Patent Description:
Examples of endoscopic surgical instruments include surgical staplers. Some such staplers are operable to clamp down on layers of tissue, cut through the clamped layers of tissue, and drive staples through the layers of tissue to substantially seal the severed layers of tissue together near the severed ends of the tissue layers.

While the surgical staplers referred to above are described as being used in endoscopic procedures, it should be understood that such surgical staplers may also be used in open procedures and/or other non-endoscopic procedures. By way of example only, a surgical stapler may be inserted through a thoracotomy, and thereby between a patient's ribs, to reach one or more organs in a thoracic surgical procedure that does not use a trocar as a conduit for the stapler. Such procedures may include the use of the stapler to sever and close a vessel leading to a lung. For instance, the vessels leading to an organ may be severed and closed by a stapler before removal of the organ from the thoracic cavity. Of course, surgical staplers may be used in various other settings and procedures.

In some instances, it may be desirable to equip a surgical stapling instrument with a buttress material to reinforce the mechanical fastening of tissue provided by staples. Such a buttress may prevent the applied staples from pulling through tissue and may otherwise reduce a risk of tissue tearing at or near the site of applied staples. Such buttress material may be applied to the surgical stapling instrument with a buttress applier cartridge. The buttress applier cartridge retains the buttress material prior to application and releases the buttress material once applied to the surgical stapling instrument. An example of such buttress applier cartridge is disclosed in <CIT>.

<CIT> describes a buttress applied to an end effector of a surgical stapler. The buttress is loaded on a platform of a buttress applier cartridge, and secured to the end effector by an adhesive layer. <CIT> describes an apparatus including a housing, a platform and a buttress assembly. The platform is configured to apply at least two different amounts of pressure against a first buttress assembly in response to a clamping action of an end effector positioned in a gap defined by the housing.

The invention is defined by the independent claim.

It should be understood that terms such as "proximal" and "distal" are used herein with reference to a clinician gripping a surgical instrument, such as surgical and severing instrument (<NUM>) and buttress applier cartridge assembly (<NUM>) discussed below. It will be further appreciated that for convenience and clarity, spatial terms such as "left," "right," "front," "rear," "upright," "upside-down," "upper," "lower," "bottom," and "top" are used herein with respect to the drawings. However, surgical instruments are used in many orientations and positions, and these terms are not intended to be limiting and absolute.

In some instances, it may be desirable to use an exemplary buttress applier cartridge assembly (<NUM>) as shown in <FIG> to equip a surgical instrument with a buttress assembly (<NUM>) for forming staples in tissue with a buttress (<NUM>). Such buttress (<NUM>) inhibits the formed staples from pulling through the tissue to thereby reduce a risk of tissue tearing at or near the site of formed staples. In addition to or as an alternative to providing structural support and integrity to a line of staples, buttress (<NUM>) may provide various other kinds of effects such as spacing or gap-filling, administration of therapeutic agents, and/or other effects. Prior to use with the surgical instrument, one or more buttresses (<NUM>) is releasably retained on a buttress applier cartridge (<NUM>), which is configured to deposit buttress assembly (<NUM>) onto surgical instrument for use as discussed below in more detail in an exemplary surgical instrument (<NUM>) (see FIG.

<FIG> shows buttress applier cartridge assembly (<NUM>) including a pair of buttress assemblies (<NUM>) releasably retained on buttress applier cartridge (<NUM>), which supports and protects buttress assemblies (<NUM>) prior to use and further aids with loading buttress assemblies (<NUM>) on surgical instrument (<NUM>) (see FIG. Buttress applier cartridge (<NUM>) of the present example includes an open end (<NUM>) and a closed end (<NUM>). Open end (<NUM>) is configured to receive end effector (<NUM>) (see FIG. 10A) as described below in greater detail. Buttress applier cartridge (<NUM>) further includes a housing assembly (<NUM>) having an upper housing (<NUM>) and a lower housing (<NUM>), which each generally define a "U" shape to present open end (<NUM>). Various components are interposed between upper and lower housings (<NUM>, <NUM>). In particular, these components include a platform (<NUM>) supporting a chassis (<NUM>).

Platform (<NUM>) of the present example supports upper buttress assembly (<NUM>) on one side of platform (<NUM>) and lower buttress assembly (<NUM>) on the other side of platform (<NUM>). Platform (<NUM>) is exposed in recesses that are formed between the prongs of the "U" configuration of upper and lower housings (<NUM>, <NUM>). Thus, upper housing (<NUM>) has an upper gap (<NUM>) extending to the open end (<NUM>) along an upper surface of platform (<NUM>), and lower housing (<NUM>) similarly has a lower gap (<NUM>) extending to the open end (<NUM>) along the lower surface of platform (<NUM>). The location of platform (<NUM>) and buttress assemblies (<NUM>) in such recesses may prevent inadvertent contact between buttress assemblies (<NUM>) and other devices in the operating room. In other words, upper and lower housings (<NUM>, <NUM>) may provide some degree of physical shielding of buttress assemblies (<NUM>) while buttress assemblies are retained on platform (<NUM>).

Additional features may be combined as applicable with the following example of buttress applier cartridge assembly (<NUM>). Such features are described in <CIT>, entitled "Adhesive Distribution on Buttress for Surgical Stapler," filed on even date herewith; <CIT>, entitled "Surgical Stapler Buttress with Tissue In-Growth Promotion," filed on even date herewith; <CIT>, entitled "Configuration of Buttress for Surgical Stapler," filed on even date herewith; <CIT>, entitled "Packaging for Surgical Stapler Buttress," filed on even date herewith; <CIT>, entitled "Method of Applying Buttresses to Surgically Cut and Stapled Sites," filed on even date herewith; <CIT>, entitled "Curved Tip Surgical Stapler Buttress Assembly Applicator with Opening Feature for Curved Tip Alignment," filed on even date herewith; <CIT>, entitled "Curved Tip Surgical Stapler Buttress Assembly Applicator with Proximal Alignment Features," filed on even date herewith; and <CIT>, entitled "Curved Tip Surgical Stapler Buttress Assembly Applicator with Compression Layer Pocket Feature," filed on even date herewith; <CIT>, entitled "Applicator for a Surgical Stapler Buttress," filed on even date herewith; <CIT>, entitled "Buttress for Surgical Stapler," filed on even date herewith; <CIT>, entitled "Tray for Surgical Stapler Buttress Applicator," filed on even date herewith; <CIT>, entitled "Applicator for a Surgical Stapler Buttress," filed on even date herewith; and <CIT>, entitled "Buttress Assembly for a Surgical Stapler," filed on even date herewith.

With respect to <FIG>, upper and lower buttress assemblies (<NUM>) are structurally identical, but for the relative positions of upper and lower buttress assemblies (<NUM>) retained on buttress applier cartridge (<NUM>). Buttress applier cartridge assembly (<NUM>) may thus be used in more than one orientation with surgical instrument (<NUM>) (see <FIG>). It will be appreciated that the following description of upper buttress assembly (<NUM>) similarly applies to lower buttress assembly (<NUM>) but for the respective orientations.

Upper buttress assembly (<NUM>) includes buttress (<NUM>) and an upper adhesive layer (<NUM>). Buttress (<NUM>) of the present example more particularly has a three-layer, polymer construction including a core layer sandwiched between two outer layers to be collectively strong yet flexible to support a line of staples. In the present example, core layer is a polyglactin <NUM> material, which is manufactured and sold by Ethicon, Inc. of Somerville, New Jersey as VICRYL, whereas each outer layer is a polydioxanone (PDO) film material. Buttress (<NUM>) of the present example is formed by laminating core layer between outer layers under a predetermined pressure, a predetermined temperature, and a predetermine time. Buttress (<NUM>) is further mechanically cut to size thereby inhibiting abrasive edges, such as burrs and/or delamination, that could damage sensitive tissues. It will be appreciated that alternative methods of cutting buttresses (<NUM>), such as a laser cutting or hot knife cutting, may be similarly used.

By way of further example only, each buttress (<NUM>) may comprise one or more of the following: NEOVEIL absorbable PGA felt by Gunze Limited, of Kyoto, Japan; SEAMGUARD polyglycolic acid: trimethylene carbonate (PGA:TMC) reinforcement material by W. Gore & Associates, Inc. , of Flagstaff, Arizona; PERI-STRIPS DRY with VERITAS Collagen Matrix (PSDV) reinforcement material, by Baxter Healthcare Corporation of Deerfield, Illinois; BIODESIGN biologic graft material by Cook Medical, Bloomington, Indiana; and/or SURGICEL NU-KNIT hemostat material by Ethicon, Inc. of Somerville, New Jersey. Still other suitable materials that may be used to form each buttress (<NUM>) will be apparent to those of ordinary skill in the art in view of the teachings herein.

In addition or in the alternative, each buttress (<NUM>) may comprise a material including, for example, a hemostatic agent such as fibrin to assist in coagulating blood and reduce bleeding at the severed and/or stapled surgical site along tissue. As another merely illustrative example, each buttress (<NUM>) may comprise other adjuncts or hemostatic agents such as thrombin may be used such that each buttress (<NUM>) may assist to coagulate blood and reduce the amount of bleeding at the surgical site. Other adjuncts or reagents that may be incorporated into each buttress (<NUM>) may further include but are not limited to medical fluid or matrix components. Merely illustrative examples of materials that may be used to form each buttress (<NUM>), as well as materials that may be otherwise incorporated into each buttress (<NUM>), are disclosed in <CIT>. Alternatively, any other suitable materials may be
used.

By way of further example only, each buttress (<NUM>) may be constructed in accordance with at least some of the teachings of <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; and/or <CIT>.

Furthermore, buttress (<NUM>) is configured to be cut by a knife (not shown) from a proximal portion of buttress (<NUM>), along an intermediate portion of buttress (<NUM>), and further through a distal portion of buttress (<NUM>) such that inward edges are adjacent to cut tissue as discussed below in more detail. Buttress (<NUM>) further includes a longitudinally extending pre-cut slit (<NUM>) configured to receive knife (not shown) and aid in separating lateral portions of buttress (<NUM>) as inward edges form therealong.

Upper adhesive layer (<NUM>) is provided on outer layer of buttress (<NUM>) in order to adhere buttress (<NUM>) within effector (<NUM>) (see <FIG>) of surgical instrument (<NUM>) (see <FIG>). Adherence of the buttress (<NUM>) can occur through a variety of mechanisms including but not limited to a pressure sensitive adhesive. In the case of pressure sensitive adhesion, adhesion occurs upon the application of at least a predetermined minimum force. In some versions, each adhesive layer (<NUM>) includes a pressure sensitive adhesive material. Examples of various suitable materials that may be used to form adhesive layers (<NUM>) are disclosed in <CIT>. Alternatively, any other suitable materials may be used. As shown in the present example, adhesive layer (<NUM>) is applied to form a continuous outer seal to enhance longevity once applied to end effector (<NUM>) (see <FIG>).

It should be understood that the term "adhesive," as used herein, may include (but is not limited to) tacky materials and also materials that are pliable or wax-like and adhere to a complex geometry via deformation and conformance. Some suitable adhesives may provide such pliability to adhere to a complex geometry via deformation and conformance without necessarily providing a high initial tack. In some instances, adhesives with lower tackiness may be removed more cleanly from surfaces. Various suitable materials that may be used to form adhesive layers (<NUM>) will be apparent to those of ordinary skill in the art in view of the teachings herein.

As shown in <FIG>, buttress applier cartridge (<NUM>) includes chassis (<NUM>) supporting platform (<NUM>) as well as upper and lower housings (<NUM>, <NUM>) of housing assembly (<NUM>) configured to connect together to define an interior space (<NUM>). An upper left actuator sled (<NUM>) and an upper right actuator sled (<NUM>) are movably connected to an upper face chassis (<NUM>) within interior space (<NUM>), while a lower left actuator sled (<NUM>) and a lower right actuator sled (<NUM>) are movably connected to a lower face of chassis (<NUM>) within interior space (<NUM>). Upper right and left actuator sleds (<NUM>, <NUM>) retain upper buttress assembly (<NUM>) on platform (<NUM>) in a restraint position, but are configured to move from the restraint position to a release position for depositing the upper buttress assembly (<NUM>) on end effector (<NUM>) (see <FIG>). Similarly, lower right and left actuator sleds (<NUM>, <NUM>) retain lower buttress assembly (<NUM>) on platform (<NUM>) in the restraint position, but are configured to move from the restraint position to the release position for depositing the lower buttress assembly (<NUM>) on end effector (<NUM>) (see <FIG>). In the present example, left actuator sled (<NUM>) is distinct from right actuator sled (<NUM>) for reasons discussed below in greater detail. Also, upper and lower right actuator sleds (<NUM>) are structurally identical to each other, and upper and lower left actuator sleds (<NUM>) are structurally identical to each other. Thus, upper and lower actuator sleds (<NUM>, <NUM>) are interchangeable in this respect and any discussion contained herein directed to a pair of upper actuator sleds (<NUM>, <NUM>) is similarly applicable to a pair of lower actuator sleds (<NUM>, <NUM>).

Each actuator sled (<NUM>, <NUM>) includes a plurality of arms (55a, 55b, 55c) extending laterally inward to selectively and releasably secure buttress assemblies (<NUM>) to platform (<NUM>). In particular, <FIG> show arms (55a, 55b, 55c) positioned such that buttress assemblies (<NUM>) are interposed between the free ends of arms (<NUM>) and platform (<NUM>). Arms (55a, 55b, 55c) are movable laterally outwardly such that arms (55a, 55b, 55c) disengage buttress assemblies (<NUM>) as shown in <FIG>, thereby enabling buttress assemblies (<NUM>) to be removed from platform (<NUM>). In the present example, arms (55a, 55b, 55c) are configured to bear against buttress assemblies (<NUM>) in the restraint position, thereby pinching buttress assemblies (<NUM>) against platform (<NUM>). Other suitable ways in which arms (<NUM>) may engage buttress assemblies (<NUM>) will be apparent to those of ordinary skill in the art in view of the teachings herein.

Chassis (<NUM>) is configured to cooperate with upper and lower housings (<NUM>, <NUM>) to provide a mechanical ground for moving components of buttress applier cartridge (<NUM>) and provide structural support for components of buttress applier cartridge (<NUM>). Chassis (<NUM>) further includes integral gripping features (<NUM>) that are exposed on opposite sides of housing assembly (<NUM>). Gripping features (<NUM>) have a surface geometry configured to promote an operator's grip of buttress applier cartridge (<NUM>) during use of buttress applier cartridge (<NUM>). Various suitable configurations that may be used for gripping features (<NUM>) will be apparent to those of ordinary skill in the art in view of the teachings herein. Similarly, various surface treatments (e.g., elastomeric material, etc.) that may be applied to gripping features (<NUM>) will be apparent to those of ordinary skill in the art in view of the teachings herein.

With respect to <FIG>, platform (<NUM>) is connected to and supported by chassis (<NUM>) to secure platform (<NUM>) relative to upper and lower housing (<NUM>, <NUM>) (see <FIG>). In the present example, platform (<NUM>) is unitarily formed and molded to a rigid web portion (<NUM>) including a frame (<NUM>) and defining a plurality of holes (<NUM>, <NUM>, <NUM>) configured provide material overlap for mold securement. Holes (<NUM>, <NUM>, <NUM>) more particularly include an upper and a lower peripheral recess (<NUM>) to the centrally located frame (<NUM>). A central slot (<NUM>) extends through frame (<NUM>) as well as a plurality of through holes (<NUM>) spaced laterally about central slot (<NUM>). Frame (<NUM>) also extends laterally across central slot (<NUM>) at bridge portions (<NUM>) to provide additional structural rigidity to chassis (<NUM>) while providing platform (<NUM>) with sufficient clearance for resilient deformation as discussed below in greater detail. Thereby, recess (<NUM>), central slot (<NUM>), and through holes (<NUM>) receive a resilient, elastomeric material to form and secure the material as platform (<NUM>) to chassis (<NUM>). While the present platform (<NUM>) is molded to chassis (<NUM>), it will be appreciated that platform (<NUM>) may be alternatively secured to chassis (<NUM>), and the invention is not intended to be limited to the particular rigid web portion (<NUM>) and molding as discussed herein. Various suitable materials and structural configurations that may be used to form platform (<NUM>) will be apparent to those of ordinary skill in the art in view of the teachings herein.

Chassis (<NUM>) further includes a plurality of sled clearance holes (<NUM>) arranged in a pair of rows on opposing lateral sides of chassis (<NUM>). Left and right actuator sleds (<NUM>, <NUM>) (see <FIG>) connect together on opposing sides of chassis (<NUM>) through such sled clearance holes (<NUM>) to slide inwardly together in connected pairs. Additional details regarding connection and actuation of left and right actuator sleds (<NUM>, <NUM>) (see <FIG>) will be discussed below in greater detail. However, it will be appreciated that any such hole through chassis (<NUM>) to provide for fastening clearance of left and right actuator sleds (<NUM>, <NUM>) (see <FIG>) may be used, and the invention is not intended to be unnecessarily limited to sled clearance holes (<NUM>) as discussed herein.

<FIG> show one example of platform (<NUM>) in additional detail as including a pad (<NUM>) having a peripheral securement (<NUM>) laterally extending therefrom and an anchor securement (<NUM>) distally extending therefrom. Collectively, peripheral and anchor securements (<NUM>, <NUM>) are positioned in recesses (<NUM>) and extend into through holes (<NUM>) to secure pad (<NUM>) to chassis (<NUM>). In some versions, platform (<NUM>) is formed of a material that provides a high coefficient of friction, thereby reducing any tendency that buttress assemblies (<NUM>) might otherwise have to slide along corresponding surfaces of platform (<NUM>). For instance, platform (<NUM>) may comprise a resilient, elastomeric material, such as silicone, to be molded to be formed as both securements (<NUM>, <NUM>) and pad (<NUM>). One example silicone material is a <NUM> Durometer, Shore A silicone. To this end, pad (<NUM>) is formed with varying stiffness along its longitudinal length to simultaneously provide sufficient reactionary forces of at least the predetermined minimum force for adhesion while accommodating a parallel-camber orientation, an over-camber orientation, and an under-camber orientation of end effector (<NUM>) (see <FIG>) as discussed below in greater detail. As used herein, the term "parallel-camber orientation" refers to an upper jaw and a lower jaw of an end effector being functionally parallel to each other. The term "over-camber orientation" refers to an upper jaw of an end effector being over rotated relative a lower jaw of an end effector. The term "under-camber orientation" refers to an upper jaw being under rotated relative to a lower jaw of an end effector. Exemplary upper and lower jaws will be described in this context below in greater detail.

With respect to <FIG>, a resilient proximal end (<NUM>) pad (<NUM>) has a proximal end stiffness and a proximal transverse depth, whereas a resilient distal end (<NUM>) of pad (<NUM>) has a distal end stiffness and a distal transverse depth. In the present example, proximal end stiffness is generally greater than the distal end stiffness such that initial compression of distal end (<NUM>) requires less compressive force than compression of proximal end (<NUM>). Of course, further compression of distal end (<NUM>) relative to proximal end (<NUM>) may result in distal end stiffness increasing to or even exceeding proximal end stiffness so long as the lesser stiffness of distal end (<NUM>) is included therein for accommodating the over-cambered orientation of end effector (<NUM>) (see <FIG>).

In addition, distal transverse depth is greater than proximal transverse depth. Thereby, the greater distal transverse depth effectively props up buttress assembly (<NUM>) (see <FIG>) for improved engagement with end effector (<NUM>) (see FIG. 10A) in the under-camber orientation, but the decreased distal end stiffness allows for greater compression to accommodate end effector (<NUM>) (see FIG. 10A) in the over-camber orientation. Pad (<NUM>) of the present example is wedge-shaped having opposing ramp surfaces (<NUM>) continuously tapering together from the distal end (<NUM>) to the proximal end (<NUM>) for accommodating parallel-camber, over-camber, and under-camber orientations along the entire longitudinal length of pad (<NUM>). In some examples, depths and stiffnesses along pad (<NUM>) are configured to receive a full range of over-camber to under-camber orientations based on determined manufacturing tolerances of end effector (<NUM>) (see FIG.

Pad (<NUM>) shown in <FIG> is unitarily formed of a resilient material having a consistent stiffness throughout. Such longitudinally varying stiffness discussed above is thus generated by forming a plurality of reliefs, such as channels (<NUM>), in at least the distal end (<NUM>) to reduce the distal end stiffness relative to the proximal end stiffness. In the present example, channels (<NUM>), such as five channels (<NUM>) are equally spaced laterally apart from each other and longitudinally extend from distal end (<NUM>) to proximal end (<NUM>). Channels (<NUM>) further transversely extend to a base surface (<NUM>) common to securements (<NUM>, <NUM>) and proximal end (<NUM>) to define varying channel depths in the longitudinal direction along pad (<NUM>). More particularly, upper channels (<NUM>) extend transversely downward from upper ramp surface (<NUM>) to upper base surface (<NUM>), whereas lower channels (<NUM>) extend transversely upward from lower ramp surface (<NUM>) to lower base surface (<NUM>). In turn, a plurality of ribs (<NUM>) are defined between channels (<NUM>) and similarly extend from ramp surfaces (<NUM>) to base surfaces (<NUM>) to support buttress assemblies (<NUM>) (see <FIG>) and have varying stiffness from the proximal end (<NUM>) to the distal end (<NUM>) on each opposing side of pad (<NUM>).

<FIG> and <FIG> show restraint features, such as left and right actuator sleds (<NUM>, <NUM>) discussed briefly above for releasably securing buttress assemblies (<NUM>) to platform (<NUM>) in the restraint position. Each of left and right actuator sleds (<NUM>, <NUM>) has arms (55a, 55b, 55c) configured to accommodate varying transverse depths along the longitudinal length of pad (<NUM>). More particularly, arms (55a, 55b, 55c) include a distal arm (55a), an intermediate arm (55b), and a proximal arm (55c) spaced longitudinally apart from each other and extending laterally inward toward platform (<NUM>). Each distal arm (55a), intermediate arm (55b), and proximal arm (55c) of left or right actuator sled (<NUM>, <NUM>) transversely extends toward platform (<NUM>) such that each of distal arm (55a), intermediate arm (55b), and proximal arm (55c) is offset from the other arms (55a, 55b, 55c) in the transverse direction. Thereby, distal arm (55a), intermediate arm (55b), and proximal arm (55c) are transversely spaced from the ramp surface (<NUM>) to trace the contour of the ramp surface (<NUM>).

With respect to <FIG>, upper left actuator sled (<NUM>) has a longitudinally extending upper left sled body (<NUM>) with distal, intermediate, and proximal arms (55a, 55b, 55c) laterally extending inward toward the right. Each arm (55a, 55b, 55c) of left actuator sled (<NUM>) has a cam surface (<NUM>) configured to receive end effector (<NUM>) (see <FIG>) thereagainst to urge left actuator sled (<NUM>) toward the release position. In addition, a pair of outer dowel holes (<NUM>) open downward and are respectively positioned on distal and proximal end portions of upper left sled body (<NUM>). A pair of inner dowels (<NUM>) extend downward from left sled body (<NUM>) between outer dowel holes (<NUM>) and in longitudinal alignment with outer dowel holes (<NUM>). In order to arrest movement of upper left actuator sled (<NUM>) in the restraint and release positions, a distal cantilever catch (<NUM>) laterally extends to the left from the distal portion of upper left sled body (<NUM>), and a proximal cantilever catch (<NUM>) laterally extends to the left from the proximal portion of upper left sled body (<NUM>). Distal and proximal cantilever catches (<NUM>, <NUM>) are respectively portions of distal and proximal detent couplings (<NUM>, <NUM>) discussed below in greater detail.

With respect to <FIG>, upper right actuator sled (<NUM>) has a longitudinally extending upper right sled body (<NUM>) with distal, intermediate, and proximal arms (55a, 55b, 55c) laterally extending inward toward the left. Each arm (55a, 55b, 55c) of right actuator sled (<NUM>) has a cam surface (<NUM>) configured to receive end effector (<NUM>) (see <FIG>) thereagainst to urge left actuator sled (<NUM>) toward the release position. In addition, a pair of inner dowel holes (<NUM>) open downward and are positioned on upper right sled body (<NUM>). A pair of outer dowels (<NUM>) extend downward from right sled body (<NUM>) and are respectively positioned on distal and proximal end portion of upper right sled body (<NUM>) in longitudinal alignment with inner dowel holes (<NUM>). In order to arrest movement of upper right actuator sled (<NUM>) in the restraint and release positions, another distal cantilever catch (<NUM>) laterally extends to the right from the distal portion of upper right sled body (<NUM>), and another proximal cantilever catch (<NUM>) laterally extends to the right from the proximal portion of upper right sled body (<NUM>). Again, distal and proximal cantilever catches (<NUM>, <NUM>) are respectively portions of distal and proximal detent couplings (<NUM>, <NUM>) discussed below in greater detail.

<FIG> and <FIG> show upper right and left actuator sleds (<NUM>, <NUM>) as discussed above in detail as well as lower right and left actuator sleds (<NUM>, <NUM>). As briefly discussed above, the description of upper right and left actuator sleds (<NUM>, <NUM>) similarly applies to lower right and left actuator sleds (<NUM>, <NUM>) with like features having like numbers, but with reversed transverse directions (e.g. lower, upward, etc.). To this end, upper left actuator sled (<NUM>) and lower right actuator sled (<NUM>) connect together as outer dowels (<NUM>) snap into outer dowel holes (<NUM>) and inner dowels (<NUM>) snap into inner dowel holes (<NUM>) with chassis (<NUM>) positioned therebetween. Upper right actuator sled (<NUM>) and lower left actuator sled (<NUM>) similarly connect together as outer dowels (<NUM>) snap into outer dowel holes (<NUM>) and inner dowels (<NUM>) snap into inner dowel holes (<NUM>) with chassis (<NUM>) positioned therebetween. Each of inner and outer dowels (<NUM>, <NUM>) extend through sled clearance holes (<NUM>) to slidably connect left and right actuator sleds (<NUM>, <NUM>) to chassis (<NUM>).

<FIG> shows one example of a pair of distal arms (55a), a pair of intermediate arms (55b), and a pair of proximal arms (55c) respectively having platform (<NUM>) positioned therebetween and tracing opposing ramp surfaces (<NUM>). A central plane (<NUM>) is shown in <FIG> bisecting upper and lower portions of buttress applier cartridge (<NUM>) through a central core of platform (<NUM>). Distal arm (55a) has a distal retention surface (112a) transversely offset from central plane (<NUM>) a relatively greater distance, intermediate arm (55b) has an intermediate retention surface (112b) transversely offset from central plane (<NUM>) a relatively intermediate distance, and proximal arm (55c) has a proximal retention surface (112c) transversely offset from central plane (<NUM>) a relatively lesser distance. Thereby, greater, intermediate, and lesser distances of distal, intermediate, and proximal retention surfaces (112a, 112b, 112c) trace ramp surfaces (<NUM>) tapering from distal end (<NUM>) of pad (<NUM>) to proximal end (<NUM>) of pad (<NUM>). Thus, distal, intermediate, and proximal retention surfaces (112a, 112b, 112c) are offset in the transverse direction from each other and from central plane (<NUM>). In the present example, each of distal arm (55a), intermediate arm (55b), and proximal arm (55c) are transversely spaced from the ramp surface (<NUM>) an equal transverse dimension such that arms (55a, 55b, 55c) equally trace ramp surfaces (<NUM>) tapering from distal end (<NUM>) of pad (<NUM>) to proximal end (<NUM>) of pad (<NUM>).

As shown in <FIG>, left and right actuator sleds (<NUM>, <NUM>) are respectively urged outward from the restraint position to the release position away from platform to disengage arms (55a, 55b, 55c) from buttress assemblies (<NUM>) (see <FIG>) on platform (<NUM>) as discussed herein. More particularly, distal and proximal detent couplings (<NUM>, <NUM>) releasably connected left and right actuator sleds (<NUM>, <NUM>) to chassis (<NUM>) to arrest movement of left and right actuator sleds (<NUM>, <NUM>) in the restraint position and the release position. Distal and proximal detent couplings (<NUM>, <NUM>) include distal and proximal cantilever catches (<NUM>, <NUM>) extending from each of left and right actuator sleds (<NUM>, <NUM>) as discussed briefly above. In addition, distal and proximal detent couplings (<NUM>, <NUM>) respectively further include distal and proximal ground cams (<NUM>, <NUM>) extending from chassis (<NUM>) in respective engagement with distal and proximal cantilever catches (<NUM>, <NUM>).

In the restraint position shown in <FIG>, each distal cantilever catch (<NUM>) is respectively engaged with each distal ground cam (<NUM>), and each proximal cantilever catch (<NUM>) is respectively engaged with each proximal ground cam (<NUM>) to urge left and right actuator sleds (<NUM>, <NUM>) inward toward the restraint position. Directing left and right actuator sleds (<NUM>, <NUM>) outward from the restraint position toward the release position as shown in <FIG> resiliently deflects distal and proximal cantilever catches (<NUM>, <NUM>) as distal and proximal cantilever catches (<NUM>, <NUM>) follow distal and proximal ground cams (<NUM>, <NUM>). As distal and proximal cantilever catches (<NUM>, <NUM>) pass around distal and proximal ground cams (<NUM>, <NUM>), distal and proximal cantilever catches (<NUM>, <NUM>) reach a tipping point where distal and proximal cantilever catches (<NUM>, <NUM>) urge left and right actuator sleds (<NUM>, <NUM>) to the release position shown in <FIG>. In the release position, each distal cantilever catch (<NUM>) is respectively engaged with each distal ground cam (<NUM>), and each proximal cantilever catch (<NUM>) is respectively engaged with each proximal ground cam (<NUM>) to urge left and right actuator sleds (<NUM>, <NUM>) outward toward the release position. Thereby, distal and proximal detent couplings (<NUM>, <NUM>) effectively hold left and right actuator sleds (<NUM>, <NUM>) in the release position to inhibit arms (55a, 55b, 55c) from inadvertently returning inward and catching buttress assembly (<NUM>) (see <FIG>) upon removal of end effector (<NUM>) (see <FIG>) as discussed below in greater detail.

As noted above and discussed below in greater detail with respect to <FIG>, upper and lower buttress assemblies (<NUM>) include upper and lower adhesive layers (<NUM>) (or other form of adhesive material) to adhere respective buttresses (<NUM>) to an underside (<NUM>) of anvil (<NUM>) and deck (<NUM>) of staple cartridge (<NUM>). Such adhesive may provide proper positioning of buttress (<NUM>) before and during actuation of end effector (<NUM>); then allow buttress (<NUM>) to separate from end effector (<NUM>) after end effector (<NUM>) has been actuated, without causing damage to buttress (<NUM>) that is substantial enough to compromise the proper subsequent functioning of buttress (<NUM>).

To use buttress applier cartridge (<NUM>) to load end effector (<NUM>), the operator would first position buttress applier cartridge (<NUM>) and end effector (<NUM>) such that end effector (<NUM>) is aligned with open end (<NUM>) of buttress applier cartridge (<NUM>) as shown in <FIG>. The operator would then advance end effector (<NUM>) distally (and/or retract buttress applier cartridge (<NUM>) proximally) to position platform (<NUM>) and buttress assemblies (<NUM>) between anvil (<NUM>) and staple cartridge (<NUM>). In order to load buttress assemblies (<NUM>) on end effector (<NUM>), the operator simply closes end effector (<NUM>) by pivoting anvil (<NUM>) toward staple cartridge (<NUM>) to reach the state shown in <FIG>.

As shown, closure of end effector (<NUM>) to the parallel-camber orientation results in anvil (<NUM>) and staple cartridge (<NUM>) bearing against actuator sleds (<NUM>), thereby urging arms (<NUM>) to unlock buttress assemblies (<NUM>) from buttress applier cartridge (<NUM>). Adhesive layers (<NUM>) of upper and lower buttress assemblies (<NUM>) are sufficiently compressed against anvil (<NUM>) and deck (<NUM>) to retain upper and lower buttress assemblies (<NUM>) to end effector (<NUM>) for stapling tissue. Pad (<NUM>) accommodates the parallel-camber orientation shown in <FIG> by providing reaction forces of at least the predetermined minimum force for adhesion along the longitudinal length of buttress assemblies (<NUM>). Upon depositing buttress assemblies (<NUM>) onto anvil (<NUM>) and staple cartridge (<NUM>), the operator removes buttress applier cartridge (<NUM>) from end effector (<NUM>) as shown in <FIG>.

To this end, <FIG> show a sequence where end effector (<NUM>) loaded with buttress assemblies (<NUM>) is actuated to drive a plurality of staples (<NUM>) through two apposed layers of tissue (T<NUM>, T<NUM>), with buttress assemblies (<NUM>) being secured to the same layers of tissue (T<NUM>, T<NUM>) by staples (<NUM>). In particular, <FIG> shows layers of tissue (T<NUM>, T<NUM>) positioned between anvil (<NUM>) and staple cartridge (<NUM>), with anvil (<NUM>) in the open position. Upper buttress assembly (<NUM>) is adhered to the underside (<NUM>) of anvil (<NUM>) via adhesive layer (<NUM>); while lower buttress assembly (<NUM>) is adhered to deck (<NUM>) of staple cartridge (<NUM>) via adhesive layer (<NUM>). Layers of tissue (T<NUM>, T<NUM>) are thus interposed between upper and lower buttress assemblies (<NUM>). Next, a trigger (not shown) is pivoted to drive anvil (<NUM>) to the closed position as shown in <FIG>. At this stage, layers of tissue (T<NUM>, T<NUM>) are compressed between anvil (<NUM>) and staple cartridge (<NUM>), with upper and lower buttress assemblies (<NUM>) engaging opposite surfaces of tissue layers (T<NUM>, T<NUM>). End effector (<NUM>) is then actuated as described above, driving staple (<NUM>) through upper and lower buttress assemblies (<NUM>) and layers of tissue (T<NUM>, T<NUM>). As shown in <FIG>, a crown (<NUM>) of driven staple (<NUM>) captures and retains lower buttress assembly (<NUM>) against layer of tissue (T<NUM>). Deformed legs (<NUM>) of staple (<NUM>) capture and retain upper buttress assembly (<NUM>) against layer of tissue (Ti).

It should be understood that a series of staples (<NUM>) will similarly capture and retain upper and lower buttress assemblies (<NUM>) against layers of tissue (T<NUM>, T<NUM>), thereby securing upper and lower buttress assemblies (<NUM>) to tissue (T<NUM>, T<NUM>). In one example, knife (not shown) cuts through a centerline of buttress assemblies (<NUM>), separating buttress assemblies (<NUM>) into a corresponding pair of sections, such that each section remains secured to a respective severed region of tissue (T<NUM>, T<NUM>) as shown in <FIG>.

With respect to <FIG>, as end effector (<NUM>) (see <FIG>) is pulled away from tissue (T<NUM>, T<NUM>) after deploying staples (<NUM>) and upper and lower buttress assemblies (<NUM>), upper and lower buttress assemblies (<NUM>) disengage end effector (<NUM>), such that upper and lower buttress assemblies (<NUM>) remain secured to tissue (T<NUM>, T<NUM>) with staples (<NUM>). Buttressed tissue (T<NUM>, T<NUM>) thus provides structural reinforcement to the lines of staples (<NUM>). In addition to the foregoing, it should also be understood that any of the various buttress assemblies described herein may be further constructed and operable in accordance with at least some of the teachings of <CIT>.

<FIG> show pad (<NUM>) accommodating alternative camber orientations of end effector (<NUM>), such as the over-camber orientation and the under-camber orientation. With respect to <FIG>, closure of end effector (<NUM>) to the over-camber orientation results in anvil (<NUM>) and staple cartridge (<NUM>) unlocking buttress assemblies (<NUM>) from buttress applier cartridge (<NUM>) as discussed above. Adhesive layers (<NUM>) of upper and lower buttress assemblies (<NUM>) are sufficiently compressed against anvil (<NUM>) and deck (<NUM>) to retain upper and lower buttress assemblies (<NUM>) to end effector (<NUM>) for stapling tissue. Pad (<NUM>) accommodates the over-camber orientation by providing reaction forces of at least the predetermined minimum force for adhesion along the longitudinal length of buttress assemblies (<NUM>).

Similarly, <FIG> shows closure of end effector (<NUM>) to the under-camber orientation resulting in anvil (<NUM>) and staple cartridge (<NUM>) unlocking buttress assemblies (<NUM>) from buttress applier cartridge (<NUM>) as discussed above. Adhesive layers (<NUM>) of upper and lower buttress assemblies (<NUM>) are sufficiently compressed against anvil (<NUM>) and deck (<NUM>) to retain upper and lower buttress assemblies (<NUM>) to end effector (<NUM>) for stapling tissue. Pad (<NUM>) accommodates the under-camber orientation by providing reaction forces of at least the predetermined minimum force for adhesion along the longitudinal length of buttress assemblies (<NUM>).

In addition to the foregoing, it should also be understood that any of the various buttress assemblies described herein may be further constructed and operable in accordance with at least some of the teachings of <CIT>; <CIT>; <CIT>; and <CIT>. Furthermore, in addition to the methods described herein, any of the various buttress assemblies described herein may be applied to end effector (<NUM>) in accordance with at least some of the teachings of <CIT>; and/or <CIT>. Various suitable ways in which the teachings herein may be combined with various teachings of the above-cited references will be apparent to those of ordinary skill in the art.

Claim 1:
A buttress applier cartridge assembly (<NUM>), comprising:
(a) a first buttress assembly (<NUM>), including:
(i) a first buttress (<NUM>) configured to be received against tissue and support a staple formed therein, and
(ii) a first adhesive layer (<NUM>) on the first buttress configured to releasably adhere the first buttress against a first portion of an end effector (<NUM>) of a surgical stapler (<NUM>) upon engaging the first adhesive layer against the end effector with at least a predetermined minimum force; and
(b) a buttress applier cartridge (<NUM>), including:
(i) a housing (<NUM>) defining a first gap (<NUM>) extending in a longitudinal direction therealong such that the first gap is configured to receive the first portion of the end effector, and
(ii) a platform (<NUM>) extending longitudinally from a proximal platform portion (<NUM>) to a distal platform portion (<NUM>) and operatively connected to the housing, wherein the platform is exposed in a transverse direction adjacent to the first gap and the proximal and distal platform portions respectively have a proximal stiffness and a different, distal stiffness in the transverse direction,
wherein the proximal and distal platform portions support the first buttress assembly thereon and are configured to deform with the proximal and distal stiffnesses thereby providing reactionary forces of at least the predetermined minimum force while receiving the end effector for accommodating various camber orientations of the end effector, and
wherein the platform includes a platform pad (<NUM>), and
characterised in that the platform further includes a plurality of reliefs in at least one of the proximal and distal platform portions, wherein the plurality of reliefs are configured to generate the differing proximal and distal stiffnesses in the platform.