Cartridge-based lockout mechanism for right angle surgical stapler

Abstract

The surgical stapler includes a body, a shaft assembly, and an end effector configured to receive a staple cartridge. The end effector is actuable between an open state for receiving tissue and a closed state for clamping tissue. A closure system operably coupled to the end effector is operable to actuate the end effector from the open state to the closed state. A firing system operably coupled to the end effector is operable to fire the end effector to staple and cut the clamped tissue. A lockout member operably coupled to the closure system and the firing system is configured to inhibit actuation of the closure system to prevent closure of the end effector when an unused staple cartridge is missing from the end effector. The lockout member is also configured to inhibit actuation of the firing system to prevent repeated firing of the same staple cartridge.

Description

[Background technology]

[0001] Some surgical staplers are operable to clamp one or more tissue layers of a patient, form staples through the tissue layers to substantially seal the tissue layers together near the formed staples, and sever the clamped tissue layers to form a cut end of the operatively sealed tissue. An exemplary stapling instrument includes a pair of cooperating elongated jaw members, each adapted to be inserted into the patient and positioned relative to the tissue to be stapled. One of the jaw members supports a staple cartridge having at least two laterally spaced apart rows of staples therein, and the other jaw member supports an anvil having staple forming pockets configured to align with the rows of staples in the staple cartridge. Generally, the stapling instrument further includes one or more pusher bars actuable relative to the jaw members to drive staples from a staple cartridge through the tissue clamped between the jaw members and against the forming anvil, and to drive a knife member through the clamped tissue, thereby cutting the tissue simultaneously with or subsequent to stapling. In this manner, the stapling instrument is operable to form a plurality of laterally spaced rows of deformed staples in the clamped tissue, which may include linear rows and / or arcuate rows. The knife blade can cut the tissue along a linear or arcuate path extending between adjacent rows of staples formed in the clamped tissue.

[0002] Exemplary surgical staplers include U.S. Pat. No. 5,605,272, issued Feb. 25, 1997, entitled "Trigger Mechanism for Surgical Instruments"; U.S. Pat. No. 5,697,543, issued Dec. 16, 1997, entitled "Linear Stapler with Improved Firing Stroke"; U.S. Pat. No. 6,988,650, issued Jan. 24, 2006, entitled "Retaining Pin Lever Advancement Mechanism for a Curved Cutter Stapler"; U.S. Pat. No. 7,134,587, issued Nov. 14, 2006, entitled "Knife Retraction Arm for a Curved Cutter Stapler"; and U.S. Pat. No. 7,134,587, issued Dec. 12, 2006, entitled "Closure Plate Lockout for a Curved Cutter Stapler." No. 7,147,139 entitled "Cartridge Retainer for a Curved Cutter Stapler," issued on December 12, 2006; U.S. Patent No. 7,204,404 entitled "Slotted Pins Guiding Knife in a Curved Cutter Stapler," issued on April 17, 2007; U.S. Patent No. 7,207,472 entitled "Cartridge with Locking Knife for a Curved Cutter Stapler," issued on April 24, 2007; and U.S. Patent No. 10,045,780 entitled "Method of Applying Staples in Lower Anterior Bowel Resection," issued on August 14, 2018. The disclosures of each of the above-cited U.S. patents and U.S. patent publications are incorporated herein by reference.

[0003] While many different types of surgical stapling instruments and related components have been made and used, it is believed that no one prior to the present inventors has made or used the invention as set forth in the appended claims. [Brief description of the drawings]

[0004] 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 invention. [Figure 1A] FIG. 1 is a perspective view of an exemplary surgical stapler having a handle assembly, a shaft assembly, and an end effector, showing the tissue retaining pin actuation system in a retracted position and the end effector in an open state. [Figure 1B] 1B is a perspective view of the surgical stapler of FIG. 1A showing the tissue retaining pin actuation system in an extended position while the end effector is in an open state; [Figure 1C] 1B is a perspective view of the surgical stapler of FIG. 1A showing the end effector in a closed state via actuation of the closure system while the tissue retaining pin actuation system remains in an extended position; [Figure 1D] FIG. 1B is a perspective view of the surgical stapler of FIG. 1A showing the end effector in a fired state via actuation of the firing system for stapling and severing tissue captured by the end effector while the tissue retaining pin actuation system remains in an extended position; [Diagram 2] FIG. 1B is a partially exploded perspective view of the surgical stapler of FIG. 1A. [Diagram 3] 1B is an exploded perspective view of the actuable components of a shaft assembly of the surgical stapler of FIG. 1A, including a closure bar of the closure system, a staple bar of the firing system, and a knife bar of the firing system. [Figure 4A]FIG. 1B is a side view of the handle assembly of the surgical stapler of FIG. 1A, with various components omitted for clarity, showing the tissue retaining pin actuation system in an extended position to retain tissue while the closure system and firing system are in an inactivated state. [Figure 4B] FIG. 1B is a side view of the handle assembly of the surgical stapler of FIG. 1A, with various components omitted for clarity, showing a closure system that is actuated via a closure trigger to close the end effector, thereby clamping tissue. [Figure 4C] FIG. 1B is a side view of the handle assembly of the surgical stapler of FIG. 1A, with various components omitted for clarity, showing a firing system that fires the end effector via a firing trigger while the end effector is in a closed state, thereby stapling and severing tissue. [Diagram 5] 1B is a perspective view of the surgical stapler of FIG. 1A showing a staple cartridge unit of the end effector separated from a distal support structure of the end effector; [Figure 6] FIG. 1B is a perspective view of the distal left side of the staple cartridge unit of the surgical stapler of FIG. 1A . [Figure 7] FIG. 1B is a perspective view of the proximal right side of the staple cartridge unit of the surgical stapler of FIG. 1A . [Figure 8] 1B is an exploded perspective view of a staple cartridge unit of the surgical stapler of FIG. 1A; FIG. [Figure 9A] 1B is a side view of the end effector of the surgical stapler of FIG. 1A showing the lockout member of the end effector in a locked position when the staple cartridge unit is missing from the distal support structure; [Figure 9B] 1B is a side view of the end effector of the surgical stapler of FIG. 1A showing the lockout member in a bypass position when an unused staple cartridge unit is seated within the distal support structure; [Figure 10]FIG. 1B is a side view of a distal portion of the end effector of the surgical stapler of FIG. 1A after insertion of the staple cartridge unit into the distal support structure. [Figure 11] 1B is a cross-sectional view of a distal portion of the end effector of the surgical stapler of FIG. 1A illustrating interaction of a tissue-cutting washer of the staple cartridge unit with a distal support structure. [Figure 12A] 1B is a side cross-sectional view of the end effector of the surgical stapler of FIG. 1A showing the tissue retaining pin in a retracted position while the end effector is in an open condition; [Figure 12B] 1B is a side cross-sectional view of the end effector of the surgical stapler of FIG. 1A showing the tissue retaining pins retaining tissue in an extended position while the end effector is in an open state; [Figure 12C] 1B is a side cross-sectional view of the end effector of the surgical stapler of FIG. 1A illustrating actuation of the end effector to a closed state to clamp tissue while the tissue retaining pins remain in an extended state; FIG. [Figure 12D] 1B is a side cross-sectional view of the end effector of the surgical stapler of FIG. 1A, illustrating actuation to a fired state to staple and sever tissue while remaining in a closed state; [Figure 13] 1B is an enlarged perspective view of the handle assembly of the surgical stapler of FIG. 1A, with various components omitted for clarity, illustrating actuation of the firing system via pivoting of the firing trigger. [Figure 14] 1B is an exploded perspective view of the firing trigger of the surgical stapler of FIG. 1A. [Figure 15] FIG. 1B is a perspective view of a rotatable cam pin of the firing trigger of the surgical stapler of FIG. 1A. [Figure 16] 1B is a side cross-sectional view of the proximal end of the firing system of the surgical stapler of FIG. 1A showing engagement of an outer portion of the cam pin with a proximal edge of the staple bar of the firing system; [Figure 17] 1B is a side cross-sectional view of the proximal end of the firing system of the surgical stapler of FIG. 1A showing engagement of an inner portion of a cam pin with a proximal edge of a knife bar of the firing system; [Figure 18] 1B is a perspective view of a distal portion of the firing system of the surgical stapler of FIG. 1A, with various components omitted for clarity, showing an exemplary distal lockout mechanism operable to inhibit actuation of the closure system and the firing system. [Figure 19] FIG. 1B is a perspective view of a dual lockout lever of a distal lockout mechanism of the surgical stapler of FIG. 1A. [Figure 20] FIG. 1B is a perspective view of a stop member of a distal lockout mechanism of the surgical stapler of FIG. 1A; [Figure 21] FIG. 1B is an enlarged perspective view of the dual lockout lever of the distal lockout mechanism of the surgical stapler of FIG. 1A being driven from a first locked out position to a bypass position by a staple driver member of an unused staple cartridge unit loaded in the end effector; [Figure 22A] 1B is a side view of the distal portion of the firing system and distal lockout mechanism of the surgical stapler of FIG. 1A , showing the dual lockout lever in a first locked out position that inhibits distal actuation of the closure system to prevent closure of the end effector in the absence of an unused staple cartridge unit in the end effector. [Figure 22B] FIG. 1B is a side view of a distal portion of the firing system and distal lockout mechanism of the surgical stapler of FIG. 1A , showing the dual lockout lever pivoted to a bypass position that allows dual actuation of the closure system and the firing system for closing and firing the end effector when an unused staple cartridge unit is loaded. [Figure 22C] 1B is a side view of a distal portion of the firing system and distal lockout mechanism of the surgical stapler of FIG. 1A showing the firing system and dual lockout levers actuated distally during closure of the end effector; [Figure 22D] 1B is a side view of a distal portion of the firing system and distal lockout mechanism of the surgical stapler of FIG. 1A showing the firing system and dual lockout lever actuated further distally during firing of the end effector. [Figure 22E] FIG. 1B is an enlarged side view of the end effector of the surgical stapler of FIG. 1A showing the dual lockout lever pivoting to a second lockout position after the end effector has been fired, such that the dual lockout lever inhibits further firing of the end effector with the now-used staple cartridge unit. [Diagram 23] FIG. 1B is a perspective view of another exemplary dual lockout lever suitable for use with the distal lockout mechanism of the surgical stapler of FIG. 1A. [Figure 24] FIG. 13 is a perspective view of an end effector of another exemplary surgical stapler having a distal lockout mechanism operable to inhibit actuation of the closure and firing systems of the surgical stapler; [Diagram 25] FIG. 25 is a perspective view of the end effector of the surgical stapler of FIG. 24 with various components omitted for clarity, showing the dual lockout levers and stop members of the distal lockout mechanism. [Figure 26] FIG. 25 is a perspective view of a dual lockout lever of a distal lockout mechanism of the surgical stapler of FIG. [Figure 27] FIG. 25 is a perspective view of a stop member of a distal lockout mechanism of the surgical stapler of FIG. [Figure 28A] FIG. 25 is a side view of the end effector of the surgical stapler of FIG. 24 with various components omitted for clarity, showing the end effector in an open position with the end effector engaged with a stop member and in a first locked position with the dual lockout lever preventing closure of the end effector in the absence of an unused staple cartridge unit. [Figure 28B] FIG. 25 is a side view of the end effector of the surgical stapler of FIG. 24, with various components omitted for clarity, showing an unused staple cartridge unit loaded into the end effector, thereby pivoting the dual lockout lever from a first locked out position to a bypass position allowing closure and firing of the end effector. [Figure 28C]FIG. 25 is a side view of the end effector of the surgical stapler of FIG. 24 , with various components omitted for clarity, showing the end effector being actuated to a closed state by the closure system while the dual lockout lever remains in the bypass position. [Figure 28D] FIG. 25 is a side view of the end effector of the surgical stapler of FIG. 24, with various components omitted for clarity, showing the dual lockout lever pivoting to a second lockout position after the end effector has been fired, such that the dual lockout lever inhibits further firing of the end effector with the now-used staple cartridge unit.

[0005] The drawings are not intended to be limiting in any manner, and it is contemplated that various embodiments of the invention may be embodied in other various ways, including those not necessarily depicted in the drawings. The accompanying drawings, which are incorporated in and form a part of this specification, illustrate several aspects of the invention and, together with the description, serve to explain the principles of the invention. It will be understood, however, that the invention is not limited to the precise arrangements shown. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0006] The following description of specific examples of the present invention should not be used to limit the scope of the present invention. Other examples, features, aspects, embodiments, and advantages of the present invention will become apparent to those skilled in the art from the following description, which illustrates one of the best modes contemplated for carrying out the present invention. As will be understood, the present invention is capable of other different and obvious aspects, all without departing from the present invention. Thus, the drawings and description should be regarded as illustrative in nature, and not restrictive.

[0007] For clarity of this disclosure, the terms "proximal" and "distal" are defined herein relative to a surgeon or other operator gripping a surgical instrument having a distal surgical end effector. The term "proximal" refers to the location of an element disposed closer to the surgeon, and the term "distal" refers to the location of an element disposed closer to the surgical end effector of the surgical instrument and farther from the surgeon. Also, to the extent that spatial terms such as "top," "bottom," "upper," "lower," "vertical," "horizontal," "left," "right," and the like are used herein with reference to the drawings, it will be understood that such terms are used for illustrative descriptive purposes only and are not intended to be limiting or absolute. In that regard, it will be understood that surgical instruments such as those disclosed herein may be used in a variety of orientations and positions that are not limited to those shown and described herein.

[0008] As used herein, the terms "about," "approximately," and the like in connection with any numerical value or range of numerical values ​​are intended to encompass the exact value referenced, as well as a suitable dimensional tolerance that enables the referenced feature, or combination of features, to function for the intended purpose described herein.

[0009] I. Overview of Exemplary Right Angle Surgical Stapler 1A illustrates an exemplary right-angle linear surgical stapler (10) configured to staple and cut tissue in a variety of non-endoscopic ("open") surgical procedures including, for example, colorectal, thoracic, and bariatric procedures. The right-angle linear surgical stapler (10) (also referred to as a "right-angle linear cutter") generally includes a handle assembly (12), a shaft assembly (14) extending distally from the handle assembly (12), and an end effector (16) at the distal end of the shaft assembly (14). As described below, the end effector (16) is provided with a "right-angle" configuration such that the end effector (16) clamps, staples, and cuts tissue in a plane that extends transversely at a right angle to a longitudinal axis defined by the shaft assembly (14).

[0010] As described in more detail below, the surgical stapler (10) includes a number of actuation systems for manipulating the end effector (16) via the handle assembly (12) during a surgical procedure on a patient. Specifically, the surgical stapler (10) includes a tissue retaining pin actuation system (20) operable to initially retain tissue within the end effector (16), a closure system (22) operable to clamp tissue with the end effector (16), and a firing system (24) operable to thereafter staple and sever tissue with the end effector (16).

[0011] Although the teachings herein are shown and described in the context of a "straight" surgical stapler (10) configured to apply straight staple rows and straight cut lines in tissue, it will be understood that any one or more of the teachings herein may also be applied to surgical staplers configured to apply staple rows and cut lines in tissue in a non-straight (e.g., curved) configuration, such as surgical staplers of the type disclosed in any one or more of the references incorporated by reference herein.

[0012] A. Surgical Stapler Handle Assembly and Shaft Assembly As shown in Figure 1A, handle assembly (12) includes a housing (30) defining a pistol grip (32), a saddle-shaped slider (34) slidably disposed on top of handle housing (30), a pivotable closure trigger (36), and a pivotable firing trigger (38). The closure trigger (36) and the firing trigger (38) are operatively coupled to end effector (16) via shaft assembly (14) such that end effector (16) is configured to close, and thereby clamp tissue, in response to actuation of closure trigger (36), and thereafter staple and sever (i.e., "fire") tissue in response to actuation of firing trigger (38). FIG. 1A shows the slider (34) and closure trigger (36) in an unactuated configuration such that the end effector (16) is configured to receive tissue laterally into a gap (G) (or "aperture") defined between the cartridge housing (162) and an anvil (210) of a replaceable staple cartridge unit (160) mounted (or "reloaded") within the end effector (16). As shown in FIG. 1B, translating the slider (34) distally toward the end effector (16) causes the tissue retaining pins (176) of the staple cartridge unit (160) to extend distally to capture tissue between the anvil (210) and the cartridge housing (162). As shown in FIG. 1C, subsequent actuation of the closure trigger (36) toward the pistol grip (32) drives the cartridge housing (162) distally toward the anvil (210), thereby clamping the tissue therebetween. As shown in FIG. 1D, subsequent actuation of the firing trigger (38) toward the pistol grip (32) drives the staples distally into the clamped tissue and also uses a knife member (194) (see FIG. 8) to sever the tissue between the formed staple lines, as described in more detail below.

[0013] As shown in FIGURE 2, the surgical stapler (10) includes a pair of longitudinally extending side plates (40) that cooperate to define a frame structure of the stapler (10) that supports the tissue retaining pin actuation system (20), the closure system (22), and the firing system (24). Each side plate (40) includes a proximal frame portion (42) housed within the handle housing (30), an intermediate shaft portion (44) that defines a respective outer lateral side of the shaft assembly (14), and a distal jaw portion (46) having an upwardly extending distal hook (47). The distal jaw portion (46) cooperates with a distal end of a closure bar (50), described below, to define a U-shaped distal support structure (48) for the end effector (16) that removably receives a staple cartridge unit (160). As used herein, the term "U-shaped" refers to the shape presented by the end effector (16) in any of the side views shown herein.

[0014] As shown in FIGURE 3, slidably disposed between and supported by the side plates (40) are elongated actuatable components of an actuation system (20, 22, 24) that operatively connects the handle assembly (12) and the staple cartridge unit (160), including a closure bar (50), a staple bar (60), and a knife bar (70). The closure bar (50) includes a cartridge receiving distal portion (52) configured to receive and support the staple cartridge unit (160). The closure bar (50) and the staple bar (60) are each configured as a double-sided structure having first and second spaced apart lateral sides and an inner channel extending longitudinally therebetween. This configuration allows for arrangement of the shaft assembly (14) where the knife bar (70) is telescopically and slidably disposed within the inner longitudinal channel of the staple bar (60), which in turn is telescopically and slidably disposed within the inner longitudinal channel of the closure bar (50). Additionally, the staple bar (60) and the knife bar (70) are longitudinally translatable independently of the closure bar (50) through a range of longitudinal motion that allows for independent closure and firing of the end effector (16). As described in more detail below, the closure bar (50) is operable to actuate the cartridge housing (162) longitudinally relative to the anvil (210) to clamp tissue in response to actuation of the closure trigger (36). The staple bar (60) is operable to actuate the staple driver member (186) (see FIG. 8) longitudinally relative to the cartridge housing (162) to staple the clamped tissue. Knife bar (70) is operable to actuate knife member (194) (see FIG. 8) longitudinally relative to cartridge housing (162) and staple driver member (186) to sever clamped tissue.

[0015] The tissue retaining pin actuation system (20) of the surgical stapler (10) includes the slider (34) of the handle assembly (12), a tissue retaining pin (176) of the staple cartridge unit (160), an elongated pusher bar (80) extending longitudinally along the upper side of the shaft assembly (14), and a pusher bar driver (82) slidably disposed within the handle assembly (12). A distal end of the pusher bar (80) is configured to releasably couple with the tissue retaining pin (176) upon insertion of the staple cartridge unit (160) into the distal support structure (48) of the end effector (16). A proximal end of the pusher bar (80) is coupled to the pusher bar driver (82), which is coupled to the slider (34). Thus, longitudinal translation of the slide (34) between a proximal position and a distal position drives longitudinal translation of the tissue retaining pin (176) relative to the cartridge housing (162) between a retracted position and an extended position. As shown in FIG. 1A, the tissue retaining pin (176) is configured to assume a retracted position in which the retaining pin (176) is contained within the cartridge housing (162) when the slide (34) is in the proximal position. As shown in FIG. 1B, the tissue retaining pin (176) is configured to assume an extended position in which a distal end of the retaining pin (176) engages the anvil (210), thereby retaining tissue disposed within the gap (G) of the staple cartridge unit (160) when the slide (34) is advanced to the distal position.

[0016] The closure system (22) of the surgical stapler (10) includes a closure trigger (36) and a closure bar (50) of the handle assembly (12). As shown in Figures 2 and 4A-4C, the closure trigger (36) is pivotally connected to the handle housing (30) about a pair of laterally extending posts (90). An upper arm (92) of the closure trigger (36) having a vertically slotted distal portion is operatively connected to a proximal end of the closure bar (50) by a pair of closure links (96). A proximal end of each closure link (96) is pivotally connected to a laterally extending post (93) of the closure trigger upper arm (92). A distal end of each closure link (96) is pivotally connected to a proximal end of the closure bar (50) about a laterally extending post (54) of the closure bar (50).

[0017] As shown in Figures 4A-4B, pivoting the closure trigger (36) toward the pistol grip (32) advances the closure trigger upper arm (92) distally and downwardly, thereby driving the closure bar (50) distally via the closure link (96). The cartridge-receiving distal portion (52) of the closure bar (50) then drives the cartridge housing (162) distally toward the anvil (210). In this manner, the end effector (16) is actuated from an open state (Figures 1A-1B), in which tissue is positionable within the end effector (16), to a closed state (Figure 1C), in which tissue is clamped between the cartridge housing (162) and the anvil (210). A closure return spring (98) housed within pistol grip (32) of handle assembly (12) resiliently biases closure trigger (36) toward the unactuated condition, thereby resiliently biasing end effector (16) toward the open condition.

[0018] In this variation, the closure bar (50) is further configured to cooperate with the tissue retaining pin actuation system (20) to automatically actuate the retaining pin (176) distally to its extended position when the operator squeezes the closure trigger (36). In this regard, as best shown in Figures 4A-4B, the handle assembly (12) further includes a pair of cam yokes (100) rotatably disposed along the exterior of the closure link (96). Each cam yoke (100) includes an angled slot (102) that slidably receives a respective proximal post (54) of the closure bar (50). As the closure trigger (36) is actuated toward the pistol grip (32), the proximal post (54) rotatably drives the cam yoke (100) distally such that the cam lobes (104) of the yoke (100) engage corresponding side posts (84) of the pusher bar driver (82), thereby distally actuating the pusher bar (80) and thus the tissue retaining pin (176). Such automatic extension of the tissue retaining pin (176) during closure of the end effector (16) can be useful in cases where the operator has not manually actuated the retaining pin (176) distally via the slide (34) prior to actuating the closure trigger (36).

[0019] The closure system (22) of this embodiment is further configured to releasably lock the closure trigger (36) in an actuated position to provide effective clamping of tissue with the end effector (16) without the need to continually squeeze the closure trigger (36). As best shown in FIGS. 4A-4B, the release button (110) is pivotally disposed at the proximal end of the handle assembly (12). The locking pawl (112) extends distally from an upper end of the release button (110) and includes a pawl-like lug (114) that is resiliently biased, via a release button spring (116), into contact with an upper end of the closure trigger upper arm (92). Thus, when the closure trigger (36) is squeezed toward the pistol grip (32), the pawl-like lug (114) is configured to slide along an upper surface of the closure trigger upper arm (92). As shown in FIGURE 4B, when the closure trigger 36 reaches its fully actuated position, the pawl lug 114 fits into the proximal upper notch 94 of the closure trigger upper arm 92, thereby fully locking the closure trigger 36 in the actuated position. If the operator wishes to reopen the end effector 16, for example to reposition tissue within the end effector 16 or to release tissue after firing is complete, the operator can depress the release button 110 to disengage the pawl lug 114 from the closure trigger 36. The resilient bias provided by the closure return spring 98 then causes the closure trigger 36 to return to its unactuated state and the end effector 16 to return to the open state shown in FIGURES 1A and 4A.

[0020] Firing system (24) of surgical stapler (10) includes firing trigger (38) of handle assembly (12), staple bar (60), knife bar (70), and staple driver member (186) and knife member (194) of staple cartridge unit (160). Features of knife bar (70) and staple driver member (186) are described in more detail below in connection with FIG. As shown in Figures 2 and 4A, the firing trigger (38) of this example is configured as an assembly having a lower shroud (120) extending downwardly from the handle housing (30) and engageable by an operator, a pair of plates having arcuate upper arms (122) extending upwardly and distally from the lower shroud (120) and positioned with the handle housing (30), a rotatable cam pin (124) extending laterally between the free distal upper ends of the arcuate upper arms (122), and a firing lockout protrusion (126) extending distally from the lower ends of the arcuate upper arms (122) within the handle housing (30). The cam pins (124) and other features of the firing trigger (38) are described in more detail below in conjunction with Figures 13-17.

[0021] The firing trigger (38) is pivotally coupled to the handle housing (30) via a laterally extending pivot pin (128). Additionally, the firing trigger (38) is positioned distally of the closure trigger (36) such that the arcuate upper arm (122) of the firing trigger (38) is received within the slotted distal portion of the closure trigger upper arm (92) as the closure trigger (36) is actuated toward the pistol grip (32). As shown in Figures 4A-4B, when an operator fully squeezes the closure trigger (36) toward the pistol grip (32), a distally facing ledge (95) disposed within the distal slotted portion of the closure trigger upper arm (92) engages the cam pin (124) of the firing trigger (38) and drives the cam pin (124) distally an initial amount. This causes the lower end of the firing trigger (38) to partially pivot toward the pistol grip (32) simultaneously with the closure trigger (36), as shown in FIG. 4B.

[0022] As shown in FIG. 4C, once the end effector (16) has reached a fully closed state, further actuation of the firing trigger (38) toward the pistol grip (32) operates to "fire" the end effector (16). Specifically, an outer portion of the cam pin (124) engages a proximal edge (62) of the staple bar (60), thus driving the staple bar (60) distally relative to the closure bar (50). As described in more detail below in connection with FIGs. 12A-12D, a distal edge (64) of the staple bar (60) engages a proximal end of a staple driver member (186) within the staple cartridge housing (162), thereby driving the staple driver member (186) distally through the staple cartridge housing (162) and driving staples into the tissue clamped by the end effector (16). As firing trigger (38) is actuated toward its fully actuated state, an intermediate portion of cam pin (124) is disposed between arcuate upper arms (122) of firing trigger (38) and engages rounded proximal edge (72) of knife bar (70), thereby driving knife bar (70) distally relative to closure bar (50). As described in more detail below in connection with Figures 12A-12D, distal edge (74) of knife bar (70) engages a proximal end of knife member (194) within staple cartridge housing (162), thereby driving knife member (194) distally through staple driver member (186) to sever tissue clamped by end effector (16).

[0023] Firing system (24) of the present embodiment is preferably configured such that staple bar (60) and knife bar (70) both translate distally as firing trigger (38) is actuated through an initial range of motion toward pistol grip (32), and knife bar (70) continues to translate distally relative to staple bar (60) as firing trigger (38) is further actuated through a final range of motion toward pistol grip (32). Advantageously, such configuration ensures that tissue clamped by end effector (16) is fully stapled and that suitable hemostasis is achieved along the intended tissue cut line before the tissue is severed by knife member (194).

[0024] As shown in FIG. 2, firing system (24) further includes a knife return spring (130) housed within handle assembly (12). Knife return spring (130) is anchored at its distal end to the distal end of knife bar (70) and at its proximal end to the distal end of closure bar (50). Thus, knife return spring (130) is operable to resiliently bias knife bar (70) proximally relative to closure bar (50) and staple bar (60) upon release of firing trigger (38). As shown in FIG. 3 and FIGS. 12A-12D, knife bar (70) includes a distal hook (76) that is captured by knife member (194) to axially secure knife member (194) to knife bar (70). Thus, when the operator releases firing trigger (38) after completing the firing stroke, knife bar (70) and knife member (194) automatically retract proximally to safely house distal cutting edge (200) of knife member (194) within staple cartridge housing (162).

[0025] As shown in FIG. 2, the surgical stapler (10) of this embodiment further includes a proximal firing lockout mechanism in the form of a pivotable lever (140) that is operable to inhibit actuation of the firing trigger (38) until the end effector (16) is fully closed by the closure trigger (36). The firing lockout lever (140) is contained within the handle assembly (12) and pivotally mounted to the exterior of the proximal frame portion (42) of the left side plate (40). The firing lockout lever (140) is resiliently biased by a spring (146) toward a position where a lower tab (142) of the proximal lockout lever (140) blocks downward movement of the firing lockout protrusion (126) of the firing trigger (38), thereby inhibiting actuation of the firing trigger (38) when the closure trigger (36) has not been fully actuated to close the end effector (16). When closure trigger (36) reaches a fully actuated state, upper arm (144) of firing lockout lever (140) is driven downwardly by pawl-like lug (114) of release button (110), thereby rotating lower tab (142) away from firing lockout protrusion (126) and allowing actuation of firing trigger (38). The firing lockout lever (140) and other lockout features of surgical stapler (10) may be further configured and operative in accordance with at least some of the teachings in U.S. patent application Ser. No. 2005 / 0139994, entitled "Clamping Based Lockout Mechanism for Right Angle Surgical Stapler," filed on even date herewith, the disclosure of which is incorporated herein by reference.

[0026] Although not shown, shaft assembly (14) of surgical stapler (10) may include various additional components, such as an articulation joint, or may include rearrangements of various components such that shaft assembly (14) is modular with respect to handle assembly (12).

[0027] B. Surgical Stapler End Effector The end effector (16) of the surgical stapler (10) includes a distal support structure (48) defined by a distal portion of a side plate (40), a cartridge receiving distal portion (52) of a closure bar (50), distal portions of a staple bar (60) and a knife bar (70), and a replaceable staple cartridge unit (160). As best shown in Figures 5-8, the staple cartridge unit (160) of this variation includes a cartridge housing (162) and an anvil (210) spaced apart from one another to define an axial gap (G) therebetween for receiving patient tissue to be stapled and severed. The cartridge housing (162) is configured to clamp tissue against the anvil (210) and includes a distally-facing deck (164) that extends transversely to the longitudinal axis of the shaft assembly (14) along with the anvil (210), thereby providing the end effector (16) with a "right angle" configuration.

[0028] The cartridge deck (164) includes an elongated linear knife slot (166) configured to slidably receive a knife (198) therein, and a plurality of staple openings (168) arranged in linear rows along either side of the elongated linear knife slot (166) and configured to receive a plurality of unformed staples (170) therein. The deck (164) of this example further includes a plurality of standoff features (172) configured to be inserted with the staple openings (168) to optimize gripping and compression of patient tissue when the tissue is clamped between the deck (164) and the anvil (210). The deck (164) may be further configured in accordance with at least some of the teachings of U.S. Patent Application Serial No. 16 / 234,740, filed January 14, 2019, entitled "Surgical Stapler with Sloped Staple Deck for Varying Tissue Compression," the disclosure of which is incorporated herein by reference.

[0029] The elongated upper body portion (174) of the cartridge housing (162) slidably receives a tissue retaining pin (176) and a coupler (180) secured to a proximal end of the tissue retaining pin (176). The coupler (180) is configured to releasably couple the tissue retaining pin (176) with a distal end of a pusher rod (80) of the tissue retaining pin actuation system (20) when the staple cartridge unit (160) is seated within the distal support structure (48) of the end effector (16). An end cap member (182) secured to the proximal end of upper body portion (174) is configured to proximally restrain the tissue retaining pin (176) and coupler (180) within the cartridge housing (162), while allowing the tissue retaining pin (176) to translate between its proximal retracted position (see FIGS. 1A and 12A) and its distal extended position (see FIGS. 1B and 12B). The tissue retaining pin (176) includes a tapered distal tip (178) configured to penetrate tissue as the retaining pin (176) extends toward the anvil (210).

[0030] The lower body portion (184) of the cartridge housing (162) slidably receives a staple driver member (186) and a knife member (194) therein. As best shown in FIG. 8, the staple driver member (186) of this variation includes a base (188), a plurality of staple driver elements (190) projecting distally from the base (188), and an internal channel (192) extending axially through the staple driver member (186) and configured to slidably receive the knife member (194). Each staple driver element (190) is slidably received within a respective staple opening (168) of the cartridge housing (162) and is configured to drive a respective staple (170) from the opening (168) in response to actuation of the closure trigger (36). It will be appreciated that although the staple driver element (190) in this variation is securely affixed to the base (188), the base (188) and the staple driver element (190) may be provided separately in other variations.

[0031] Knife member (194) includes a base (196) and a knife (198) secured to and extending distally from base (196) and having a distal cutting edge (200). Knife (198) is formed with a flat, plate-like shape that enables knife (198) to make a linear cut on patient tissue. Knife member (194) is slidably received within internal channel (192) of staple driver member (186) such that knife (198) is configured to translate longitudinally through staple driver member (186) and elongated linear knife slot (166) of cartridge housing (162) to sever tissue clamped by end effector (16) upon full actuation of firing trigger (38).

[0032] As best shown in FIG. 8, the anvil (210) of the staple cartridge unit (160) includes a distal plate portion (212) and a linking arm (214) extending proximally from a lower end of the distal plate portion (212). The distal plate portion (212) is configured to cooperate with the cartridge deck (164) to clamp tissue to be stapled and severed. The distal plate portion (212) includes an elongated linear slot (216) and a plurality of staple forming pockets (218) arranged linearly along each side of the slot (216). The pockets (218) are configured to receive and deform the legs of staples (170) ejected from the cartridge housing (162) to form staples (170) in tissue clamped between the distal plate portion (212) and the cartridge deck (164).

[0033] The guide pin (230) extends longitudinally between the anvil plate portion (212) and the cartridge housing (162) and is configured to guide longitudinal translation of the cartridge housing (162) between a proximal open position (see FIGS. 1A and 12A) and a distal closed position (see FIGS. 1C and 12C). The proximal end of the guide pin (230) is restrained by the proximal tab (220) of the anvil linkage arm (214) shown in FIG. 8, and the distal end of the guide pin (230) is restrained within a lower opening (222) formed in the anvil plate portion (212). An upper opening (224) formed in the anvil plate portion (212) is configured to receive and restrain the tapered distal tip (178) of the tissue retaining pin (176) in the extended position such that the tissue retaining pin (176) may cooperate with the guide pin (230) to guide longitudinal translation of the cartridge housing (162) relative to the anvil (210). As seen in Figures 6-8, the interior of the guide pin (230) may include a longitudinal groove (232) configured to cooperate with a similar groove (234) (see Figures 12A-12D) to slidably guide the knife (198) between the retracted position and the extended position relative to the cartridge housing (162).

[0034] The staple cartridge unit (160) further includes a tissue-cutting washer (240) secured to the anvil (210) and configured to cooperate with the knife (198) to sever tissue clamped by the end effector (16). As best shown in FIGS. 8 and 10-11, the tissue-cutting washer (240) includes an elongated plate-like body (242) that extends distally along the anvil plate portion (212). The washer body (242) includes an elongated cutting element (244) that protrudes proximally through an elongated slot (216) in the anvil plate portion (212). The cutting element (244) functions as a cutting board by providing the knife's cutting edge (200) with a flat surface against which the cutting edge (200) cuts tissue. At least the cutting element (244) of the tissue-cutting washer (240) may comprise a polymeric material, such as high-density polyethylene (HDPE). In that regard, the knife (198) may cut axially into the cutting element (244) along its longitudinal centerline when cutting tissue. While the cutting element (244) of this variation provides a generally planar cutting surface, it will be understood that the cutting element (244) may alternatively be configured in other variations.

[0035] The tissue-cutting washer (240) further includes a rounded tip (246) at an upper end of the washer body (242) and a connecting arm (248) extending proximally from a lower end of the washer body (242). The washer tip (246) captures and thereby restrains the upper end of the anvil plate portion (212), and its rounded configuration promotes atraumatic interaction with patient tissue. A press-fit pin (250) is configured to be inserted through openings formed in the proximal connecting arms (214, 248) of the anvil (210) and tissue-cutting washer (240), thereby securely connecting the anvil (210) and cutting washer (240) together.

[0036] The tissue cutting washer (240) further includes a pair of side flanges (252) extending along the entire length of the anvil plate portion (212). As shown in Figures 10 and 11, each side flange (252) extends proximally to cover a respective side edge of the anvil plate portion (212) and extends distally to cover at least a portion of the distal hook (47) of each side plate (40) that defines the distal support structure (48). Thus, the side flanges (252) advantageously function to cover an axial gap (254) that may be formed between the anvil plate portion (212) and the distal hook (47), thereby preventing tissue from becoming trapped within the axial gap (254) in a manner that may cause undesirable trauma to the tissue. 11, the outer surface of the side flanges (252) may be rounded to further enhance the atraumatic characteristics of the periphery of the tissue-cutting washer (240). The tissue-cutting washer (240) may further be constructed and operative in accordance with any of the teachings of U.S. Patent Application No. [Attorney Reference No. END9086USNP1], entitled "Tissue Cutting Washer for Right Angle Surgical Stapler," filed on even date herewith, the disclosure of which is incorporated herein by reference.

[0037] C. Exemplary Loading of a Staple Cartridge Unit into a Distal Support Structure of an End Effector 9A and 9B illustrate the loading of a staple cartridge unit (160) in a new (or "unused") state into the distal support structure (48) of the end effector (16). As shown in FIG. 9A and as briefly described above, the distal support structure (48) is configured to have a U-shaped side profile having a distal side defined by the distal hook (47), a proximal side defined by the proximal portion of the distal jaw portion (46) and the distal end of the cartridge receiving distal portion (52) of the closure bar (50), and an upwardly opening axial gap disposed therebetween.

[0038] The staple cartridge unit (160), as shown in Figures 9A-9B, is provided with a staple retainer (260) that is removably positionable between the deck (164) and the anvil plate portion (212) to retain the staples (170) within the staple openings (168) and ensure proper axial spacing between the deck (164) and the anvil plate portion (212) when the staple cartridge unit (160) is inserted into the distal support structure (48). Upon removal of the staple retainer (260), the staple cartridge unit (160) assumes a U-shaped side profile similar to the distal support structure (48), having a distal side defined by the anvil plate portion (212) and the tissue-cutting washer (240), a proximal side defined by the cartridge deck (164), and an upwardly opening axial gap (G) disposed therebetween. Staple retainer (260) may further be configured and operable in accordance with any of the teachings of U.S. patent application Ser. No. 2005 / 0239962, entitled "Staple Retainer for Right Angle Surgical Stapler," filed on the same day herewith, the disclosure of which is incorporated herein by reference.

[0039] As shown in Figure 9A, the user first aligns the proximal rail (202) formed on the lower body portion (184) of the cartridge housing (162) with the inner channel (56) formed in the cartridge-receiving distal portion (52) of the closure bar (50) (see Figure 3). As shown in Figure 9B, the user then presses the staple cartridge unit (160) downwardly into the distal support structure (48) of the end effector (16) such that the proximal rail (202) of the cartridge housing (162) slides downwardly into the inner channel (56) of the closure bar (50) and the distal hook (47) of the side plate (40) slides into a groove formed distally in the tissue-cutting washer body (242) (see Figure 11). When the staple cartridge unit (160) is fully seated within the distal support structure (48), the detent projections (204) formed on the lower body portion (184) of the cartridge housing (162) are received within respective openings (58) formed in the cartridge receiving distal portion (52) of the closure bar (50), thereby removably securing the staple cartridge unit (160) within the distal support structure (48). Engagement of the cartridge detent projections (204) with the openings (58) can provide tactile and / or audible feedback to a user to confirm that the staple cartridge unit (160) is fully seated within the distal support structure (48).

[0040] As shown in FIG 9A, the distal lockout lever (270) is pivotally coupled to the distal end of the staple bar (60). The distal lockout lever (270) extends distally toward the distal edges (64) of the staple bar (60) and knife bar (70) and is configured to releasably engage a fixed distal pin (280) that extends laterally through the distal portions of the side plate (40), the closure bar (50), the staple bar (60), and the knife bar (70). The distal lockout lever (270) is resiliently biased toward a raised position shown in FIG 9A and pivotable toward a lowered position shown in FIG 9B in response to engagement of the proximal end of the staple driver member (186) upon insertion of an unused staple cartridge unit (160) into the distal support structure (48). In the raised position, the distal lockout lever (270) is locked into engagement with a fixed distal pin (280), thereby inhibiting distal actuation of the staple bar (60) and knife bar (70), and thus the firing of the staple cartridge unit (160). In the lowered position, the distal lockout lever (270) is disengaged from the fixed distal pin (280), thereby allowing distal actuation of the staple bar (60) and knife bar (70) for the firing of the staple cartridge unit (160). The distal lockout lever (270) is described in more detail below in connection with Figures 18-22E.

[0041] D. Exemplary Operation of a Surgical Stapler Having described various structural features of the surgical stapler (10) above, including the staple cartridge unit (160), an exemplary operation of the surgical stapler (10) during a surgical procedure will now be described. After loading an unused staple cartridge unit (160) into the distal support structure (48) in the manner described above, the end effector (16) is then suitably manipulated within the patient's body cavity to position patient tissue within the staple cartridge gap (G) between the anvil plate portion (212) and the cartridge deck (164). As shown in Figures 12A and 12B, the pusher rod (80) is then actuated distally via the slide (34) to drive the pusher rod (80) distally, thereby causing the tissue retaining pin (176) to extend from the cartridge housing (162) and its distal tip (178) to penetrate the tissue overlying the upper end of the cartridge deck (164) and seat within the upper end of the anvil plate portion (212). In this way, the patient tissue is securely held within the cartridge gap (G) prior to closure.

[0042] As shown in FIG. 12C, the closure bar (50) is then actuated distally via the closure trigger (36), thereby driving the cartridge housing (162) distally along the guide pins (230) and tissue retaining pins (176) to clamp the tissue between the cartridge deck (164) and the anvil plate portion (212). As shown in this embodiment, the staple bar (60) and knife bar (70) are actuated distally along with the closure bar (50) and cartridge housing (162) such that upon full closure of the end effector (16), the staple driver member (186) and knife member (194) are suitably positioned for firing. As mentioned above, the end effector (16) is releasably maintained in the fully closed condition by the locking pawl (112) of the release button (110) of the handle assembly (12).

[0043] As shown in FIGURE 12D, the staple bar (60) and knife bar (70) are then actuated distally via the firing trigger (38), thereby driving the staple driver member (186) and knife bar (70) distally through the cartridge housing (162). The staple driver elements (190) of the staple driver member (186) advance distally through the staple openings (168), thereby driving the staples (170) contained therein distally through the clamped tissue and into the staple forming pockets (218) of the anvil plate portion (212) such that the staples (170) are formed in the tissue. The knife member (194) drives the knife (198) through the elongated knife slot (166) of the cartridge deck (164), through the clamped tissue and distally against the cutting element (244) of the tissue-cutting washer (240), thereby severing the clamped tissue along a linear cut line between the innermost rows of formed staples (170). Upon fully severing the clamped tissue, the knife cutting edge (200) may penetrate distally into the cutting element (244) of the tissue-cutting washer (240). Optionally, in response to such penetration, the tissue-cutting washer body (242) may break along the knife cutting edge (200), thereby providing an audible indication to the surgeon (e.g., via a "snap" sound) that the firing stroke is complete and the clamped tissue is fully stapled and severed.

[0044] As discussed above, and as shown in FIGURE 12D, as the firing trigger (38) is actuated through an initial range of motion that will staple the tissue, the staple driver member (186) and the knife member (194) may translate distally together through the staple cartridge housing (162). As shown in FIGURE 12D, the knife member (194) may then continue to translate distally relative to the stationary staple driver member (186) as the firing trigger (38) is further actuated through a final range of motion that will cause the stapled tissue to be severed with the knife (198). In this manner, the tissue clamped by the end effector (16) is fully stapled before being severed.

[0045] As best shown in FIG. 7, a first lateral side of the lower body portion (184) of the cartridge housing (162) includes a detent arm (185) having a plurality of axially spaced recesses. In addition, a first lateral side of the base (188) of the staple driver member (186) includes a laterally extending detent post (189) that is configured to detent axially along the detent arm (206) as the staple driver member (186) is driven distally through the cartridge housing (162) when stapling the clamped tissue. As best shown in FIG. 8, a second lateral side of the base (188) of the staple driver member (186) includes a detent arm (191) having a plurality of axially spaced recesses. In addition, a second lateral side of the base (196) of the knife member (194) includes a laterally extending detent post (197) that is configured to detent axially along the detent arm (191) as the knife member (194) is driven distally through the staple driver member (186) when cutting the clamped tissue. Such a detent feature can provide tactile feedback to the surgeon when the staple driver member (186) is fully extended to staple the tissue, and thereafter when the knife member (194) is fully extended to cut the stapled tissue.

[0046] Once the surgical stapler (10) is fully fired, the surgeon releases the firing trigger (38), which causes the knife bar (70) and knife member (194) to automatically retract proximally relative to the closure bar (50) via the resilient bias of the knife return spring (130) described above. In this variation, proximal retraction of the knife bar (70) relative to the closure bar (50) also drives proximal retraction of the staple bar (60) relative to the closure bar (50), and the knife bar (70) is operatively coupled to the staple bar (60), for example, by engaging a lower tab (78) formed on a distal portion of the knife bar (70) with a lower slot (66) formed in an underside of the distal portion of the staple bar (60). Meanwhile, the above-mentioned staple detent features (185, 189) operate to maintain the staple driver member (186) in its fully extended position within the cartridge housing (162) such that the distal lockout lever (270) disengages the staple driver member (186), thereby allowing the distal lockout lever (270) to return to a raised, locked out position and prevent re-actuation of the firing trigger (38) when the staple cartridge unit (160) has been used. In this manner, the distal lockout lever (270) prevents the surgeon from inadvertently re-firing a used staple cartridge unit (160) into tissue in a manner that would result in the knife (198) severing tissue without applying staples.

[0047] After releasing the firing trigger (38), the surgeon then depresses the release button (110) on the handle assembly (12) to allow the closure trigger (36) and closure bar (50) to return to their unactuated state via the resilient bias of the closure return spring (98) described above. Such proximal retraction of the closure bar (50) draws the cartridge housing (162) proximally away from the anvil (210) so that the stapled and severed tissue may be released from the end effector (16). Proximal retraction of the closure bar (50) also retracts the staple bar (60) and knife bar (70) further proximally than their proximal home positions, thereby allowing the spent staple cartridge unit (160) to be removed from the distal support structure (48) and replaced with a new staple cartridge unit (160).

[0048] E. Further Features of the Launch System 13-17 show further features of the firing trigger (38) during the firing stroke to fire the end effector (16) and the engagement of the staple bar (60) and knife bar (70). As shown in FIGS. 13-14, and as briefly described above, the firing trigger (38) is configured as an assembly that includes a trigger shroud (120), a pair of trigger side plates (121) nested within the trigger shroud (120), each having an arcuate upper arm (122), a cam pin (124) extending laterally between and rotatably supported by the distal ends of the arcuate upper arms (122), a firing lockout element (126) disposed on a lateral side of the left trigger side plate (121), and a trigger pivot pin (128) extending laterally through the trigger shroud (120), the trigger side plate (121), and the firing lockout element (126) to pivotally connect the firing trigger (38) to the handle assembly body (30).

[0049] As best shown in FIG. 15, the rotatable cam pin (124) of the firing trigger (38) includes features that define a plurality of stepped diameters spaced laterally along a central axis of rotation of the cam pin (124). These features of the cam pin (124) include a circular central body (132), a circular concave shoulder (134) disposed on each lateral side of the central body (132), an annular groove (136) disposed laterally outward of each concave shoulder (134), and an end cap (138) disposed laterally outward of each annular groove (136). As described below, these mechanisms enable the cam pin (124) to simultaneously engage the proximal ends of the staple bar (60) and the knife bar (70) in response to squeezing the firing trigger (38) toward the pistol grip (32) to fire the end effector (16).

[0050] As shown in FIG. 16 , the circular central body (132) of the cam pin (124) is configured to engage the rounded proximal edge (72) of the knife bar (70) in response to squeezing the firing trigger (38). At the same time, each annular groove (136) of the cam pin (124) is configured to engage a respective proximal edge (62) of the staple bar (60) in response to squeezing the firing trigger (38). Thus, by squeezing the firing trigger (38) toward the pistol grip (32) to perform a firing stroke, the cam pin (124) drives the staple bar (60) and the knife bar (70) distally, thereby firing the end effector (16) in the manner described above. Cam pin (124) is rotatably mounted to trigger side plate (121) such that cam pin (124) is configured to pivot along proximal edges (62) of staple bar (60) and knife bar (70) when firing trigger (38) is squeezed. Advantageously, such pivoting minimizes frictional forces between cam pin (124) and proximal edges (62), and thus minimizes the input force (also referred to as the "firing force") that an operator must apply to firing trigger (38) to fully actuate bars (60, 70) distally and fire end effector (16).

[0051] The force applied to the staple bar (60) and knife bar (70) by the cam pin (124) during the firing stroke can result in the proximal portions of the bars (60, 70) experiencing a downward bending moment about their proximal-most support point within the shaft assembly (14). As best seen in FIG. 13, the support pin (150) is positioned below the proximal ends of the staple bar (60) and knife bar (70). The support pin (150) is configured to support the bars (60, 70) on their undersides to counteract such bending moment and prevent downward deflection of the bars (60, 70) during firing. In this embodiment, the support pin (150) extends laterally between the proximal frame portions (42) of the stapler side plate (40) and is fixed longitudinally to the stapler side plate (40), although in some variations the support pin (150) may be rotatable relative to the side plate (40).

[0052] F. Distal Lockout Mechanism of Surgical Stapler 18, the surgical stapler includes a distal lockout mechanism including a dual lockout member in the form of a lockout lever (270) and a stop member in the form of a fixed pin (280). As briefly described above and in more detail below, the distal lockout lever (270) and the fixed pin (280) are configured to cooperate to inhibit closure of the end effector (16) when an unused staple cartridge (160) is missing from the end effector (16) and to inhibit the end effector (16) from firing more than one staple cartridge unit (160).

[0053] As shown in Figures 18-20, the distal lockout lever (270) of this embodiment is configured as a two-sided structure having first and second lateral sides (272) that are spaced apart and parallel to one another and a lower bridge (273) that interconnects the proximal portions of the sides (272) along their lower edges. The proximal end of the lockout lever (270) includes a pair of openings (274) configured to receive a pivot pin (279) therein, and the distal end of the lockout lever (270) includes a pair of distally extending tabs (275). Along its intermediate portion, the lockout lever (270) further includes a proximal pair of lockout teeth (276) extending upwardly from the lever side (272) and a distal pair of lockout teeth (278) extending upwardly from the lever side (272) and spaced distally from the proximal lockout teeth (276). As described below, the lockout teeth (276, 278) are configured to engage with a proximally facing flat surface (282) of the fixation pin (280) to establish a locked out position that prevents closure and firing of the end effector (16) in the absence of an unused staple cartridge unit (160).

[0054] As shown in Figures 18 and 3, lever pivot pin (279) extends laterally through a proximal opening (274) in distal lockout lever (270), a corresponding pair of openings (67) (see Figure 3) formed in a distal portion of staple bar (60), and a corresponding slot (77) (see Figure 3) formed in a distal portion of knife bar (70). Thus, distal lockout lever (270) remains rotatably longitudinally fixed relative to staple bar (60), while slot (77) allows knife bar (70) to translate longitudinally relative to staple bar (60) and distal lockout lever (270) to actuate knife member (194) of staple cartridge unit (160) independently of staple driver member (186) in the manner described above. 18 and also shown in FIG. 3, the locking pin (280) extends laterally through an elongated slot (79) formed in a distal portion of the knife bar (70) and a corresponding pair of elongated slots (69) formed in the distal portion of the staple bar (60). As mentioned above, the opposing lateral ends of the locking pin (280) are secured within the distal jaw portion (46) of the stapler side plate (40). Thus, the elongated slots (69, 79) permit the staple bar (60) and knife bar (70) along with the distal lockout lever (270) to translate longitudinally relative to the locking pin (280) to effect closure and firing of the end effector (16) loaded with an unused staple cartridge unit (160).

[0055] 21-22E, the distal lockout lever (270) is configured to pivot relative to the staple bar (60) and knife bar (70) between a generally horizontal, raised position in which the proximal lockout tooth (276) or the distal lockout tooth (278) is configured to engage the fixed pin (280), and a lowered position in which the lockout teeth (276, 278) are configured to bypass the fixed pin (280). The distal lockout lever (270) may be biased toward the raised position by any suitable biasing element, such as a resilient member (not shown).

[0056] 22A illustrates the distal lockout lever (270) in a first, raised, locked out position that the distal lockout lever (270) is configured to assume and maintain when the end effector (16) is in an open state (i.e., when the closure system (22) and the firing system (24) are in an unactuated state) and when an unused staple cartridge unit (160) is missing from the end effector (16), such as when the unit (160) is missing entirely from the end effector (16), or when the end effector (16) is loaded with a used staple cartridge unit (160). In this first, raised, locked out position, the distal lockout tooth (278) is positioned to engage the flat surface (282) of the fixation pin (280), thereby inhibiting distal actuation of the firing system (24). Because the firing system (24) is operably coupled to the closure system (22) in the manner described above, this locking of the firing system (24) in the unactuated state also inhibits actuation of the closure system (22), thereby locking the end effector (16) in the open state.

[0057] As shown in FIGS. 21 and 22B, an unused staple cartridge unit (160) is configured to be loaded into the end effector (16) to pivot the distal lockout lever (270) to its lowered, bypass position. In particular, the staple driver member (186) of the unused staple cartridge unit (160) is positioned proximally within the cartridge housing (162) such that the proximal base (188) of the staple driver member (186) drives the distally extending tab (275) of the distal lockout lever (270) downwardly when the unused staple cartridge unit (160) is seated within the distal support structure (48) of the end effector (16). This engagement causes the distal lockout lever (270) to pivot downwardly from its first, elevated, locked out position (FIG. 22A) to the lowered, bypass position (FIG. 22B).

[0058] As shown in FIG. 22C, with the distal lockout lever (270) in the lower bypass position, the staple bar (60) and knife bar (70) of the firing system (24) can be actuated distally with the closure bar (50) in response to the operator squeezing the closure trigger (36). In this manner, the end effector (16) is closed to clamp tissue between the anvil (210) and the cartridge deck (164) of the unused staple cartridge unit (160), as shown in FIG. 1B-1C above. As shown in FIG. 22D, with the distal lockout lever (270) remaining in the lowered, bypass position, in response to squeezing the firing trigger (38), the staple bar (60) and knife bar (70) are driven further distally relative to the closure bar (50) through a firing stroke, thus firing the end effector (16) with the unused staple cartridge unit (160) to staple and sever the clamped tissue.

[0059] FIG. 22E illustrates the end effector (16) after completion of the firing stroke on the staple cartridge unit (160) such that the staple cartridge unit (160) is now spent. As discussed above in connection with FIG. 7, the staple detent features (185, 189) maintain the staple driver member (186) in a distal position within the cartridge housing (162) after the staple cartridge unit (160) has been fired. Thus, when the staple bar (60) and knife bar (70) are retracted proximally in response to the operator releasing the firing trigger (38), the distally extending tab (275) of the distal lockout lever (270) disengages the proximal base (188) of the staple driver member (186). As a result, the bias applied by the biasing member automatically pivots the distal lockout lever (270) upward to assume a second, elevated, locked out position, as shown in FIG. 22E. In the second, elevated, locked out position, the proximal lockout tooth (276) is positioned to engage the proximal flat surface (282) of the fixation pin (280), thereby preventing further actuation of the firing system (24) while the end effector (16) remains clamped with the now-used staple cartridge unit (160). In this manner, the distal lockout lever (270) inhibits the firing system (24) from being actuated more than once with the same staple cartridge unit (160) while the end effector (16) remains clamped. Advantageously, this protects against inadvertent re-actuation of the knife (198) so that the established staple line can be severed and compromised after the staples (170) have been formed in the clamped tissue. This functionality of the distal lockout lever (270) therefore reminds the operator that the used staple cartridge unit (160) must be replaced with another new, unused staple cartridge unit (160) in order to fire another shot into tissue.

[0060] As described above, after firing the end effector (16) and releasing the firing trigger (38), the operator may depress the release button (see FIGS. 1A-1D and 4A-4C) to return the closure system (22) to a deactivated state and reopen the end effector (16) to release the staples and sever the tissue. As the staple bar (60) and knife bar (70) retract proximally, the distal lockout lever (270) ratches proximally along the underside of the locking pin (280), thus returning the distal lockout lever (270) to the first, raised, locked out position shown in FIG. 22A. As a result, the operator is prevented from reclosing the end effector (16) while it is still loaded with a spent staple cartridge unit (160). Thus, advantageously, the distal lockout lever (270) is operable as a dual lockout member, in that it is configured to inhibit actuation of both the closure system (22) and the firing system (24) in the absence of an unused staple cartridge unit (160). Additionally, the distal lockout lever (270) is configured to cooperate with the proximal firing lockout lever (140) described above to ensure safe use of the surgical stapler (10).

[0061] G. Exemplary alternative distal lockout lever having a downwardly sloping distal tab 23 illustrates an exemplary alternative distal lockout lever (290) suitable for use with the surgical stapler (10) in place of the distal lockout lever (270) described above. The distal lockout lever (290) is similar to the distal lockout lever (270) in that the distal lockout lever (290) is configured as a double-sided structure having first and second lateral sides (292) that are spaced apart and parallel to one another. Additionally, the distal lockout lever (290) includes a pair of openings (294) configured to receive a pivot pin (not shown), and the distal end of the lockout lever (290) includes a pair of distally extending tabs (295). Unlike the distally extending tabs (275) of the distal lockout lever (270), which are angled upward, the distally extending tabs (295) are angled downward. Thus, the distal lockout lever (290) may be suitable for use with other types of staple cartridge units in which the proximal end of the staple driver member is shaped differently than the proximal base (188) of the staple driver member (186) described above.

[0062] Similar to distal lockout lever (270), distal lockout lever (290) further includes a proximal pair of lockout teeth (296) extending upwardly from lever side (292) and a distal pair of lockout teeth (298) extending upwardly from lever side (292). The lockout teeth (296, 298) of distal lockout lever (290) are configured to cooperate with fixed distal pin (280) in a manner similar to the lockout teeth (276, 278) of distal lockout lever (270) described above. Similar to lockout lever (270), lockout lever (290) is pivotable between a raised, locked out position and a lowered, bypass position. Lockout lever (290) is shown with a resilient member in the form of a leaf spring (299) that operates to resiliently bias lockout lever (290) toward the raised, locked out position.

[0063] II. Exemplary Alternative Distal Lockout Mechanisms In some cases, it may be desirable to alternatively configure the distal lockout mechanism of the surgical stapler end effector (16) such that the lockout member (270) is attached to the closure bar (50) rather than the staple bar (60). Figures 24-28D show an exemplary rectangular linear surgical stapler (310) having an alternative distal lockout mechanism having such a configuration. The surgical stapler (310) is similar to the surgical stapler (10) unless otherwise described below. As will be described in more detail, the distal lockout mechanism includes a movable lockout member (270) and a movable lockout member (380) operable in a manner similar to the stop member (280) of the surgical stapler (10) described above, and a fixed stop member (390). Specifically, the lockout member (380) and the stop member (390) are configured to cooperate to inhibit closure of the end effector (316) when an unused staple cartridge unit (460) is missing from the end effector (316) and to inhibit the end effector (316) from firing the same staple cartridge unit (460) more than once. The surgical stapler (310) is similar to the surgical stapler (10) described above, except as otherwise described below.

[0064] As shown in Figures 24 and 25, the surgical stapler (310) includes a shaft assembly (314) extending distally from a handle assembly (not shown) and an end effector (316) at the distal end of the shaft assembly (314). The surgical stapler (310) further includes a pair of longitudinally extending side plates (340), each having a distal jaw portion (346), and an inner jaw member (347) positioned laterally between the distal jaw portions (346). The closure system of the surgical stapler (310) includes an elongated closure bar (350) slidably disposed between the stapler side plates (340). The firing system of the surgical stapler (310) includes an elongated, actuatable staple bar (360) slidably nested within the closure bar (350), and an elongated, actuatable knife bar (370) slidably nested within the staple bar (360). The cartridge-receiving distal portion (352) of the closure bar (350) cooperates with the distal jaw portion (346) and the inner jaw member (347) of the stapler side plate (340) to define a U-shaped distal support structure (348) of the end effector (316). As shown in FIG. 24, the distal support structure (348) is configured to receive a staple cartridge unit (460), which may be similar to the staple cartridge unit (160) described above.

[0065] As shown in Figures 25-27, the distal lockout mechanism of the surgical stapler (310) includes a movable lockout member in the form of a lockout lever (380) pivotally mounted to the cartridge receiving distal portion (352) of the closure bar (350) and a fixed stop member in the form of a proximally facing lug (390) affixed to the proximal end of the inner jaw member (347). As shown in Figure 26, the distal lockout lever (380) includes a first lockout feature in the form of a proximal hook (382) at the proximal end of the lockout lever (380) and a second lockout feature in the form of a distal hook (384) at the distal end of the lockout lever (380). A tab (386) projects distally from the distal hook (384) and is configured to be engaged by a proximal end of the staple driver member (486) of the staple cartridge unit (460) to pivot the lockout lever (380) between a locked position (see, e.g., FIGS. 28A and 28D) and a bypass position (see, e.g., FIGS. 28B and 28C). The lockout lever (380) further includes a pair of pivot posts (388) extending laterally outward from opposing lateral sides of the lockout lever (380) at a midpoint of the lockout lever (380) between the proximal hook (382) and the distal hook (384). The pivot posts (388) are rotatably received within corresponding openings formed in opposing lateral sides of the cartridge receiving distal portion (352) of the closure bar (350), thus pivotally mounting the lockout lever (380) to the closure bar (350) about a lateral pivot axis.

[0066] As shown in Figures 28A-28D, the lockout lever (380) is configured to pivot about a pivot post (388) between an angled position in which the lockout lever (380) is configured to inhibit actuation of the closure and / or firing systems of the surgical stapler (310) and a generally horizontal, bypass position in which the lockout lever (380) is configured to allow actuation of the closure and firing systems of the stapler (310) to allow closure and firing of an end effector (316) loaded with an unused staple cartridge unit (460). The lockout lever (380) in this embodiment is biased toward the angled position by any suitable type of biasing member, such as a resilient member similar to the leaf spring (299) described above.

[0067] 25 and 28A show the distal lockout lever (380) in a first angled lockout position that the distal lockout lever (380) is configured to assume and maintain when the end effector (316) is in an open state (i.e., when the closure system and firing system are in an inactivated state) and when an unused staple cartridge unit (460) is missing from the end effector (316), such as when the staple cartridge unit (460) is missing entirely from the end effector (316) or when the end effector (316) is loaded with a used staple cartridge unit (460). In this first angled lockout position, the distal hook (384) captures the distal ends of the staple bar (360) and knife bar, while the proximal hook (382) captures the proximal ends of the lugs (390). As seen in FIG. 27 , the proximal end of the lug (390) includes a groove (392) configured to receive the proximal hook (382) of the distal lockout lever (380) in the first, angled, locked position. With an unused staple cartridge unit (460) missing within the end effector (316), this simultaneous engagement of the lug (390) of the distal lockout lever (380) with the staple bar (360) inhibits distal actuation of both the closure and firing systems of the surgical stapler (310), thus preventing closure of the end effector (316). Specifically, the proximal hook (382) grounds the closure bar (350) longitudinally to the stapler side plate (340) and the inner jaw member (347), and the distal hook (384) grounds the closure bar (350) longitudinally to the staple bar (360) and the knife bar (370).

[0068] As shown in FIG. 28B, upon loading of an unused staple cartridge unit (460) into the end effector (316), the distal lockout lever (380) is pivoted from the first locked out position to the horizontal bypass position. Specifically, the proximal end of the staple driver member (486) of the unused staple cartridge unit (460) engages and drives the distal tab (386) of the lockout lever (380) downwardly. This causes the lockout lever (380) to pivot to a horizontal position such that the proximal hook (382) disengages the lug (390) and the distal hook (384) disengages the staple bar (360).

[0069] Now, as shown in FIGURE 28C, with the distal lockout lever (380) in the horizontal bypass position, the closure bar (350), staple bar (360) and knife bar (370) are free to actuate distally relative to the stapler side plate (340) to close the end effector (316) and thereby clamp the tissue. As shown, the distal lockout lever (380) translates with the closure bar (350), causing the proximal hook (382) to translate distally past the proximal face of the lug (390). Additionally, once the end effector (316) is fully closed, the staple bar (360) and knife bar (370) actuate further distally relative to the closure bar (350) through a firing stroke to fire the end effector (316) with an unused staple cartridge unit (460), thereby stapling and severing the clamped tissue.

[0070] 28D illustrates the end effector (316) after completion of the firing stroke on the staple cartridge unit (460), such that the staple cartridge unit (460) is now spent. Similar to the staple driver member (186) of the staple cartridge unit (160), the staple driver member (486) of the cartridge unit (460) is configured to remain in a distal position within the cartridge housing (462) upon completion of the firing stroke. Thus, when the staple bar (360) and knife bar (370) are retracted proximally in response to the operator releasing the firing trigger (not shown) of the surgical stapler (310), the distal tab (386) of the distal lockout lever (380) disengages from the proximal end of the staple driver member (486). As a result, the bias applied by the biasing member causes the distal lockout lever (380) to automatically pivot relative to the closure bar (350) to assume a second angled lockout position, as shown in FIGURE 22D. In the second angled lockout position, the distal hook (384) of the lockout lever captures the distal ends of the staple bar (360) and knife bar (370), thus inhibiting distal actuation of the bars (360, 370) relative to the closure bar (350) and preventing re-fire, while the end effector (316) remains clamped with the now spent staple cartridge unit (460). Similar to the benefits provided in end effector (16), this functionality in end effector (316) protects the knife (not shown) of staple cartridge unit (460) from inadvertent re-activation in a manner that can cut and compromise the established staple line after staples have been formed in the clamped tissue.

[0071] When the closure bar (350), staple bar (360), and knife bar (370) are retracted proximally and the spent staple cartridge unit (460) is removed from the end effector (316), the distal lockout lever (380) is configured to automatically reassume the first angled lockout position shown in Figures 25 and 28A. In this embodiment, the distal end of the lug (390) includes a first angled surface (394) and the facing side of the proximal hook (382) of the distal lockout lever (380) includes a second angled surface (396). The ramp features are configured to cam against one another to pivot the lockout lever (380) to a bypass position as the bars (350, 360, 370) retract proximally, thereby causing the distal lockout lever (380) to retract proximally with the closure bar (350) and again assume the first angled lockout position until another new, unused staple cartridge unit (460) is loaded into the end effector (316).

[0072] III. Exemplary Combinations The following examples relate to various non-exhaustive methods in which the teachings herein may be combined or applied. It will be understood that the following examples are not intended to limit the scope of any claims that may be presented at any time in this application or in a later filing of this application. No disclaimer is intended. The following examples are provided for illustrative purposes only. It is contemplated that the various teachings herein may be configured and applied in many other ways. It is also contemplated that certain features referred to in the following examples may be omitted in some variations. Thus, none of the aspects or features referred to below should be considered as critical unless expressly indicated to be so at a later date by the inventor or the inventor's successor in interest. If a claim including additional features other than those referred to below is presented in this application or in a later filing related to this application, those additional features should not be presumed to have been added for any reason related to patentability. EXAMPLES

[0073] A surgical stapler comprising: (a) a body; (b) a shaft assembly extending distally from the body; (c) an end effector at a distal end of the shaft assembly, the end effector actuable between an open state for receiving tissue and a closed state for clamping tissue, the end effector configured to receive a staple cartridge having staples; (d) a closure system operatively coupled to the end effector, the closure system operable to actuate the end effector from the open state to the closed state; and (e) a firing mechanism operatively coupled to the end effector. A surgical stapler system comprising: (a) a firing system operable to fire the end effector, thereby stapling and severing the clamped tissue; and (b) a closure system and a lockout member operably coupled to the firing system, the lockout member configured to inhibit actuation of the closure system to prevent closure of the end effector when an unused staple cartridge is missing from the end effector, and the lockout member is further configured to inhibit actuation of the firing system to prevent repeated firing of the end effector with the same staple cartridge. EXAMPLES

[0074] The surgical stapler of Example 1, wherein the end effector is configured to clamp and staple tissue in a plane extending transverse to the longitudinal axis of the shaft assembly, and the surgical stapler is configured for use in open surgical procedures. EXAMPLES

[0075] A surgical stapler as described in Example 1 or 2, wherein the end effector includes a knife and the lockout member is configured to prevent distal actuation of the knife after an initial firing of the end effector with the staple cartridge. EXAMPLES

[0076] A surgical stapler as described in any one of Examples 1 to 3, wherein the lockout member is movable between a first position in which the lockout member is configured to inhibit actuation of the closure system and the firing system when an unused staple cartridge is missing from the end effector, and a second position in which the lockout member is configured to enable actuation of the closure system and the firing system. EXAMPLES

[0077] 5. The surgical stapler of example 4, wherein the lockout member is resiliently biased toward the first position. EXAMPLES

[0078] A surgical stapler as described in Example 4 or 5, wherein the lockout member is configured to transition from a first position to a second position in response to an unused staple cartridge being received by the end effector. EXAMPLES

[0079] A surgical stapler as described in Example 6, wherein the staple cartridge includes a staple driver member configured to eject staples from the staple cartridge in response to actuation of the firing system, and the lockout member includes a protrusion configured to be engaged by the staple driver member when an unused staple cartridge is initially received by the end effector, the engagement being configured to drive the lockout member from a first position to a second position. EXAMPLES

[0080] A surgical stapler as described in Example 6 or 7, wherein when an unused staple cartridge is seated within the end effector, the lockout member is configured to translate distally with the closure system while maintaining the second position. EXAMPLES

[0081] A surgical stapler described in any one of Examples 6 to 8, wherein the lockout member is configured to automatically return from the second position to the first position after the end effector is fired with an unused staple cartridge. EXAMPLES

[0082] The surgical stapler of any one of Examples 4 to 9, wherein the lockout member comprises a lever configured to pivot between a first position and a second position. EXAMPLES

[0083] A surgical stapler as described in Example 10, wherein the shaft assembly extends along a longitudinal axis and the lever is configured to pivot about a lateral axis extending transversely to the longitudinal axis. EXAMPLES

[0084] A surgical stapler as described in any one of Examples 1 to 11, wherein the lockout member is configured to translate distally relative to the body together with the closure system when the closure system actuates the end effector from an open state to a closed state. EXAMPLES

[0085] A surgical stapler as described in any one of Examples 12, further comprising a stop member fixed longitudinally relative to the body, wherein the lockout member is configured to engage with the stop member to inhibit distal actuation of the closure system when an unused staple cartridge is missing from the end effector in an open state. EXAMPLES

[0086] A surgical stapler as described in any one of Examples 1 to 13, wherein the lockout member includes (i) a first lockout feature operable to inhibit actuation of the closure system to prevent closure of the end effector when an unused staple cartridge is missing from the end effector, and (ii) a second lockout feature operable to inhibit actuation of the firing system to prevent repeated firing of the end effector with the same staple cartridge. EXAMPLES

[0087] 15. The surgical stapler of example embodiment 14, wherein the first and second lockout features are longitudinally spaced apart along the longitudinal axis of the shaft assembly. EXAMPLES

[0088] A surgical stapler comprising: (a) a body; (b) a shaft assembly extending distally from the body; (c) an end effector at a distal end of the shaft assembly, the end effector actuable between an open state for receiving tissue and a closed state for clamping tissue, the end effector configured to receive a staple cartridge having staples; (d) a closure system operatively coupled to the end effector, the closure system operable to actuate the end effector from the open state to the closed state; and (e) a firing system operatively coupled to the end effector, the firing system being operable to activate the end effector from the open state to the closed state. 1. A surgical stapler comprising: a firing system, the stem of which is distally actuable through a firing stroke to eject staples from the staple cartridge into clamped tissue; and (f) a lockout member operably coupled to the closure system and the firing system, the lockout member including: (i) a first lockout feature operable to inhibit actuation of the closure system when an unused staple cartridge is missing from the end effector; and (ii) a second lockout feature operable to inhibit repeated actuation of the firing system with the same staple cartridge through multiple firing strokes. EXAMPLES

[0089] 17. The surgical stapler of example embodiment 16, wherein the first and second lockout features are spaced apart along the length of the lockout member. EXAMPLES

[0090] 18. A surgical stapler as described in Example 16 or 17, wherein the first lockout feature comprises a first protrusion and the second lockout feature comprises a second protrusion. EXAMPLES

[0091] 1. A surgical stapler comprising: (a) a body; (b) a shaft assembly extending distally from the body; (c) an end effector at a distal end of the shaft assembly, the end effector actuable between an open state for receiving tissue and a closed state for clamping tissue, the end effector configured to receive a staple cartridge having staples; (d) a closure system operably coupled to the end effector, the closure system operable to actuate the end effector from the open state to the closed state; (e) a firing system operably coupled to the end effector, the firing system distally actuable through a firing stroke to eject staples from the staple cartridge into clamped tissue; and (f) a lockout lever operably coupled to the closure system and the firing system, the lockout lever pivotable between a first position, where the lockout lever is configured to inhibit actuation of the closure system and the firing system, and a second position, where the lockout lever is configured to enable actuation of the closure system and the firing system. EXAMPLES

[0092] 20. The surgical stapler of claim 19, wherein the lockout lever is disposed within the end effector.

[0093] IV.Other It should be understood that any one or more of the teachings, expressions, embodiments, examples, etc. described herein can be combined with any one or more of the other teachings, expressions, embodiments, examples, etc. described herein. Thus, the above teachings, expressions, embodiments, examples, etc. should not be considered in isolation with respect to each other. In light of the teachings herein, various suitable ways in which the teachings herein can be combined will be readily apparent to those skilled in the art. Such modifications and variations are intended to be included within the scope of the claims.

[0094] Furthermore, any one or more of the teachings, expressions, embodiments, examples, etc. described in this specification may be combined with any one or more of the teachings, expressions, embodiments, examples of U.S. patent application Ser. No. 2003 / 0133634, filed on the same day herewith, entitled "Tissue Cutting Washer for Right Angle Surgical Stapler" [Attorney Reference No. END9086USNP1]; U.S. patent application Ser. No. 2003 / 0133634, filed on the same day herewith, entitled "Clamping Based Lockout Mechanism for Right Angle Surgical Stapler" [Attorney Reference No. END9087USNP1]; and U.S. patent application Ser. No. 2003 / 0133634, filed on the same day herewith, entitled "Staple Retainer for Right Angle Surgical Stapler" [Attorney Reference No. END9090USNP1], the disclosures of which are incorporated herein by reference.

[0095] Any patent, publication, or other disclosure referred to herein as being incorporated by reference should be understood to be incorporated herein, in whole or in part, only to the extent that the incorporated content does not contradict the current definitions, opinions, or other disclosures described in this disclosure. As such, and to the extent necessary, the disclosures explicitly described herein shall take precedence over any conflicting statements incorporated herein by reference. Any content, or portions thereof, that is referred to herein as being incorporated by reference but that contradicts the current definitions, opinions, or other disclosures described herein shall be incorporated only to the extent that there is no contradiction between the incorporated content and the current disclosures.

[0096] Variations of the above devices may have application in robotic-assisted treatments and procedures as well as in traditional treatments and procedures performed by medical professionals. By way of example only, the various teachings herein may be readily incorporated into robotic surgical systems such as the DAVINCI™ system by Intuitive Surgical, Inc. (Sunnyvale, California). Similarly, one of ordinary skill in the art will recognize that the various teachings herein can be readily combined with the various teachings of any of the following: U.S. Pat. No. 5,792,135, issued on Aug. 11, 1998, entitled "Articulated Surgical Instrument For Performing Minimally Invasive Surgery With Enhanced Dexterity and Sensitivity," the disclosure of which is incorporated herein by reference; U.S. Pat. No. 8,783,541, issued on July 22, 2014, entitled "Robotically-Controlled Surgical End Effector System," the disclosure of which is incorporated herein by reference; U.S. Pat. No. 8,479,969, issued on July 9, 2013, entitled "Drive Interface for Operably Coupling a Manipulatable Surgical Tool to a Robot," the disclosure of which is incorporated herein by reference; U.S. Pat. No. 8,479,969, issued on August 12, 2014, entitled "Robotically-Controlled Cable-Based Surgical End Effector System," the disclosure of which is incorporated herein by reference; No. 8,800,838, entitled “Robotically-Controlled Surgical End Effectors” (the disclosure of which is incorporated herein by reference), and / or U.S. Pat. No. 8,573,465, issued on November 5, 2013, entitled “Robotically-Controlled Surgical End Effector System with Rotary Actuated Closure Systems” (the disclosure of which is incorporated herein by reference).

[0097] The device variations described above can be designed to be disposed of after a single use, or they can be designed to be used multiple times. The variations can, in either or both cases, be reconditioned for reuse after at least one use. Reconditioning can include any combination of the steps of disassembly of the device, followed by cleaning or replacement of particular parts, and subsequent reassembly. In particular, some device variations can be disassembled, and any number of the particular parts or pieces of the device can be selectively replaced or removed in any combination. After cleaning and / or replacement of particular parts, some device variations can be reassembled for subsequent use either at a reconditioning facility, or by a user immediately prior to a procedure. Those skilled in the art will appreciate that reconditioning of a device can utilize a variety of techniques for disassembly, cleaning / replacement, and reassembly. The use of such techniques, and the resulting reconditioned device, are all within the scope of the present application.

[0098] By way of example only, the variations described herein may be sterilized before and / or after treatment. In one sterilization technique, the device is placed in a closed and sealed container, such as a plastic or TYVEK bag. The container and device may then be placed in a radiation field that can penetrate the container, such as gamma radiation, x-rays, or high-energy electrons. The radiation may kill bacteria on the device and in the container. The sterilized device may then be stored in the sterile container for later use. The device may also be sterilized using any other technique known in the art, including but not limited to beta or gamma radiation, ethylene oxide, or steam.

[0099] Although various embodiments of the present invention have been shown and described above, further adaptations of the methods and systems described herein can be realized by those skilled in the art through appropriate modifications without departing from the scope of the present invention. Although some of such possible modifications have been described, other modifications will be apparent to those skilled in the art. For example, the above examples, embodiments, shapes, materials, dimensions, ratios, steps, etc. are illustrative and not essential. Therefore, the scope of the present invention should be considered in terms of the following claims and should not be limited to the details of structure and operation shown and described in the specification and drawings.

[0100] [Embodiment] (1) A surgical stapler comprising: (a) a main body; (b) a shaft assembly extending distally from the body; (c) an end effector at a distal end of the shaft assembly, the end effector being actuable between an open state for receiving tissue and a closed state for clamping the tissue, the end effector being configured to receive a staple cartridge having staples; and (d) a closure system operatively coupled to the end effector, the closure system operable to actuate the end effector from the open state to the closed state; and (e) a firing system operatively coupled to the end effector, the firing system operable to fire the end effector, thereby stapling and severing the clamped tissue; (f) a lockout member operatively coupled to the closure system and the launch system; the lockout member is configured to inhibit actuation of the closure system to prevent closure of the end effector when an unused staple cartridge is missing from the end effector; The surgical stapler, wherein the lockout member is further configured to inhibit actuation of the firing system to prevent repeated firing of the end effector with the same staple cartridge. (2) The surgical stapler of embodiment 1, wherein the end effector is configured to clamp and staple tissue in a plane extending transverse to the longitudinal axis of the shaft assembly, and the surgical stapler is configured for use in open surgical procedures. (3) The surgical stapler of claim 1, wherein the end effector includes a knife, and the lockout member is configured to prevent distal actuation of the knife after an initial firing of the end effector with the staple cartridge. (4) A surgical stapler as described in embodiment 1, wherein the lockout member is movable between a first position in which the lockout member is configured to inhibit actuation of the closure system and the firing system when an unused staple cartridge is missing from the end effector, and a second position in which the lockout member is configured to enable actuation of the closure system and the firing system. (5) The surgical stapler of claim 4, wherein the lockout member is resiliently biased toward the first position.

[0101] (6) The surgical stapler of claim 4, wherein the lockout member is configured to transition from the first position to the second position in response to an unused staple cartridge being received by the end effector. (7) The surgical stapler of claim 6, wherein the staple cartridge includes a staple driver member configured to eject the staples from the staple cartridge in response to actuation of the firing system, and the lockout member includes a protrusion configured to be engaged by the staple driver member when the unused staple cartridge is initially received by the end effector, the engagement being configured to drive the lockout member from the first position to the second position. (8) The surgical stapler of claim 6, wherein the lockout member is configured to translate distally with the closure system while maintaining the second position when the unused staple cartridge is seated within the end effector. (9) The surgical stapler of claim 6, wherein the lockout member is configured to automatically return from the second position to the first position after the end effector is fired with the unused staple cartridge. (10) The surgical stapler of claim 4, wherein the lockout member comprises a lever configured to pivot between the first position and the second position.

[0102] (11) The surgical stapler of claim 10, wherein the shaft assembly extends along a longitudinal axis and the lever is configured to pivot about a lateral axis extending transversely to the longitudinal axis. (12) A surgical stapler as described in embodiment 1, wherein the lockout member is configured to translate distally relative to the body together with the closure system when the closure system actuates the end effector from the open state to the closed state. (13) The surgical stapler of claim 12, further comprising a stop member longitudinally fixed to the body, the lockout member configured to engage with the stop member to inhibit distal actuation of the closure system when an unused staple cartridge is missing from the end effector in the open state. (14) The lockout member is (i) a first lockout feature operable to inhibit actuation of the closure system to prevent closure of the end effector when an unused staple cartridge is missing from the end effector; (ii) a second lockout feature operable to inhibit actuation of the firing system to prevent repeated firing of the end effector with the same staple cartridge. (15) The surgical stapler of embodiment 14, wherein the first lockout feature and the second lockout feature are longitudinally spaced apart along a longitudinal axis of the shaft assembly.

[0103] (16) A surgical stapler comprising: (a) a main body; (b) a shaft assembly extending distally from the body; (c) an end effector at a distal end of the shaft assembly, the end effector being actuable between an open state for receiving tissue and a closed state for clamping the tissue, the end effector being configured to receive a staple cartridge having staples; and (d) a closure system operatively coupled to the end effector, the closure system operable to actuate the end effector from the open state to the closed state; and (e) a firing system operatively coupled to the end effector, the firing system distally actuable through a firing stroke to eject staples from the staple cartridge into the clamped tissue; (f) a lockout member operatively coupled to the closure system and the launch system, (i) a first lockout feature operable to inhibit actuation of the closure system when an unused staple cartridge is missing from the end effector; (ii) a second lockout feature operable to inhibit repeated actuation of the firing system through multiple firing strokes with the same staple cartridge. (17) The surgical stapler of embodiment 16, wherein the first lockout feature and the second lockout feature are spaced apart along a length of the lockout member. (18) The surgical stapler of embodiment 16, wherein the first lockout feature comprises a first protrusion and the second lockout feature comprises a second protrusion. (19) A surgical stapler comprising: (a) a main body; (b) a shaft assembly extending distally from the body; (c) an end effector at a distal end of the shaft assembly, the end effector being actuable between an open state for receiving tissue and a closed state for clamping the tissue, the end effector being configured to receive a staple cartridge having staples; and (d) a closure system operatively coupled to the end effector, the closure system operable to actuate the end effector from the open state to the closed state; and (e) a firing system operatively coupled to the end effector, the firing system distally actuable through a firing stroke to eject staples from the staple cartridge into the clamped tissue; (f) a lockout lever operably coupled to the closure system and the firing system, the lockout lever pivotable between a first position in which the lockout lever is configured to inhibit actuation of the closure system and the firing system and a second position in which the lockout lever is configured to allow actuation of the closure system and the firing system. (20) The surgical stapler of claim 19, wherein the lockout lever is disposed within the end effector.

Claims

1. 1. A surgical stapler comprising: (a) a main body; (b) a shaft assembly extending distally from the body; (c) an end effector at a distal end of the shaft assembly, the end effector having an anvil and configured to receive a staple cartridge having staples, the end effector being actuable between an open state in which the staple cartridge is in a proximal direction to receive tissue of a patient between the anvil and the staple cartridge, and a closed state in which the staple cartridge is in the distal direction to clamp the tissue between the anvil and the staple cartridge; (d) a closure system operatively coupled to the end effector, the closure system having a closure bar with a cartridge receiving distal portion, the closure system operable to actuate the end effector from the open state to the closed state; (e) a firing system operatively coupled to the end effector, the firing system operable to fire the staples contained in the staple cartridge received by the end effector, thereby stapling the clamped tissue; and (f) a movable lockout member in the form of a lockout lever operatively coupled to the closure system and the firing system and pivotally mounted to the cartridge receiving distal portion of the closure bar; (i) the movable lockout member is configured to include a first lockout feature operable to inhibit actuation of the closure system to prevent closure of the end effector when an unused staple cartridge is not loaded into the end effector; (ii) the movable lockout member is configured to comprise a second lockout feature operable to inhibit actuation of the firing system while the end effector is in the closed condition, except upon a first actuation of the firing system after the unused staple cartridge is loaded into the end effector, to prevent repeated firing of the end effector in the closed condition with the same staple cartridge; and the first and second lockout features are configured to be longitudinally spaced apart along a longitudinal axis of the shaft assembly; the first lockout feature comprises a first protrusion and the second lockout feature comprises a second protrusion.

2. 10. The surgical stapler of claim 1, wherein the end effector is configured to clamp and staple tissue in a plane extending transverse to the longitudinal axis, the surgical stapler being configured for use in open surgical procedures.

3. the staple cartridge further includes a knife, and the firing system is operable to fire the knife, thereby severing the clamped tissue; The surgical stapler of claim 1 , wherein the movable lockout member is configured to prevent distal actuation of the knife after an initial firing of the end effector with the staple cartridge.

4. 2. The surgical stapler of claim 1, wherein the movable lockout member is configured to: in a first position, when the unused staple cartridge is not loaded into the end effector, the movable lockout member releasably engage a fixed distal pin to inhibit actuation of the closure system to bring the end effector from the open state to the closed state and actuation of the firing system to staple and cut the clamped tissue; and in a second position, when the unused staple cartridge is not loaded into the end effector, the movable lockout member is configured to disengage from the fixed distal pin to allow actuation of the closure system to bring the end effector from the open state to the closed state and actuation of the firing system to staple and cut the clamped tissue; and the movable lockout member is movable between the first position and the second position.

5. The surgical stapler of claim 4 , wherein the movable lockout member is resiliently biased toward the first position.

6. 5. The surgical stapler of claim 4, wherein the movable lockout member is configured to transition from the first position to the second position in response to the unused staple cartridge being received by the end effector.

7. 7. The surgical stapler of claim 6, wherein the staple cartridge includes a staple driver member configured to eject the staples from the staple cartridge in response to actuation of the firing system, and the movable lockout member includes a tab extending distally of the movable lockout member configured to be engaged by the staple driver member when the unused staple cartridge is initially received by the end effector, the engagement being configured to drive the movable lockout member from the first position to the second position.

8. 7. The surgical stapler of claim 6, wherein the movable lockout member is configured to translate distally with the closure system while maintaining the second position when the unused staple cartridge is seated within the end effector.

9. 7. The surgical stapler of claim 6, wherein the movable lockout member is configured to automatically return from the second position to the first position after the end effector has been fired with the unused staple cartridge.

10. The surgical stapler of claim 4 , wherein the movable lockout member is configured to pivot between the first position and the second position.

11. 11. The surgical stapler of claim 10, wherein the shaft assembly extends along the longitudinal axis and the movable lockout member is configured to pivot about a lateral axis extending transversely to the longitudinal axis.

12. 2. The surgical stapler of claim 1, wherein the movable lockout member is configured to translate distally relative to the body with the closure system when the closure system actuates the end effector from the open condition to the closed condition.

13. 13. The surgical stapler of claim 12, further comprising a fixed stop member in the form of a proximally facing lug affixed to a proximal end of an inner jaw member that is longitudinally fixed relative to the body, the movable lockout member being configured to engage the fixed stop member to inhibit distal actuation of the closure system when the unused staple cartridge is not loaded into the end effector in the open condition.

14. 1. A surgical stapler comprising: (a) a main body; (b) a shaft assembly extending distally from the body; (c) an end effector at a distal end of the shaft assembly, the end effector having an anvil, the end effector configured to receive a staple cartridge having staples, the staple cartridge being actuable between a proximal open state for receiving tissue between the anvil and the staple cartridge and a distal closed state for clamping the tissue between the anvil and the staple cartridge; (d) a closure system operatively coupled to the end effector, the closure system having a closure bar with a cartridge receiving distal portion, the closure system operable to actuate the end effector from the open state to the closed state; (e) a firing system operatively coupled to the end effector, the firing system distally actuable through a firing stroke to eject the staples from the staple cartridge into the clamped tissue; (f) a movable lockout member in the form of a lockout lever operatively coupled to the closure system and the firing system and pivotally mounted to the cartridge receiving distal portion of the closure bar; (i) a first lockout feature operable to inhibit actuation of the closure system when an unused staple cartridge is not loaded into the end effector; (ii) a second lockout feature operable to inhibit repeated actuation of the firing system with the same staple cartridge in the closed condition through multiple firing strokes while the end effector is in the closed condition, except upon a first actuation of the firing system after the unused staple cartridge is loaded into the end effector; the first lockout feature and the second lockout feature are spaced apart along a length of the movable lockout member; the first lockout feature comprises a first protrusion and the second lockout feature comprises a second protrusion.

15. 1. A surgical stapler comprising: (a) a main body; (b) a shaft assembly extending distally from the body; (c) an end effector at a distal end of the shaft assembly, the end effector having an anvil and configured to receive a staple cartridge having staples, the end effector being actuable between a proximal open state of the staple cartridge for receiving tissue between the anvil and the staple cartridge and a distal closed state of the staple cartridge for clamping the tissue between the anvil and the staple cartridge; (d) a closure system operatively coupled to the end effector, the closure system having a closure bar with a cartridge receiving distal portion, the closure system operable to actuate the end effector from the open state to the closed state; (e) a firing system operatively coupled to the end effector, the firing system distally actuable through a firing stroke to eject the staples from the staple cartridge into the clamped tissue; (f) a lockout lever operatively coupled to the closure system and the firing system and pivotally mounted to the cartridge receiving distal portion of the closure bar, the lockout lever pivotable between a first position, where the lockout lever is configured to inhibit actuation of the closure system and the firing system, and a second position, where the lockout lever is configured to allow actuation of the closure system and the firing system. (i) the lockout lever is configured to include a first lockout feature operable to inhibit actuation of the closure system to prevent closure of the end effector when an unused staple cartridge is not loaded into the end effector; (ii) the lockout lever is configured to include a second lockout feature operable to inhibit actuation of the firing system while the end effector is in the closed condition, except upon a first actuation of the firing system after the unused staple cartridge is loaded into the end effector, to prevent repeated firing of the end effector in the closed condition with the same staple cartridge; and the first and second lockout features are configured to be longitudinally spaced apart along a longitudinal axis of the shaft assembly; the first lockout feature comprises a first protrusion and the second lockout feature comprises a second protrusion.

16. The surgical stapler of claim 15, wherein the lockout lever is disposed within the end effector.

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