continued distal translation of pusher  122 , once cartridge assembly  150  is located in the distal position, causes the deployment of the fasteners positioned in slots  152 . During deployment, these fasteners exit slots  152  and advance through tissue and into contact with staple-deforming pockets  164  of anvil assembly  160  for formation thereof, e.g. bending of the staple legs into a “B” configuration. Actuation of trigger  140  also advances the knife to sever tissue clamped between the cartridge and anvil jaw assemblies  150 ,  160 . 
     Note the distal motion of clamp slides  170  causes alignment pin  154  to move distally along bore  156  due to the operative connection of the alignment pin pusher  172  to the clamp slides  170  via pins extending through elongated slots in pin pusher  172  as described in U.S. Pat. No. 7,407,076. (Pin pusher  172  includes a vertical portion having an abutment member configured to engage the proximal end of the pin  154 .) Upon sufficient distal movement of pin  154 , hole  162  of anvil assembly  160  receives a portion of pin  154 . The structural interaction between pin  154  and hole  162  (when cartridge assembly  150  is located in the distal position) assists in the alignment of slots  152  with staple-deforming pockets  164 . It should be appreciated that alignment pin  154  can alternatively be moved manually as pin pusher  172  is moved manually, e.g. by sliding knob  155 . 
     Turning now to embodiments of the alignment pins of the present disclosure illustrated in  FIGS. 2-7 , these pins can be used with the stapler of  FIG. 1  described above or with other suitable surgical staplers. They can be configured to move automatically with approximation of the cartridge, i.e. in response to actuation of the trigger, and/or moved by the user separate from approximation, e.g. by an independent slidable knob or other manual controls or knobs located at various portions of the instrument. Thus, it should be understood that it is contemplated that the pins disclosed herein can be moved in either way (automatic or manual) or in both ways. 
       FIGS. 2 and 3  illustrate a close up view of the cartridge assembly  150  of  FIG. 1 . In this embodiment, cartridge assembly  150  includes a plurality of staple slots  132  and a knife slot  134 . Each staple slot  132  houses a staple or fastener  136 . Knife slot  134  is adapted to receive knife  138 . Knife  138  is configured to move longitudinally to cut tissue between the staple rows. Preferably, knife  138  is advanced distally when the staples are advanced from cartridge assembly  150  through tissue. In this embodiment, two rows of staples are provided, extending substantially linearly and substantially transverse to longitudinal axis A-A of the instrument  100 . A different number of staples and staple rows are also contemplated. 
     Cartridge assembly  150  further includes a bore  156  configured to receive a pin  154 . Pin  154  is adapted to move longitudinally between a proximal position and a distal position and has a substantially semi-circular cross-section to allow passage of knife  138  adjacent the pin  154 . That is, the knife  138  passes by (alongside) the substantially planar inner surface region of the pin  154 . The substantially semi-circular shape of pin  154  allows the knife  138  to extend up to the region of the pin  154 . As shown, the knife  134  extends past the bottom  154   a  of the pin  154  and terminates adjacent an intermediate region  154   b  of the pin  154 . Other knife heights are also contemplated. The staple slots  156  and staple line extend beyond the top edge  138   a  of the knife  138  and beyond the bottom edge  138   b  of the knife  138 . 
       FIG. 4  illustrates an alternate embodiment of the cartridge assembly, designated generally by reference numeral  250 . Cartridge assembly is substantially identical to cartridge assembly  150  of  FIG. 2 , except that four rows of staples are provided. As shown, the four substantially linear rows of staples  236  are arranged substantially transverse to the longitudinal axis A-A of the instrument, with two staggered rows positioned on either side of knife  238 . As in the other embodiments herein, the staples  236  are fired in a direction substantially parallel to the longitudinal axis of the instrument. The knife  238  is movable from knife slot  234  to sever tissue clamped between the cartridge and anvil assemblies. Pin  254  is substantially semi-circular shaped, similar to pin  154 . The staples  236  extend beyond the upper and lower edges  238   a ,  238   b , respectively, of knife  238 . 
     In the alternate embodiment of  FIG. 5 , cartridge assembly, designated generally by reference numeral  350 , is substantially identical to cartridge assembly  150  of  FIG. 2 , except for the configuration of pin  354 . As shown, two substantially linear rows of staples  236  are arranged substantially transverse to the longitudinal axis of the instrument, with one row positioned on either side of knife  338 . A different number of rows are also contemplated. The knife  338  is movable from knife slot  334  to sever tissue clamped between the cartridge and anvil assemblies. The staples  336  extend beyond the upper and lower edges  338   a ,  338   b , respectively, of knife  338 . Pin  354  is substantially L-shaped in configuration to create a gap  357  to accommodate the knife. That is, portion  354   a  extends downwardly alongside the knife  338  and portion  354   b  extends transversely above the upper edge  338   a  of knife  338 . Consequently, the pin  354  extends in an arc of about 270 degrees (although other arcs are also contemplated). 
     It should be appreciated that although one alignment pin is shown, it is also contemplated that two alignment pins can be provided, e.g. one on the upper portion of the cartridge and the other on the lower portion of the cartridge. This is shown for example in the embodiment of  FIG. 7 , wherein upper pin  454  and lower pin  455  are provided in cartridge  450 . Each of the pins  454 ,  455  are substantially semi-circular in configuration, similar to pin  254  of  FIG. 2 , however the substantially L-shaped pins of  FIG. 5  could also be provided (either one at the top or bottom utilized with the substantially semi-circular pin on the opposing end or on both the top and bottom.) Note that the pins  454 ,  455  are preferably on opposing sides of the knife  438 . As in the other embodiments, the staple line extends beyond the upper edge  438   a  and lower edge  438   b  of knife  438 . 
     While the above description contains many specifics, these specifics should not be construed as limitations on the scope of the present disclosure, but merely as illustrations of various embodiments thereof. Therefore, the above description should not be construed as limiting, but merely as exemplifications of various embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto.