Surgical stapler

Abstract

A surgical device is described herein that can be used to fire different types and sizes of disposable loading units. In a preferred embodiment, the device applies parallel rows of surgical fasteners to body tissue and concomitantly forms an incision between the rows of staples during an endoscopic or laparoscopic surgical procedure. The device can be utilized with disposable loading units configured to apply linear rows of staples measuring from about 15 mm in length to about 60 mm in length and can be used to fire disposable loading units containing surgical clips and individual staples.

1. A surgical stapler comprising:
 a) a handle assembly including a stationary handle and a pivotable handle mounted for manipulation through an actuating stroke;  
 b) an elongated body extending distally from the handle assembly and defining a longitudinal axis;  
 c) an actuation member supported within the handle assembly and mounted for linear movement in response to movement of the pivotable handle through the actuation storage;  
 d) a staple cartridge supported by the elongated body and containing a plurality of staples;  
 e) an anvil mounted adjacent the cartridge, the anvil having a fastener forming surface thereon and being mounted for relative movement with respect to the cartridge between an open position spaced from the staple cartridge and a closed position in closed cooperative alignment with the staple cartridge; and  
 f) an actuator operatively connected to the actuation member, the actuator being configured to move relative to the staple cartridge and anvil to initially effectuate relative movement of the anvil and cartridge from an open position to a closed position and to subsequently effectuate sequential ejection of the staples from the cartridge in response to movement of the pivotable handle through the actuation stroke.  
 
     
     
       2. A surgical stapler as recited in  claim 1 , wherein the actuation member includes a toothed rack and the pivotable handle includes a spring biased pawl member configured to selectively engage the toothed rack to advance the actuation member in response to manipulation of the pivotable handle. 
     
     
       3. A surgical stapler as recited in  claim 2 , further comprising an engagement hook disposed within the handle assembly and biased toward the toothed rack for initially engaging a keeper notch formed adjacent a distal end of the toothed rack to limit the extent of the linear movement of the toothed rack. 
     
     
       4. A surgical stapler as recited in  claim 3 , further comprising release means for manually disengaging the engagement hook from the keeper notch. 
     
     
       5. A surgical stapler as recited in  claim 4 , wherein the release means includes at least one release knob operatively associated with the handle assembly, and a pivoting release member operatively connected to the release knob which has a release finger projecting therefrom to interact with a flange projecting from the engagement knob. 
     
     
       6. A surgical stapler as recited in  claim 4 , wherein the toothed rack has a particular rack length and the staple cartridge houses a staple line having a particular linear dimension which is less than or equal to the rack length of the toothed rack. 
     
     
       7. A surgical stapler as recited in  claim 6 , further comprising retracting means for effectuating manual retraction of the toothed rack in a proximal direction at any point in the actuating stroke to facilitate retraction of the actuator and movement of the anvil from the closed position to the open position. 
     
     
       8. A surgical stapler as recited in  claim 7 , wherein the retracting means comprises at least one retracting knob operatively associated with the handle assembly, and a release plated mounted adjacent the toothed rack and movable with respect thereto in response to initial proximal movement of the retracting knob for moving the engagement hook and the pawl out of engagement with the toothed rack. 
     
     
       9. A surgical stapler as recited in  claim 8 , wherein the release plate includes a pair of spaced apart, angled cam slots, and a pair of cam pins project laterally from the toothed rack to interact with the angled cam slots so as to facilitate relative movement of the release plate and the toothed rack. 
     
     
       10. A surgical stapler as recited in  claim 9 , further comprising a constant force spring disposed adjacent a proximal end of the handle assembly and operatively connected to the toothed rack for biasing the toothed rack in a proximal direction. 
     
     
       11. A surgical stapler as recited in  claim 2 , wherein the actuator includes an elongated actuation beam having a coupling at a proximal end thereof for receiving the distal end portion of an elongated control rod, and a support flange at a distal end portion thereof supporting a knife block configured to form an incision in stapled body tissue. 
     
     
       12. A surgical stapler as recited in  claim 11 , wherein the actuator further includes a cam roller mounted adjacent the support flange and configured to translate relative to an exterior camming surface of the anvil to effectuate movement of the anvil from the open position to the closed position. 
     
     
       13. A surgical stapler as recited in  claim 11 , wherein an actuation sled is supported within the staple cartridge and is mounted to translate ahead of the support flange to sequentially interact with a plurality of staple pushers housed within the staple cartridge adjacent the staples. 
     
     
       14. A surgical stapler as recited in  claim 13 , wherein the actuation sled is only mounted for translation in a distal direction in response to movement of the actuation beam. 
     
     
       15. A surgical stapler as recited in  claim 11 , wherein the staple cartridge and the anvil form part of a disposable loading unit, the disposable loading unit further including a carrier having a distal housing portion configured to support the staple cartridge and anvil, and a proximal mounting portion dimensioned for reception in the distal end portion of the elongated body. 
     
     
       16. A surgical stapler as recited in  claim 15 , further comprising a lockout assembly mounted within the carrier adjacent a proximal end thereof and configured to interact with the distal end portion of the control rod to limit the range of longitudinal translation of the control rod within the coupling at the proximal end of the actuation beam once the toothed actuation rack has been withdrawn to a proximal-most position. 
     
     
       17. A surgical stapler as recited in  claim 16 , wherein the lockout assembly includes a spring biased blocking plate mounted for movement in a direction transverse to the longitudinal axis of the elongated body between an initial non-blocking position and a subsequent blocking position. 
     
     
       18. A surgical stapler as recited in  claim 17 , wherein a support plate is mounted for linear translation with the carrier from a first position, wherein the blocking plate is maintained in the non-blocking position against the bias of a spring to a second position spaced distal of the blocking plate. 
     
     
       19. A surgical stapler as recited in  claim 18 , wherein the actuation beam includes means for engaging the support plate to move the support plate from the first position to the second position.