Surgical stapling device with tissue gap control

Abstract

A surgical stapling device includes a drive assembly and a tool assembly having an anvil and a cartridge assembly. The cartridge assembly includes a channel member that defines a cavity, and a staple cartridge that is movably supported within the cavity of the channel member between a lowered position and a raised position. The tool assembly is movable from an open position to a clamped position to define a tissue gap between the staple cartridge and the anvil, and the drive assembly is adapted to move the staple cartridge from the lowered position to the raised position to accommodate tissue of different thicknesses.

Description

SURGICAL STAPLING DEVICE WITH TISSUE GAP CONTROLCROSS-REFERENCE TO RELATED APPLICATION(S)

[0001] This application claims priority to U.S. Provisional Patent Application No. 63 / 655,266, filed June 3, 2024, which is incorporated herein by reference in its entirety.FIELD

[0002] This disclosure is directed to surgical stapling devices and, more particularly, to surgical stapling devices including a tool assembly with tissue gap control.BACKGROUND

[0003] Surgical stapling devices for ejecting staples to join tissue or tissue segments in a fast and efficient manner during a variety of surgical procedures are well known. Typically, a surgical stapling device includes a tool assembly having a first jaw that supports a cartridge assembly and a second jaw that supports an anvil. The cartridge assembly includes a staple cartridge that supports staples, and the first and second jaws are mounted together to allow movement of the tool assembly between an open position and a clamped position. In the clamped position, the staple cartridge of the cartridge assembly and the anvil are supported in juxtaposed alignment and include tissue contact surfaces that define a predetermined tissue gap. The predetermined tissue gap and the staples are dimensioned to receive and suture tissue having a thickness within a predetermined range to affect hemostasis of the tissue. If the tissue positioned between the jaws is outside the predetermined range, i.e., either too thick or too thin, the stapling device may not provide ideal hemostasis.

[0004] Accordingly, a continuing need exists in the suturing arts for a surgical stapling device that can provide effective hemostasis for a greater range of tissue thicknesses.SUMMARY

[0005] This disclosure relates to a surgical stapling device including a drive assembly and a tool assembly having an anvil and a cartridge assembly. The cartridge assembly includes a channel member that defines a cavity, and a staple cartridge that is movably supported within the cavity of the channel member between a lowered position and a raised position. The toolassembly is movable from an open position to a clamped position to define a tissue gap between the staple cartridge and the anvil, and the drive assembly is adapted to move the staple cartridge from the lowered position to the raised position to accommodate tissue of different thicknesses.

[0006] Aspects of the disclosure are directed to a tool assembly including an anvil, a cartridge assembly, and a drive assembly. The anvil has a tissue engaging surface. The cartridge assembly is coupled to the anvil to facilitate movement of the tool assembly between an open position and a clamped position and includes a channel member and a staple cartridge. The channel member has side walls and a bottom wall that together define a cavity. The staple cartridge is supported within the cavity of the channel member and has a tissue engaging surface that is spaced from the tissue engaging surface of the anvil when the tool assembly is in the clamped position to define a tissue gap. The staple cartridge has a cartridge body that defines a knife slot and staple receiving pockets that are positioned on each side of the knife slot. The cartridge body includes inner walls that define the knife slot, and at least one of the inner walls has a longitudinally extending rail. The staple cartridge is movable within the cavity of the channel member between a lowered position and a raised position to change the size of the tissue gap. The drive assembly includes a working member with an I-beam configuration and includes a first beam, a second beam, and a strut that connects the first beam to the second beam. The strut is received within the knife slot and defines at least one cam channel. The drive assembly is movable from a drive retracted position to a drive advanced position to move the working member through the cartridge body. The at least one cam channel is positioned to receive the at least one longitudinally extending rail of the cartridge body to move the staple cartridge from the lowered position to the raised position within the cavity of the channel member.

[0007] Other aspects of the disclosure are directed to a stapling device having a handle assembly, an adapter assembly, and a tool assembly. The adapter assembly has a proximal portion and a distal portion, and the proximal portion is coupled to the handle assembly. The tool assembly is supported on the distal portion of the adapter assembly and includes an anvil, a cartridge assembly, and a drive assembly. The anvil has a tissue engaging surface. The cartridge assembly is coupled to the anvil to facilitate movement of the tool assembly between an open position and a clamped position and includes a channel member and a staple cartridge. The channel member has side walls and a bottom wall that together define a cavity. The staple cartridge is supported within the cavity of the channel member and has a tissue engaging surfacethat is spaced from the tissue engaging surface of the anvil when the tool assembly is in the clamped position to define a tissue gap. The staple cartridge has a cartridge body that defines a knife slot and staple receiving pockets that are positioned on each side of the knife slot. The cartridge body includes inner walls that define the knife slot, and at least one of the inner walls has a longitudinally extending rail. The staple cartridge is movable within the cavity of the channel member between a lowered position and a raised position to change the size of the tissue gap. The drive assembly includes a working member with an I-beam configuration and includes a first beam, a second beam, and a strut that connects the first beam to the second beam. The strut is received within the knife slot and defines at least one cam channel. The drive assembly is movable from a drive retracted position to a drive advanced position to move the working member through the cartridge body. The at least one cam channel is positioned to receive the at least one longitudinally extending rail of the cartridge body to move the staple cartridge from the lowered position to the raised position within the cavity of the channel member.

[0008] In aspects of the disclosure, the at least one longitudinally extending rail includes two longitudinally extending rails, and one of the two longitudinally extending rails is positioned on the cartridge body on each side of the knife slot.

[0009] In some aspects of the disclosure, the at least one cam channel includes two cam channels, and each of the two cam channels is positioned to receive one of the two longitudinally extending rails.

[0010] In certain aspects of the disclosure, the at least one cam channel is defined by a lower wall having a distal portion that is angled downwardly in the distal direction.

[0011] In aspects of the disclosure, the at least one longitudinally extending rail is configured to be deformed by the strut of the working member when a predetermined force is applied to the staple cartridge in a direction towards the bottom wall of the channel member.

[0012] In some aspects of the disclosure, the at least one longitudinally extending rail is configured to be sheared from the cartridge body by the strut of the working member when a predetermined force is applied to the staple cartridge in a direction towards the bottom wall of the channel member.

[0013] In certain aspects of the disclosure, the staple cartridge includes staples, pushers, and an actuation sled, and the staples and pushers are received in the staple receiving pockets.

[0014] In aspects of the disclosure, the actuation sled is movable through the cartridge body from a sled retracted position towards a sled advanced position to eject the staples from the cartridge body.

[0015] Other aspects of the disclosure are directed to a tool assembly including an anvil, a cartridge assembly, and a drive assembly. The anvil has a tissue engaging surface, and the cartridge assembly is coupled to the anvil to facilitate movement of the tool assembly between an open position and a clamped position. The cartridge assembly includes a channel member and a staple cartridge. The channel member defines a channel knife slot and has side walls and a bottom wall that together define a cavity. The bottom wall of the channel member supports at least one clamp adjustment member that has at least one guide surface. The staple cartridge is supported within the cavity of the channel member and has a tissue engaging surface that is spaced from the tissue engaging surface of the anvil when the tool assembly is in the clamped position to define a tissue gap. The staple cartridge is movable within the cavity of the channel member between a lowered position and a raised position and has a cartridge body that defines a cartridge knife slot and staple receiving pockets positioned on each side of the cartridge knife slot. The drive assembly includes a working member assembly having a body and at least one pin. The body of the working member assembly has an I-beam configuration and includes a first beam, a second beam, and a strut that connects the first beam to the second beam. The strut is received within the cartridge knife slot and the channel knife slot and defines at least one elongate slot. The at least one pin extends through the at least one elongate slot, and the at least one elongate slot includes a first end and a second end. The drive assembly is movable from a drive retracted position to a drive advanced position to move the working member through the cartridge body, and the at least one pin is positioned to engage the at least one guide surface to move the staple cartridge from the lowered position to the raised position within the cavity of the channel member.

[0016] In aspects of the disclosure, the first beam is positioned to engage the anvil and the second beam is positioned to engage the channel member of the cartridge assembly.

[0017] In aspects of the disclosure, the strut defines at least one elongate slot, and the at least one pin extends through the at least one elongate slot.

[0018] In some aspects of the disclosure, the working member assembly includes at least one biasing member that is coupled to the at least one pin, and the biasing member is positioned to urge the at least one pin towards the second end of the at least one elongate slot.

[0019] In certain aspects of the disclosure, the at least one elongate slot includes two elongate slots, the at least one pin includes two pins, and the at least one biasing member includes two biasing members.

[0020] In aspects of the disclosure, the at least one clamp adjustment member includes a first clamp adjustment member supported on the bottom wall of the channel member on a first side of the channel knife slot and a second clamp adjustment member positioned on a second side of the channel knife slot.

[0021] In some aspects of the disclosure, each of the two pins is engaged with the first clamp adjustment member and the second clamp adjustment member.

[0022] In certain aspects of the disclosure, the at least one guide surface includes an upper guide surface and a lower guide surface, and the at least one pin is movable into engagement with the lower guide surface to move the staple cartridge from the lowered position to the raised position.

[0023] In aspects of the disclosure, the at least one clamp adjustment member includes a distal end portion having an angled upper cam surface and an angled lower cam surface.

[0024] In some aspects of the disclosure, the angled upper cam surface is configured to direct the at least one pin into engagement with the upper guide surface and the angled lower cam surface is configured to direct the at least one pin into engagement with the lower guide surface.

[0025] In certain aspects of the disclosure, the staple cartridge includes staples, pushers and an actuation sled, and the staples and the pushers are received within the staple receiving slots of the cartridge body.

[0026] In aspects of the disclosure, the actuation sled is movable from a sled retracted position to a sled advanced position into sequential engagement with the pushers to move the pushers from a pusher lowered position to a pusher raised position to eject the staples from the staple cartridge into the anvil to form the staples.

[0027] In some aspects of the disclosure, the at least one pin is movable into engagement with the lower guide surfaces of the first clamp adjustment member and the second adjustment member when the drive assembly is moved from the drive advanced position towards the driveretracted position to move the staple cartridge from the lowered position to the raised position to further form the staples.

[0028] In certain aspects of the disclosure, the pushers include detents to retain the pushers in the pusher raised position.

[0029] In aspects of the disclosure, the cartridge body of the staple cartridge defines pockets that receive the detents.

[0030] Other aspects of the disclosure will be appreciated from the following description.BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Various aspects of the disclosed stapling device are described herein below with reference to the drawings, wherein:

[0032] FIG. 1 is a side perspective view of a surgical stapling device including aspects of the disclosure with a tool assembly of the surgical stapling device in an open position;

[0033] FIG. 2 is an enlarged view of a distal portion of the surgical stapling device shown in FIG. 1;

[0034] FIG. 3 is an exploded view of a cartridge assembly of the tool assembly of the surgical stapling device shown in FIG. 1 ;

[0035] FIG. 4 is an enlarged view of the indicated area of detail shown in FIG. 2;

[0036] FIG. 5 is a cross-sectional view taken along section line 6-6 of FIG. 3;

[0037] FIG. 6 is a cross-sectional view taken along a transverse axis of a cartridge body of the cartridge assembly shown in FIG. 3;

[0038] FIG. 7 is a side perspective view of a distal portion of a drive assembly of the surgical stapling device shown in FIG. 1 ;

[0039] FIG. 8 is a side perspective view of the tool assembly of the surgical stapling device shown in FIG. 1 with the tool assembly in the clamped position;

[0040] FIG. 9 is a cross-sectional view taken along section line 9-9 of FIG. 8 illustrating the tool assembly of the surgical stapling device shown in FIG. 1 in a clamped, pre- fired position;

[0041] FIG. 10 is a cross-sectional view taken along the longitudinal axis of the tool assembly of the surgical stapling device shown in FIG. 1 as the surgical stapling device is being fired;

[0042] FIG. 11 is a cross-sectional view taken along section line 11-11 of FIG. 10 with thin tissue clamped between the anvil and the cartridge assembly;

[0043] FIG. 12 is a cross-sectional view taken along a transverse axis of the tool assembly as the surgical stapling device is fired with thicker tissue clamped between the anvil and the cartridge assembly;

[0044] FIG. 13 is a side perspective view of an alternate version of the tool assembly of the stapling device shown in FIG. 1 ;

[0045] FIG. 14 is a side perspective view of the distal portion of the drive assembly of the stapling device shown in FIG. 13;

[0046] FIG. 15 is a cross-sectional view taken along section line 15-15 of FIG. 14;

[0047] FIG. 16 is a perspective view from above of a distal portion of a drive assembly of the stapling device shown in FIG. 13;

[0048] FIG. 17 is a cross-sectional view taken along section line 17-17 of FIG. 16;

[0049] FIG. 18 is a cross-sectional view taken along section line 18-18 of FIG. 13 with the drive assembly advanced to begin firing;

[0050] FIG. 19 is a cross-sectional view taken along section line 19-19 of FIG. 18;

[0051] FIG. 19A is an enlarged view of the indicated area of detail shown in FIG. 19;

[0052] FIG. 20 is a cross-sectional view taken along a longitudinal axis of the tool assembly shown in FIG. 13 with the drive assembly in the drive advanced position with thin tissue clamped between an anvil and a staple cartridge of the tool assembly;

[0053] FIG. 21 is a cross-sectional view taken along the longitudinal axis of the tool assembly shown in FIG. 13 as the drive assembly moves from the drive advanced position towards the drive retracted position with thin tissue clamped between the anvil and the staple cartridge of the tool assembly;

[0054] FIG. 21 A is side view of an alternate version of the distal portion of the working member assembly shown in FIG. 16;

[0055] FIG. 22 is a cross-sectional view taken along the longitudinal axis of the tool assembly shown in FIG. 13 with the drive assembly in the drive advanced position with thicker tissue clamped between the anvil and the staple cartridge of the tool assembly;

[0056] FIG. 23 is a cross-sectional view taken along the longitudinal axis of the tool assembly shown in FIG. 13 as the drive assembly moves from the drive advanced positiontowards the drive retracted position with thicker tissue clamped between the anvil and the staple cartridge of the tool assembly;

[0057] FIG. 24 is a side cross-sectional view of another alternate version of the tool assembly of the stapling device shown in FIG. 1 with thick tissue clamped within the tool assembly; and

[0058] FIG. 25 is side cross-sectional view of the tool assembly shown in FIG. 24 with thinner tissue clamped within the tool assembly.DETAILED DESCRIPTION

[0059] The disclosed surgical stapling device will now be described in detail with reference to the drawings in which like reference numerals designate identical or corresponding elements in each of the several views. However, it is to be understood that the disclosed aspects are merely exemplary of the disclosure and may be embodied in various forms. Well-known functions or constructions are not described in detail to avoid obscuring the disclosure in unnecessary detail. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the disclosure in virtually any appropriately detailed structure.

[0060] In this description, the term “proximal” is used generally to refer to that portion of the device that is closer to a clinician when the device is used in its customary fashion, while the term “distal” is used generally to refer to that portion of the device that is farther from the clinician when the device is used in its customary fashion. In addition, directional terms such as front, rear, upper, lower, top, bottom, and similar terms are used to assist in understanding the description and are not intended to limit the disclosure.

[0061] This disclosure is directed to a surgical stapling device that includes a drive assembly and a tool assembly having an anvil and a cartridge assembly. The cartridge assembly includes a channel member that defines a cavity, and a staple cartridge that is movably supported within the cavity of the channel member between a lowered position and a raised position. The tool assembly is movable from an open position to a clamped position to define a tissue gap between the staple cartridge and the anvil, and the drive assembly is adapted to move the staple cartridge from the lowered position to the raised position to accommodate tissue of different thicknesses.

[0062] FIG. 1 illustrates a surgical stapling device shown generally as stapling device 10 that includes a handle assembly 12, an elongate body or adapter assembly 14, and a tool assembly 16. In aspects of the disclosure, the handle assembly 12 is powered and includes a stationary handgrip 18 and actuation buttons 20. The actuation buttons 20 are operable to actuate various functions of the tool assembly 16 via the adapter assembly 14 including approximation, stapling, and cutting. In certain aspects of the disclosure, the handle assembly 12 supports at least one motor (not shown) and batteries (not shown) that provide power to the handle assembly 12 to operate the stapling device 10. Although the stapling device 10 is illustrated as a powered stapling device, it is envisioned that the tool assembly 16 described is suitable for use with manually powered surgical stapling devices as well as robotically controlled stapling devices.

[0063] The adapter assembly 14 includes a proximal portion 14a and a distal portion 14b. The proximal portion 14a is coupled to the handle assembly 12 and the distal portion 14b supports the tool assembly 16. The tool assembly 16 is coupled to the distal portion 14b of the adapter assembly 14 and includes a cartridge assembly 30 and an anvil 32. The anvil 32 includes a tissue engaging surface 32a (FIG. 11) that defines staple forming pockets (not shown). The cartridge assembly 30 and the anvil 32 are coupled together such that the tool assembly 16 can pivot between an open position (FIG. 1) and a clamped position (FIG. 8). In the clamped position, the anvil 32 and the cartridge assembly 30 are in juxtaposed alignment with each other to define a tissue gap “Gl” (FIG. 9) between the tissue engaging surface 32a of the anvil 32 and the cartridge assembly 30. In aspects of the disclosure, the anvil 32 is stationary and the cartridge assembly 30 pivots in relation to the anvil 32 between the open position and the clamped position. Alternately, it is envisioned that the anvil 32 could be secured to the adapter assembly 14 to pivot in relation to the cartridge assembly 30.

[0064] FIGS. 2-4 illustrate the cartridge assembly 30, which includes a channel member 34 and a staple cartridge 35. The channel member 34 includes side walls 36 and a bottom wall 38 that define a cavity 34a (FIG. 3) having an open end spaced from the bottom wall 38 that receives the staple cartridge 35. The side walls 36 have inner surfaces 39 (FIG. 30) that define planes that are substantially parallel to each other and upper ends (the ends spaced from the bottom wall 38) that have flat surfaces 36a (Fig. 11). The distal portions of the side walls 36 also define recesses 36b. In aspects of the disclosure, the staple cartridge 35 is removably receivedwithin the cavity 34a of the channel member 34 to allow for replacement of the staple cartridge 35 after each firing of the stapling device 10 to facilitate reuse of the stapling device 10 (FIG. 1).

[0065] The staple cartridge 35 (FIG. 3) includes a cartridge body 42, staples 44, pushers 46, an actuation sled 48, and a staple guard 50. The cartridge body 42 of the staple cartridge 35 is received within the cavity 34a defined by the channel member 34 and includes a tissue engaging surface 52 that is juxtaposed alignment with the tissue engaging surface 32a (FIG. 7) of the anvil 32 when the tool assembly 16 is in the clamped position to define the tissue gap. The cartridge body 42 defines a knife slot 54 and a plurality of staple receiving pockets 56 that are arranged in rows on each side of the knife slot 54. In certain aspects of the disclosure, the tissue engaging surface 52 of the staple cartridge 40 has a stepped configuration (FIG. 11) with a raised surface adjacent the knife slot 54 and lower surfaces positioned outwardly of the knife slot 54 towards the side walls 36 of the channel member 34. Each of the staple receiving pockets 56 receives one of the staples 44 (FIG. 3) and at least a portion of one of the pushers 46. In some aspects of the disclosure, the staples 44 in the inner rows of staple receiving pockets 56 are shorter in length than the staples 44 in the outer rows of staple receiving pockets 56. The actuation sled 48 is movable from a sled retracted position towards a sled advanced position into sequential engagement with the pushers 46 to urge the pushers 46 upwardly towards the anvil 32 and eject the staples 44 from the staple receiving pockets 56 of the cartridge body 42.

[0066] The cartridge body 42 includes side walls 60 (FIG. 6) that are positioned on opposite sides of the cartridge body 42 and define axes that extend in a direction parallel to the direction of the knife slot 54. Each of the side walls 60 of the cartridge body 42 includes or supports overhangs 62 that extend outwardly from the tissue engaging surface 52 of the cartridge body 42. The overhangs 62 are fixedly secured to the side walls 60 of the cartridge body 42 and include support surfaces 64 (FIG. 6) that are positioned on a lower portion of the overhangs 62. The support surfaces 64 of the overhangs 62 are positioned to engage the upper flat surfaces 36a of the side walls 36 of the channel member 34 (FIG. 12) as described below to support the staple cartridge 35 within the cavity 34a of the channel member 34.

[0067] The cartridge body 42 includes projections 69 (FIG. 2) that are received within the recesses 36b formed in the side walls 36 of the channel member 34. The projections 69 longitudinally align the staple cartridge 35 within the cavity 34a of the channel member 34 and guide the staple cartridge 35 as the staple cartridge 35 moves vertically within the cavity 34a ofthe channel member 34 between a raised position and a lowered position. In aspects of the disclosure, the projections 69 have slip-resistant outer surfaces, e.g., ridged outer surfaces, that can be gripped by a clinician to facilitate insertion and removal of the staple cartridge 35 into and from the channel member 34.

[0068] The staple guard 50 (FIG. 3) is secured to a bottom side of the cartridge body 42 to retain the staples 44, the pushers 46, and the actuation sled 48 within the cartridge body 42. In aspects of the disclosure, the staple guard 50 includes flexible tabs 50a that define openings that receive protrusions 71 (FIG. 3) formed on an outer surface of the cartridge body 42 to secure the staple guard 50 to the cartridge body 42. In some aspects of the disclosure, the staple guard 50 also includes hooked fingers 50b that engage a proximal portion of the cartridge body 42 to secure a proximal portion of the staple guard 50 to the cartridge body 42 and hooked fingers 50c that engage a distal portion of the cartridge body 42 to secure a proximal portion of the staple guard 50 to the cartridge body 42.

[0069] FIGS. 5 and 6 illustrate the cartridge body 42 of the cartridge assembly 30 which includes inner walls 80 that are spaced from each other to define the knife slot 54. Each of the inner walls 80 has an inner surface that includes a longitudinally extending rail 82 that has a lower support surface 82a that extends along the length of the rail 82. In some aspects of the disclosure, the proximal portion of each of the rails 82 includes an angled cam surface 84 that is contiguous with the lower support surface 82a and is angled upwardly in the proximal direction. In some aspects of the disclosure, each of the inner surfaces of the inner walls 80 of the cartridge body 42 includes a protrusion 86 that extends into the knife slot 54. The protrusions 86 engage the actuation sled 48 (FIG. 3) when the actuation sled 48 is in the sled retracted position to releasably retain the actuation sled 48 in the sled retracted position.

[0070] FIGS. 2 and 7 illustrate a drive assembly 90 of the surgical stapling device 10 (FIG. 1) which includes a flexible beam 92 and a working member 94. The flexible beam 92 is received within the distal portion of the adapter assembly 14 (FIG. 2) and includes a proximal portion 92a that is adapted to be coupled to a drive shaft (not shown) located within the adapter assembly 14 and a distal portion 92b that is secured to the working member 94. In aspects of the disclosure, the flexible beam 92 is formed from laminates 92c although other configurations are envisioned.

[0071] In some aspects of the disclosure, the working member 94 has an I-beam configuration and includes a first beam 96, a second beam 98, and a strut 100 that connects the first beam 96 to the second beam 98. The strut 100 is received within the knife slot 54 (FIG. 6) of the cartridge body 42 and includes or supports a knife 100a. The first beam 96 is received within a longitudinal channel 102 (FIG. 11) defined within the anvil 32, and the second beam 98 is positioned to move along an outer surface of the channel member 34. In aspects of the disclosure, the bottom wall 38 of the channel member 34 has an outer surface that defines a longitudinally extending recess 106 (FIG. 11) that receives the second beam 98 of the working member 94. The drive assembly 90 is movable between a drive retracted position and a drive advanced position to move the tool assembly 16 between the open position and the clamped position and to retain the tool assembly 16 in the clamped position during firing of the surgical stapling device 10. As the drive assembly 90 moves from the drive retracted position towards the drive advanced position, the working member 94 engages the actuation sled 48 of the staple cartridge 35 to advance the actuation sled 48 within the cartridge body 42 into engagement with the pushers 46 to eject the staples 44 from the cartridge body 42.

[0072] The strut 100 includes cam channels 108, one positioned on each side of the strut 100. The cam channels 108 are longitudinally aligned with each other and extend from a distal end of the strut 100 to a proximal end of the strut 100. In aspects of the disclosure, each of the cam channels 108 is defined by a lower wall 108a that includes a distal portion is angled downwardly in the distal direction. The cam channels 108 are dimensioned to receive the rails 82 (FIG. 5) of the cartridge body 42 when the drive assembly 90 is moved from the drive retracted position towards the drive advanced position. The lower walls 108a defining the distal portions of the cam channels 108 are aligned with the angled cam surfaces 84 of the rails 82. When the drive assembly 90 is moved from the drive retracted position towards the drive advanced position, the lower walls 108a defining the cam channels 108 can engage the cam surfaces 84 of the cartridge body 42 to lift the staple cartridge 35 within the cavity 34a of the channel member 34 from a lowered position to a raised position to change the size of the tissue gap defined between the tissue engaging surface 32a of the anvil 32 and the tissue engaging surface 52 of cartridge body 42 of the staple cartridge 32.

[0073] FIGS. 8 and 9 illustrate the tool assembly 16 of the stapling device 10 with the tool assembly 16 in a clamped, pre-fired position. To move the tool assembly 16 to the clamp pre-fired position, the drive assembly 90 is advanced from the drive retracted position to a drive clamped position to move the working member 94 of the drive assembly 90 into engagement with a ramped surface 34b (FIG. 9) of the channel member 34 of the tool assembly 16 to move the tool assembly 16 from the open position to the clamped position. In the drive clamped position of the drive assembly 90, the working member 94 of the drive assembly 90 is spaced proximally of the rails 82 of the cartridge body 42 such that the staple cartridge 35 is seated on the bottom wall 38 of the channel member 34 within the cavity 34a (FIG. 12) to define a maximum tissue gap “Gl” (FIG. 9) between the tissue engaging surface 32a of the anvil 32 and the tissue engaging surface 52 of cartridge body 42 of the staple cartridge 32.

[0074] FIGS. 10 and 11 illustrate the tool assembly 16 of the stapling device 10 with the tool assembly 16 in the clamped position as the stapling device 10 is fired with thin tissue. When the drive assembly 90 is advanced from the drive clamped position towards the drive advanced position in the direction indicated by arrow “A” in FIG. 10, the working member 94 of the drive assembly 90 is advanced through the staple cartridge 35 to advance the actuation sled 48 (FIG. 3) from the sled retracted position towards the sled advanced position. As the working member 94 moves through the cartridge body 42 of the staple cartridge 35, the strut 100 of the working member 94 moves to a position in which the angled distal portion of the walls 108a defining the cam channels 108 of the working member 94 engage the angled cam surfaces 84 of the rails 82. When the distal angled portion of the lower walls 108a defining the cam channels 108 engage the angled cam surfaces 84 of the rails 82 with the thin tissue (Tl) clamped within the tool assembly 16, the staple cartridge 35 is cammed upwardly within the cavity 34a (FIG. 3) of the channel member 34 towards the anvil 32 in the direction indicated by arrows “B” in FIGS. 10 and 11 to decrease the size of the tissue gap defined between the tissue engaging surface 32a of the anvil 32 and the tissue engaging surface 52 of cartridge body 42 of the staple cartridge 35 from the maximum tissue gap “Gl” (FIG. 9) to the minimum tissue gap “G2” (FIG. 10). When thin tissue is clamped between the tissue engaging surface 32a of the anvil 32 and the tissue engaging surface 52 of cartridge body 42 of the staple cartridge 32, the lower support surfaces 82a of the rails 82 of the staple cartridge 35 are supported on the lower walls 108a defining the cam channels 108 of the strut 100 of the working member 94 to support the staple cartridge 35 in a raised position within the cavity 34a of the channel member 34 of the cartridge assembly 35 with the staple guard 50 positioned above the bottom wall 38 of the channel member 34 and thesupport surfaces 64 of the overhangs of the cartridge body 42 positioned above the flat surfaces 36a of the channel member 34.

[0075] FIG. 12 illustrates the tool assembly 16 of the surgical stapling device 10 with the tool assembly 16 in the clamped position as the stapling device 10 is fired with thicker tissue. When the drive assembly 90 is advanced from the drive clamped position towards the drive advanced position, the working member 94 of the drive assembly 90 is advanced through the staple cartridge 35 to advance the actuation sled 48 from the sled retracted position towards the sled advanced position. As the working member 94 moves through the cartridge body 42 of the staple cartridge 35, the strut 100 of the working member 94 moves to a position in which the angled distal portion of the walls 108a defining the cam channels 108 engage the angled cam surfaces 84 of the rails 82 but the thick tissues presses the staple cartridge 35 downwardly in the direction indicated by arrows “C” in FIG. 12 to prevent the staple cartridge 35 from moving upwardly within the cavity 34a of the channel member 34. As the working member 94 is advanced, engagement between the strut 100 of the working member 94 and the longitudinally extending rails 82 of the staple cartridge 35 deforms or shears the longitudinally extending rails 82 on or from the staple cartridge 35 such that the staple cartridge 35 remains in the lowered position within the cavity 34a of the channel member 34. As such, the size of the tissue gap “Gl” does not change or does not change substantially. It is envisioned that only a portion of the longitudinally extending rails 82 can be deformed or sheared by the strut 100 such that the size of the tissue gap can be any size between and including tissue gaps “Gl” and “G2” In aspects of the disclosure the size of the tissue gap can vary from between about .010 inch and about .080 inch depending on the thickness of the tissue being treated by the tool assembly 16.

[0076] FIG. 13 illustrates an alternate version of the tool assembly of the stapling device 10 (FIG. 1) shown generally as tool assembly 216. The tool assembly 216 includes a cartridge assembly 230 and an anvil 232. The anvil 232 is like the anvil 32 (FIG. 1) and will not be described in further detail herein. The cartridge assembly 230 includes a channel member 234 and a staple cartridge 235. The staple cartridge 235 is like the staple cartridge 35 (FIG. 3) except for minor changes which are described in further detail below.

[0077] FIGS. 14 and 15 illustrate the channel member 234 which includes side walls 236 and a bottom wall 238 that define a cavity 234a having an open end spaced from the bottom wall 238 that receives the staple cartridge 235. The side walls 236 have inner surfaces 239 (FIG. 14)that define planes that are substantially parallel to each other and upper ends (the ends spaced from the bottom wall 238) that have flat surfaces 236a (Fig. 14). The distal portions of the side walls 236 also define recesses 236b. In aspects of the disclosure, the staple cartridge 235 is removably received within the cavity 234a of the channel member 234 to allow for replacement of the staple cartridge 235 after each firing to facilitate reuse of the stapling device 10 (FIG. 1).

[0078] The bottom wall 238 of the channel member 234 defines a knife slot 234b and supports clamp adjustment members 240 that are positioned on opposite sides of and longitudinally aligned with the knife slot 234b. Each of the clamp adjustment members 240 includes an upper guide surface 240a and a lower guide surface 240b and is spaced upwardly from the bottom wall 238 of the channel member 234 to define elongate slots 242 (FIG. 15) between the lower guide surfaces 240b of the clamp adjustment members 240 and the bottom wall 238 of the channel member 234. The distal end portions 240c of the clamp adjustment members 240 have angled upper and lower cam surfaces. In aspects of the disclosure, the clamp adjustment members 240 have proximal portions 246 that are secured to the bottom wall 238 of the channel member 234 in cantilevered fashion.

[0079] FIGS. 16 and 17 illustrate a drive assembly 290 of the surgical stapling device 10 (FIG. 1). The drive assembly 290 is like the drive assembly 90 (FIG. 7) and includes a flexible beam 292 and a working member assembly 294. The flexible beam 292 is received within the distal portion of the adapter assembly 14 (FIG. 2) and includes a proximal portion (not shown) that is adapted to be coupled to a drive shaft (not shown) located within the adapter assembly 14 and a distal portion 292b that is secured to the working member assembly 294. In aspects of the disclosure, the flexible beam 292 is formed from laminates 292c although other configurations are envisioned.

[0080] The working member assembly 294 includes a body 294a having an I-beam configuration and including a first beam 296, a second beam 298, and a strut 300 that connects the first beam 296 to the second beam 298. The strut 300 is received within the knife slot 254 (FIG. 19) of the cartridge body 256 of the staple cartridge 235 and includes or supports a knife 300a. The first beam 296 is received within a longitudinal channel 302 (FIG. 11) defined within the anvil 232, and the second beam 298 is positioned to move along an outer surface 319 (FIG. 19) of the channel member 234. In aspects of the disclosure, the bottom wall 238 of the channel member 234 has an outer surface that defines a longitudinally extending recess 306 (FIG. 19)that receives the second beam 298 of the body 294a of the working member 294. The drive assembly 290 is movable between a drive retracted position and a drive advanced position to move the tool assembly 216 between the open position and the clamped position and to retain the tool assembly 216 in the clamped position during firing of the surgical stapling device 10 (FIG. 1). As the drive assembly 290 moves from the drive retracted position towards the drive advanced position, the body 294a of the working member 294 engages an actuation sled (not shown) of the staple cartridge 235 (FIG. 19) to advance the actuation sled within the cartridge body 256 into engagement with pushers 260 to eject staples 262 from the cartridge body 256.

[0081] The strut 300 of the body 294a of the working member assembly 294 defines two transverse, elongate slots 304 (FIG. 17) and channels 306 that extend from each of the elongate slots 304 to a position adjacent the second beam 298. Each of the elongate slots 304 receives a pin 308 that extends outwardly from opposite sides of the elongate slot 304 and is positioned to engage the clamp adjustment members 240 of the channel member 234 as described below. Biasing members 310 (FIG. 17) are received within the channels 306 of the strut 300 and are engaged with the pins 308 to urge the pins 308 downwardly towards the ends of the elongate slots 304 closest to the second beam 298. In aspects of the disclosure, each of the biasing members 310 is in the form of a coil spring that has a first end 310a coupled to one of the pins 308 and a second end 310b secured to the body 294a of the working member assembly 294.

[0082] FIGS. 18 and 19 illustrate the tool assembly 216 as the drive assembly 290 is advanced to fire staples 262 from the staple cartridge 235. When the stapling device 10 (FIG. 1) is fired, the pins 308 are positioned on and move along the upper guide surfaces 240a of the clamp adjustment members 240 as the working member assembly 294 moves from the drive retracted position towards the drive advanced position. Since the pins 308 are positioned on the upper guide surfaces 240a of the clamp adjustment members 240 in the upper ends of the elongate slots 304 of the strut 300, the tissue gap “Gl” defined between the staple cartridge 235 and the anvil 232 is controlled by the distance between the first beam 296 and the second beam 298. It is noted that the biasing members 310 are in tension and are pulling the pins 308 towards the lower ends of the elongate slots 304. When the pushers 260 are sequentially moved upwardly to their raised positions by the actuation sled 258 (FIG. 19A), the pushers 260 are retained in their raised positions by detents 350 formed on the pushers 260 that are received in pockets 352 defined in the cartridge body 256 of the staple cartridge 235.

[0083] FIGS. 20 and 21 illustrate the tool assembly 216 as the drive assembly 290 is returned from the drive advanced position to the drive retracted position after the stapling device 10 (FIG. 1) has been fired with thin tissue clamped between the staple cartridge 235 and the anvil 232. When the drive assembly 290 is moved to the drive advanced position in the direction indicated by arrow “D” in FIG. 20 (with thin tissue or thicker tissue), the pins 308 of the working member assembly 294 pass off a distal end of the clamp adjustment members 240 and are pulled downwardly to the lower ends of the elongate slots 304 of the strut 300 of the body 294a of the working member assembly 294 in the direction indicated by arrow “E” in FIG. 20. As the drive assembly 290 moves from the drive advanced position towards the drive retracted position in the direction indicated by arrow “F” in FIG. 21, the pins 308 which are aligned with the lower guide surfaces 240b of the clamp adjustment members 240 engage the distal end portions 240c of the clamp adjustment members 240 and are cammed downwardly onto the lower guide surfaces 240b of the clamp adjustment members 240 to urge the cartridge assembly 230 upwardly towards the anvil 232 in the direction of arrow “G” in FIG. 21 to decrease the size of the tissue gap “G2”. Since the pushers (FIG. 19A) are retained in their raised positions, the upward movement of the cartridge assembly 235 in relation to the anvil 232 causes further formation of the staples 262 such that the size of the tissue gap “G2” decreases.

[0084] FIG. 21 A illustrates an alternate version of the working member assembly shown generally as working member assembly 294’. The working member assembly 294’ is like the working member assembly 294 except that the strut 300’ of the body 294a’ of the working member assembly 294’ include a notch 301 ’ that communicates with the lower ends of the elongate slots 304’. When the pins 308’ are positioned at the lower ends of the elongate slots 304’, the pins 308’ are received within the notches 301 ’ to retain the pins 308’ in the lower ends of the elongate slots 304’. In some aspects of the disclosure, a biasing member 303’ is supported on the strut 300’to urge the pins 308’ into the notches when the pins are positioned in the lower ends of the elongate slots 304’.

[0085] FIGS. 22 and 23 illustrate the tool assembly 216 as the drive assembly 290 is returned from the drive advanced position to the drive retracted position after the stapling device 10 (FIG. 1) has been fired with thicker tissue clamped between the staple cartridge 235 and the anvil 232. When the drive assembly 290 is moved to the drive advanced position in the direction indicated by arrow “H” in FIG. 22 (with thin tissue or thicker tissue), the pins 308 of the working memberassembly 294 pass off a distal end of the clamp adjustment members 240 and are pulled downwardly to the lower ends of the elongate slots 304 of the strut 300 of the body 294a of the working member assembly 294 in the direction indicated by arrow “I” in FIG. 22. The thicker tissue causes the pins 308 of the working member assembly 290 to be aligned with the upper guide surfaces 240a of the clamp adjustment members 240. As the drive assembly 290 moves from the drive advanced position towards the drive retracted position in the direction indicated by arrow “F” in FIG. 23, the pins 308 engage an upper surface of the distal end portions 240c of the clamp adjustment members 240 and are cammed upwardly onto the upper guide surfaces 240a of the clamp adjustment members 240 to urge the cartridge assembly 230 downwardly away from the anvil 232 in the direction of arrow “J” in FIG. 23 to increase the size of the tissue gap “Gl”

[0086] FIGS. 24 and 25 illustrate an alternate version of the tool assembly of the stapling device 10 (FIG. 1) shown generally as tool assembly 416. The tool assembly 416 is like the tool assembly 216 and includes a cartridge assembly 430 and an anvil 432 that are like the anvil 232 (FIG. 13) and the cartridge assembly 230 and will not be described in further detail herein. The drive assembly 490 differs from the drive assembly 290 in that the working member assembly 494 includes pins 508 that are fixedly secured to the strut 500 of the working member assembly 494.

[0087] The tool assembly 416 when fired functions in a manner like the tool assembly 216. More specifically, when the drive assembly 490 is moved in the direction indicated of arrow “G” in FIG. 24 from the drive retracted position towards the drive advanced position, the pins 508 are positioned on and move along the upper guide surfaces 440a of the clamp adjustment members 440. If thick tissue is clamped between the anvil 432 and the cartridge assembly 430, the pins 508 will remain on the upper guide surfaces 440a of the clamp adjustment members 440 as the drive assembly 490 moves from the drive advanced position back towards the drive retracted position. If thinner tissue is clamped between the anvil 432 and the cartridge assembly 430, the pins 508 will be directed by the distal ends 440c of the clamp adjustment members 440 onto the lower guide surfaces 440b of the clamp adjustment members 440 to urge the cartridge assembly 430 upwardly towards the anvil 432 as described above to decrease the size of the tissue gap.

[0088] Persons skilled in the art will understand that the devices and methods specifically described herein and illustrated in the accompanying drawings are non-limiting exemplaryaspects of the disclosure. It is envisioned that the elements and features illustrated or described in connection with one exemplary aspect of the disclosure may be combined with the elements and features of another without departing from the scope of the disclosure. Also, one skilled in the art will appreciate further features and advantages of the disclosure based on the above-described aspects of the disclosure. Accordingly, the disclosure is not to be limited by what has been particularly shown and described, except as indicated by the appended claims.

[0089] The following examples are illustrative of the techniques described herein.

[0090] Example 1. A tool assembly comprising: an anvil having a tissue engaging surface; a cartridge assembly coupled to the anvil to facilitate movement of the tool assembly between an open position and a clamped position, the cartridge assembly including a channel member and a staple cartridge, the channel member having side walls and a bottom wall that together define a cavity, the staple cartridge supported within the cavity of the channel member and having a tissue engaging surface that is spaced from the tissue engaging surface of the anvil when the tool assembly is in the clamped position to define a tissue gap, the staple cartridge having a cartridge body that defines a knife slot and staple receiving pockets positioned on each side of the knife slot, the cartridge body including inner walls that define the knife slot, at least one of the inner walls having a longitudinally extending rail, the staple cartridge movable within the cavity of the channel member between a lowered position and a raised position to change the size of the tissue gap; and a drive assembly including a working member including a first beam, a second beam, and a strut that connects the first beam to the second beam, the strut received within the knife slot and defining at least one cam channel, the drive assembly movable from a drive retracted position to a drive advanced position to move the working member through the cartridge body, wherein the at least one cam channel is positioned to receive the at least one longitudinally extending rail of the cartridge body to move the staple cartridge from the lowered position to the raised position within the cavity of the channel member.

[0091] Example 2. The tool assembly of example 1 , wherein the at least one longitudinally extending rail includes two longitudinally extending rails, one of the two longitudinally extending rails positioned on the cartridge body on each side of the knife slot.

[0092] Example 3. The tool assembly of example 2, wherein the at least one cam channel includes two cam channels, each of the two cam channels positioned to receive one of the two longitudinally extending rails.

[0093] Example 4. The tool assembly of example 1, wherein the at least one cam channel is defined by a lower wall having a distal portion that is angled downwardly in the distal direction.

[0094] Example s. The tool assembly of example 1 , wherein the at least one longitudinally extending rail is configured to be deformed by the strut of the working member when a predetermined force is applied to the staple cartridge in a direction towards the bottom wall of the channel member.

[0095] Example 6. The tool assembly of example 1 , wherein the at least one longitudinally extending rail is configured to be sheared from the cartridge body by the strut of the working member when a predetermined force is applied to the staple cartridge in a direction towards the bottom wall of the channel member.

[0096] Example 7. The tool assembly of example 1, wherein the staple cartridge includes staples, pushers, and an actuation sled, the staples and pushers received in the staple receiving pockets, the actuation sled movable through the cartridge body from a sled retracted position towards a sled advanced position to eject the staples from the cartridge body.

[0097] Example 8. A stapling device comprising: a handle assembly; an adapter assembly having a proximal portion and a distal portion, the proximal portion coupled to the handle assembly; and a tool assembly supported on the distal portion of the adapter assembly, the tool assembly including: an anvil having a tissue engaging surface; a cartridge assembly coupled to the anvil to facilitate movement of the tool assembly between an open position and a clamped position, the cartridge assembly including a channel member and a staple cartridge, the channel member having side walls and a bottom wall that together define a cavity, the staple cartridge supported within the cavity of the channel member and having a tissue engaging surface that is spaced from the tissue engaging surface of the anvil when the tool assembly is in the clamped position to define a tissue gap, the staple cartridge having a cartridge body that defines a knife slot and staple receiving pockets positioned on each side of the knife slot, the cartridge body including inner walls that define the knife slot, at least one of the inner walls having a longitudinally extending rail, the staple cartridge movable within the cavity of the channel member between a lowered position and a raised position to change the size of the tissue gap; and a drive assembly including a working member including a first beam, a second beam, and a strut that connects the first beam to the second beam, the strut received within the knife slot anddefining at least one cam channel, the drive assembly movable from a drive retracted position to a drive advanced position to move the working member through the cartridge body, wherein the at least one cam channel is positioned to receive the at least one longitudinally extending rail of the cartridge body to move the staple cartridge from the lowered position to the raised position within the cavity of the channel member.

[0098] Example 9. The stapling device of example 8, wherein the at least one longitudinally extending rail includes two longitudinally extending rails, one of the two longitudinally extending rails positioned on the cartridge body on each side of the knife slot, and the at least one cam channel includes two cam channels, each of the two cam channels positioned to receive one of the two longitudinally extending rails.

[0099] Example 10. A tool assembly comprising: an anvil having a tissue engaging surface; a cartridge assembly coupled to the anvil to facilitate movement of the tool assembly between an open position and a clamped position, the cartridge assembly including a channel member and a staple cartridge, the channel member defining a channel knife slot and having side walls and a bottom wall that together define a cavity, the bottom wall of the channel member supporting at least one clamp adjustment member, the at least one clamp adjustment member having at least one guide surface, the staple cartridge supported within the cavity of the channel member and having a tissue engaging surface that is spaced from the tissue engaging surface of the anvil when the tool assembly is in the clamped position to define a tissue gap, the staple cartridge movable within the cavity of the channel member between a lowered position and a raised position and having a cartridge body that defines a cartridge knife slot and staple receiving pockets positioned on each side of the cartridge knife slot; and a drive assembly including a working member assembly having a body and at least one pin, the body of the working member assembly including a first beam, a second beam, and a strut that connects the first beam to the second beam, the strut received within the cartridge knife slot and the channel knife slot, the drive assembly movable from a drive retracted position to a drive advanced position to move the working member through the cartridge body, wherein the at least one pin is positioned to engage the at least one guide surface to move the staple cartridge from the lowered position to the raised position within the cavity of the channel member.

[0100] Example 11. The tool assembly of examplelO, wherein the strut defines at least one elongate slot, the at least one pin extending through the at least one elongate slot.

[0101] Example 12. The tool assembly of example 11, wherein the working member assembly further includes at least one biasing member coupled to the at least one pin, and the at least one elongate slot includes a first end and a second end, the biasing member positioned urge the at least one pin towards the second end of the at least one elongate slot.

[0102] Example 13. The tool assembly of example 12, wherein the at least one elongate slot includes two elongate slots, the at least one pin includes two pins, and the at least one biasing member includes two biasing members.

[0103] Example 14. The tool assembly of example 13, wherein the at least one clamp adjustment member includes a first clamp adjustment member supported on the bottom wall of the channel member on a first side of the channel knife slot and a second clamp adjustment member positioned on a second side of the channel knife slot, each of the two pins engaged with the first clamp adjustment member and the second clamp adjustment member.

[0104] Example 15. The tool assembly of example 10, wherein the at least one guide surface includes an upper guide surface and a lower guide surface, the at least one pin movable into engagement with the lower guide surface to move the staple cartridge from the lowered position to the raised position.

[0105] Example 16. The tool assembly of example 15, wherein the at least one clamp adjustment member includes a distal end portion having an angled upper cam surface and an angled lower cam surface, the angled upper cam surface directing the at least one pin into engagement with the upper guide surface and the angled lower cam surface directing the at least one pin into engagement with the lower guide surface.

[0106] Example 17. The tool assembly of example 16, wherein the staple cartridge includes staples, pushers and an actuation sled, the staples and pushers received within the staple receiving slots of the cartridge body, the actuation sled movable from a sled retracted position to a sled advanced position into sequential engagement with the pushers to move the pushers from a pusher lowered position to a pusher raised position to eject the staples from the staple cartridge into the anvil to form the staples.

[0107] Example 18. The tool assembly of example 17, wherein the at least one pin is movable into engagement with the lower guide surfaces of the first clamp adjustment member and the second adjustment member when the drive assembly is moved from the drive advanced 1position towards the drive retracted position to move the staple cartridge from the lowered position to the raised position to further form the staples.

[0108] Example 19. The tool assembly of example 18, wherein the pushers include detents to retain the pushers in the pusher raised position.

[0109] Example 20. The tool assembly of examplel9, wherein the cartridge body of the staple cartridge defines pockets that receive the detents.

Claims

WHAT IS CLAIMED IS:

1. A tool assembly (16) comprising: an anvil (32) having a tissue engaging surface (32a); a cartridge assembly (30) coupled to the anvil (32) to facilitate movement of the tool assembly (16) between an open position and a clamped position, the cartridge assembly (30) including a channel member (34) and a staple cartridge (35), the channel member (34) having side walls (36) and a bottom wall (38) that together define a cavity (34a), the staple cartridge (35) supported within the cavity (34a) of the channel member (34) and having a tissue engaging surface (52) that is spaced from the tissue engaging surface (32a) of the anvil (32) when the tool assembly (16) is in the clamped position to define a tissue gap, the staple cartridge (35) having a cartridge body (42) that defines a knife slot (54) and staple receiving pockets (56) positioned on each side of the knife slot (54), the cartridge body (42) including inner walls (80) that define the knife slot (54), at least one of the inner walls (80) having a longitudinally extending rail (82), the staple cartridge (35) movable within the cavity (34a) of the channel member (34) between a lowered position and a raised position to change the size of the tissue gap; and a drive assembly (90) including a working member (94) including a first beam (96), a second beam (98), and a strut (100) that connects the first beam (96) to the second beam (98), the strut (100) received within the knife slot (54) and defining at least one cam channel (108), the drive assembly (90) movable from a drive retracted position to a drive advanced position to move the working member (94) through the cartridge body (42), wherein the at least one cam channel (108) is positioned to receive the at least one longitudinally extending rail (82) of the cartridge body (42) to move the staple cartridge (35) from the lowered position to the raised position within the cavity (34a) of the channel member (34).

2. The tool assembly (16) according to claim 1, wherein the at least one longitudinally extending rail (82) includes two longitudinally extending rails (82), one of the two longitudinally extending rails (82) positioned on the cartridge body (42) on each side of the knife slot (54).

3. The tool assembly (16) according to claim 2, wherein the at least one cam channel (108) includes two cam channels (108), each of the two cam channels (108) positioned to receive one of the two longitudinally extending rails (82).

4. The tool assembly (16) according to any of the preceding claims, wherein the at least one cam channel (108) is defined by a lower wall (108a) having a distal portion that is angled downwardly in the distal direction.

5. The tool assembly (16) according to any of the preceding claims, wherein the at least one longitudinally extending rail (82) is configured to be deformed by the strut (100) of the working member (94) when a predetermined force is applied to the staple cartridge (35) in a direction towards the bottom wall (38) of the channel member (34).

6. The tool assembly (16) according to any of the preceding claims, wherein the at least one longitudinally extending rail (82) is configured to be sheared from the cartridge body (42) by the strut (100) of the working member (94) when a predetermined force is applied to the staple cartridge (35) in a direction towards the bottom wall (38) of the channel member (34).

7. The tool assembly (16) according to any of the preceding claims, wherein the staple cartridge (35) includes staples (44), pushers (46), and an actuation sled (48), the staples (44) and the pushers (46) received in the staple receiving pockets (56), the actuation sled (48) movable through the cartridge body (42) from a sled retracted position towards a sled advanced position to eject the staples (44) from the cartridge body (42).

Images