Replaceable staple cartridges for surgical instruments

#The present invention relates in general to surgical instruments that are suitable for endoscopically inserting an end effector that is actuated by a longitudinally driven firing member, and more particularly a surgical stapling and severing instrument that has an articulating shaft.

#Endoscopic surgical instruments are often preferred over traditional open surgical devices since a smaller incision tends to reduce the post-operative recovery time and complications. Consequently, significant development has gone into a range of endoscopic surgical instruments that are suitable for precise placement of a distal end effector at a desired surgical site through a cannula of a trocar. These distal end effectors engage the tissue in a number of ways to achieve a diagnostic or therapeutic effect (e.g., endocutter, grasper, cutter, staplers, clip applier, access device, drug/gene therapy delivery device, and energy device using ultrasound, RF, laser, etc.).

#Positioning the end effector is constrained by the trocar. Generally these endoscopic surgical instruments include a long shaft between the end effector and a handle portion manipulated by the clinician. This long shaft enables insertion to a desired depth and rotation about the longitudinal axis of the shaft, thereby positioning the end effector to a degree. With judicious placement of the trocar and use of graspers, for instance, through another trocar, often this amount of positioning is sufficient. Surgical stapling and severing instruments, such as described in U.S. Pat. No. 5,465,895, are an example of an endoscopic surgical instrument that successfully positions an end effector by insertion and rotation.

#The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention, and, together with the general description of the invention given above, and the detailed description of the embodiments given below, serve to explain the principles of the present invention.

#FIG. 1 is a perspective view of an endoscopic surgical stapling instrument for surgical stapling and severing in an open, unarticulated state.

#FIG. 2 is a left, front perspective view of an open staple applying assembly of the surgical stapling instrument of FIG. 1 with a right half portion of a replaceable staple cartridge included in a staple channel.

#The entire disclosure of U.S. patent application Ser. No. 11/082,495, entitled SURGICAL INSTRUMENT INCORPORATING AN ELECTRICALLY ACTUATED ARTICULATION MECHANISM, filed on Mar. 17, 2005, now U.S. Pat. No. 7,506,790, is incorporated herein by reference. The entire disclosure of U.S. Pat. No. 6,667,825, entitled STABLE CONJUGATED POLYMER ELECTROCHROMIC DEVICES INCORPORATING IONIC LIQUIDS, issued on Jan. 3, 2002, is incorporated herein by reference. The entire disclosure of U.S. patent application Ser. No. 11/061,908, entitled SURGICAL INSTRUMENT INCORPORATING A FLUID TRANSFER CONTROLLED ARTICULATION MECHANISM, filed on Feb. 18, 2005, now U.S. Pat. No. 7,559,450, is incorporated herein by reference.

#In FIGS. 1-3, a surgical stapling instrument 10 has at its distal end an end effector, depicted as a staple applying assembly 12, spaced apart from a handle 14 (FIG. 2) by an elongate shaft 16. The staple applying assembly 12 includes a staple channel 18 for receiving a replaceable staple cartridge 20. Pivotally attached to the staple channel 18 is an anvil 22 that clamps tissue to the staple cartridge 20 and serves to deform staples 23 (FIG. 3) driven up from staple holes 24 in the staple cartridge 20 against staple forming recesses 26 (FIG. 6) in an anvil undersurface 28 into a closed shape. When the staple applying assembly 12 is closed, its cross sectional area, as well as the elongate shaft 16 are suitable for insertion through a small surgical opening, such as through a cannula of a trocar (not shown).

#With particular reference to FIG. 1, correct placement and orientation of the staple applying assembly 12 is facilitated by controls on the handle 14. In particular, a rotation knob 30 causes rotation of the shaft 16 about its longitudinal axis, and hence rotation of the staple applying assembly 12. Additional positioning is enabled at an articulation joint 32 in the shaft 16 that pivots the staple applying assembly 12 in an arc from the longitudinal axis of the shaft 16, thereby allowing placement behind an organ or allowing other instruments such as an endoscope (not shown) to be oriented behind the staple applying assembly 12. This articulation is advantageously effected by an articulation control switch 34 on the handle 14 that transmits an electrical signal to the articulation joint 32 to an Electroactive Polymer (EAP) actuator 36, powered by an EAP controller and power supply 38 contained within the handle 14.