BUTTRESS FIXATION FOR A CIRCULAR STAPLER

[0001] This application is a continuation of U.S. patent application Ser. No. 13/648,703, filed Oct. 10, 2012, the entire contents of which are incorporated herein by reference.

[0002] The present application relates to surgical stapling apparatus and, in particular, surgical stapling apparatus having a buttress releasably fixed thereto.

[0003] Attaching surgical buttresses or staple line reinforcement materials to surgical staplers is known. Trumbull et al., U.S. Pat. No. 5,263,629, the disclosure of which is hereby incorporated by reference herein in its entirety, discloses an absorbent and bioabsorbable pledget material attached to a surgical stapler. Buttresses used in conjunction with a tubular sleeve have been proposed. For example, U.S. Pat. No. 5,503,638 to Cooper et al., the entire disclosure of which is hereby incorporated by reference herein, proposes a tubular sleeve dimensioned to fit over and closely surround the jaws of a stapler. The sleeve can be made from non-woven polyethylene attached to a strip of material made from animal tissue.

[0004] McKean et al., U.S. Pat. No. 5,542,594, the entire disclosure of which is hereby incorporated by reference herein, discloses a stapling apparatus having biocompatible fabric releasably attached thereto. The fabric can be tubular in configuration for attachment to the stapling apparatus, or can be attached using pins.

[0005] Tarinelli et al., International Publication No. WO 08/109125, the entire disclosure of which is hereby incorporated by reference herein, discloses an anchor, or a suture material, for attaching a buttress, which is released when the anchor, or suture, is cut by a knife.

[0006] Mooradian et al., WO 03/082126, the entire disclosure of which is hereby incorporated by reference herein, discloses a circular stapling apparatus having a buttress material positioned on the staple cartridge and/or anvil. The buttress material may be preformed so as to have a raised central region so that it can be positioned on the staple cartridge and/or anvil.

[0007] There is a need for reliable methods of removably attaching a staple line reinforcement material or buttress material onto a circular stapling apparatus, or other stapling apparatus, so that the material does not interfere with the operation of the apparatus, remains on the apparatus until after the staples are fired, and is convenient and easy to install and use.

[0008] In an aspect of the present disclosure, a circular stapling apparatus has an anvil assembly with an anvil member and a shaft, and a tubular body portion. The shaft of the anvil assembly is connectable to the tubular body portion so that the anvil assembly is movable toward and away from the tubular body portion. A buttress material is removably attached to the anvil assembly, staple cartridge, or both, by at least one anchor, at least one of the anvil assembly and staple cartridge have a notch shaped for retaining the anchor thereto.

[0009] The apparatus has a pusher with a fingers for driving the staples. At least one of the fingers includes a protrusion. At least one of the anvil assembly and staple cartridge has a notch shaped for retaining the anchor, the pusher being movable to move the protrusion into engagement with the anchor in the notch.

[0010] The anchor may be a length of suture. The apparatus may further comprise adhesive. The apparatus may further comprise a fastener holding the anchor and being positioned adjacent the notch. In certain embodiments, the notch pinches the anchor. The notch can be defined in a tissue contacting surface of the at least one of the anvil assembly and staple cartridge. The notch may communicate with a staple receiving recess of the staple cartridge. The notch may communicates with a staple forming recess of the anvil member.

[0011] In certain embodiments, the notch has a first portion and a second portion, the first portion being smaller in dimension than the diameter of the anchor, and the second portion being bigger than the first portion.

[0012] The buttress material can define features selected from the group consisting of slits and perforations. The buttress material can define slits that extend from an outer edge thereof. The protrusion may cut the anchor.

[0022] Persons having skill in the art will understand the present invention from reading the following description in conjunction with the accompanying drawings. Reference characters indicate the same or similar elements throughout the drawings. As is customary, the term “distal” refers to a location farther from the user of the instrument and the term “proximal” refers to a location that is closer to the user of the instrument.

[0023] A circular stapling instrument or apparatus (also referred to herein as a stapler) 10 is shown in FIGS. 1A-1B and has a handle portion 12, a tubular body portion 14, and an anvil assembly 20. The anvil assembly 20 is at the distal end of the instrument 10, and is movable toward and away from the tubular body portion 14. The handle portion 12 has at least one movable handle 33 for actuating the firing of staples 50 and the cutting of tissue 1, 2. A knob 35 is at the proximal end of the handle portion 12 and can be turned to move the anvil assembly 20 toward the tubular body portion 14 or away from the tubular body portion 14. A buttress 74 is shown generally disposed around the shaft 23.

[0024] Although a circular stapling apparatus is described in detail herein, in any of the embodiments disclosed herein, the stapling apparatus may be a linear endoscopic stapler, a linear stapler for open surgery, a transverse surgical stapler, or other surgical device. Circular staplers are disclosed in U.S. Pat. No. 5,915,616, the disclosure of which is hereby incorporated by reference in its entirety. Endoscopic staplers are disclosed in U.S. Pat. Nos. 6,330,965 and 6,241,139, the disclosures of which are hereby incorporated by reference in their entirety. Transverse surgical staplers are disclosed in U.S. Pat. No. 5,964,394, the disclosure of which is hereby incorporated by reference in its entirety. U.S. Pat. No. 7,334,717, the disclosure of which is hereby incorporated by reference in its entirety, discloses a stapler intended for open surgical procedures.

[0025] The tubular body portion 14 can be flexible, straight or curved, or otherwise configured for the surgical procedure. The distal end of the tubular body portion 14 has a staple cartridge 32 disposed therein. The staple cartridge 32 has a circular array of staple retaining or receiving slots 52 defined in a tissue contacting surface 51 of the staple cartridge 32. The anvil assembly 20 has an anvil member 21 with a circular array of staple forming recesses that correspond to the staple retaining or receiving slots 52. The anvil assembly 20 also has a shaft 23 that connects with a rod 15 in the tubular body portion 14.

[0026] A staple pusher 64 is disposed in the staple cartridge 32 and has a plurality of fingers or pushers 65 that are aligned with the staple receiving slots 52. The staple pusher 64 is a conical member that is disposed in the staple cartridge 32. The staple pusher 64 is movable in the distal direction to drive the staples 50 out of the staple cartridge 32 and toward the staple forming recesses in the anvil member 21. There are three circular rows of staples that are driven into tissue, as shown in FIG. 2. A knife 30 has a cylindrical shape and is disposed radially inwardly of the pushers 65. The knife 30 is mounted to a surface of the staple pusher 64 so that after the staples 50 are driven through tissue 1, 2 and into the staple forming recesses, the tissue radially interior to the circular rows of staples is cut. The staple cartridge 32 can be a removable and replaceable assembly so that the rest of the circular stapling apparatus 10 can be re-sterilized and reused, or the circular stapling apparatus 10 can be reused on the same patient without re-sterilization.

[0027] The rod 15 inside the tubular body portion 14 extends proximally through the apparatus 10 to the knob 35. The distal end of the knob 35 is attached to a member that has a helical groove defined on a surface thereof. A pin attached to a proximal end of the rod 15 is disposed in the groove so that, as the knob 35 is rotated, the pin travels in the groove, moving the rod 15 in a distal or proximal direction. The anvil shaft 23, which is attached to the rod 15, is also moved, moving the anvil assembly 20 toward or away from the tubular body portion 14. When the knob 35 is rotated in a first direction, the anvil assembly 20 is moved away from the tubular body portion 14, allowing tissue to be placed between the anvil assembly 20 and the tissue contacting surface 51 of the staple cartridge 32. When the knob 35 is rotated in a second direction, the anvil assembly 20 is moved toward the tubular body portion 14, allowing the tissue to be clamped between the staple cartridge 32 and anvil assembly 20. Other means of moving the anvil assembly with respect to the tubular body portion are contemplated. It is also contemplated, in any of the embodiments disclosed herein, that the instrument 10 can be connected to a motorized assembly. For example, a motorized assembly can be provided in the handle portion 12, and power can be supplied from external sources, or from a battery provided in the handle portion 12.

[0028] The pivotable handle or handles 33 can be connected to a tubular member or pair of bands that are attached to the staple pusher 64 by, for example, linkages or the like. In this way, when the handle or handles 33 are depressed 33, the tubular member or bands are advanced, advancing the staple pusher 64, driving the staples 50 through tissue 1, 2 and against the anvil member 21, and advancing the knife 30 to cut tissue radially inward of the rows of surgical staples 50.

[0029] As shown in FIGS. 2A and 2B, a buttress fixation system 70 is provided on the staple cartridge 32. The staple cartridge 32 has a plurality of staple receiving slots 52 defined in a tissue contacting surface 51 therein. Only a portion of the staple receiving slots 52 are shown in FIG. 2A, but it is understood that the rows of staple receiving slots 52 extend all the way around the circular face of the staple cartridge 32. The staple receiving slots 52 have an inner row 53, middle row 54, and an outer row 55. The middle row 54 of staple receiving slots 52 includes at least one notch 56 extending outwardly away from the rod 15 of the apparatus. This at least one notch 56 receives an anchor 72, which is a strap, cable, wire, thread, strand, or the like, which can be for example, a length of suture 72. The notch 56 is configured to have a shape that pinches the length of suture 72. For example, the notch 56 will have a first portion 56a with a first dimension, and a second portion 56b with a second dimension. The first dimension is smaller than the diameter, or cross-sectional dimension, of the length of suture 72, so that the length of suture 72 is retained in the notch 56. The second dimension is bigger than the first dimension, allowing the length of suture 72 to move out of the notch 56. In any of the embodiments disclosed herein, the notch 56 can have a shape like the number 8, the shape of the letter V, or any shape for retaining and releasing the anchor, or suture.

[0030] The anchor 72, which can be a strap, cable, wire, thread, strand, suture, or the like, is desirably a bioabsorbable suture, which can be made from polyglycolic acid, glycolide trimethylene carbonate, polylactic acid, or any of the bioabsorbable materials from which sutures, buttress materials, and other medical implants, can be made. Animal derived materials, which are known in the art, are also contemplated for the buttress and/or anchor. In any of the embodiments disclosed herein, the suture can be a material that is not bioabsorbable. In certain embodiments, the anchor 72 is attached to the stapler 10 and removed with the stapler 10 after the staples 50 have been fired. In certain embodiments, the anchor 72 is bioabsorbable and is attached to the buttress 74, or is formed as part of the buttress 74, and is left in the body of the patient. Alternatively, the surgeon can trim the anchor or anchors 72 during surgery.

[0031] The length of suture 72 can be attached to the buttress 74 by welding, or using an adhesive, or by heat pressing, or any known method. Alternatively, the length of suture 72 can be integrally formed with the buttress 74, as an extension thereof. For example, the buttress 74 can be formed as a circular disc, as shown in FIG. 3, and can have straps that extend from the outer edge 76 thereof. The straps can separate from the buttress 74 at perforations, or by virtue of the bioabsorbability of the material. For example, the straps can be made much thinner than the buttress 74. In another example, the straps or length of suture 72 can be trimmed by the surgeon after the staples 50 are fired and the stapling instrument 10 is removed from the site. The anchor 72 or anchors 72 can be one or more lengths of suture material. That is, the anchor 72 can be a single piece of suture, portions of which extending into the notch or notches 56 to retain the buttress 74. In any of the embodiments disclosed herein, the anchor 72 comprises a plurality or pieces of suture material that extend into corresponding notches 56.

[0032] In any of the embodiments disclosed herein, a fastener can be attached to the anchor 72, the surgical instrument 10 or both, to help retain the anchor 72 and the buttress 74 on the instrument 10. For example, the fastener can be an aglet or crush ring or clip attached to the anchor 72 at a location adjacent the notch 56.

[0033] The buttress fixation system 70 allows the buttress 74 to be released from the stapler 10 so that the stapler 10 can be removed from the site. The staple pusher 64 has a plurality of pushers or fingers 65, each of which extend into the staple receiving slots 52 to eject the staples 50. The fingers 65 have a shape that corresponds to the shape of the staple receiving slot 52. The fingers 65 that are disposed in the staple receiving slot or slots 52 that has the notch 56 have a corresponding protrusion or extension 67 that is disposed in the notch 56. As the staple pusher 64 is advanced, the fingers 65 advance, and the finger or fingers 65 that has the extension 67 will push the length of suture 72, strap, or the like, from the notch 56.

[0034] In any of the embodiments disclosed herein, the buttress itself can be made from a variety of biologically compatible materials, and can be made of the same material as the anchor. In certain preferred embodiments, the buttress material is a bio-absorbable material such as polyglycolic acid, glycolide trimethylene carbonate copolymer, polylactic acid, glycolide dioxanone and trimethylene carbonate copolymer, blends and copolymers. or any of the bio-absorbable materials used to make sutures, buttresses, and other medical implants. Non-absorbable materials can be used such as polypropylene or polyester. The buttress can be made from animal derived materials, which are known in the art. For example, the buttress material can be made from porcine or bovine tissue, such as porcine dermal collagen, collagen from bovine pericardium, or other materials. The buttress can be made by extrusion, felting, knitting or braiding, molding, non-woven techniques such as melt blown or spun bonding methods, or other methods. The buttress can be porous or non-porous. The buttress can be a foam or mesh. The buttress can have layers of different materials or be some other form of composite material. The buttress material can be made as described in U.S. patent application Ser. No. 13/293,215, filed on Nov. 10, 2011, now U.S. Patent Publication No. 2013-0123816, the entire disclosure of which is hereby incorporated by reference herein.

[0035] In any of the embodiments disclosed herein, the buttress 74 has a shape that discourages buckling or wrinkling of the buttress 74. For example, the buttress 74 shown in FIG. 3 has slits 75 extending from the outer edge 76 thereof. Other slits or openings in the buttress 74 may be provided. The buttress 74 has a hole in its middle for allowing the shaft of the stapler 10 to pass through.

[0036] In a further embodiment shown in FIG. 4, the circular stapling instrument 10 has two rows of staple receiving slots 152. The staple cartridge 132 has a tissue contacting surface 151 that defines an inner row 153 and an outer row 155 of staple receiving slots 152. Although only seven staple receiving slots 152 are shown in FIG. 4, it is understood that the slots 152 extend all the way around the tissue contacting surface 151 of the stapler 10. At least one of the staple receiving slots 152 in the inner row 153 has a notch 156 for the receipt of an anchor, length of suture, strap, wire etc 72, as described above in connection with FIGS. 2A and 3. The notch 156 has a first portion 156a and second portion 156b, as described above in connection with FIG. 2A. This buttress fixation system 170 allows the buttress 74 to be released from the stapler 10 so that the stapler 10 can be removed from the site. The stapler 10 is otherwise arranged as discussed above in connection with FIGS. 1 through 3. The staple pusher, such as staple pusher 64, is a conical member that is advanceable to eject the staples 50 from the slots 152, and has a plurality of pushers or fingers 65, each of which extend into the staple receiving slots 152. The fingers 65 have a shape that corresponds to the shape of the staple receiving slot 152. The fingers 65 that are disposed in the staple receiving slot or slots 152 that has the notch 156 have a corresponding extension 67 that is disposed in the notch 156. As the staple pusher 64 is advanced, the fingers 65 advance, and the finger or fingers 65 that has the extension 67 will push the length of suture, strap, or the like 72, from the notch 156. The buttress 74 may be as shown in FIG. 3, or it may be any generally circular buttress, formed from any of the materials described above. The anchor 72 is disposed in the notch 156 to retain the buttress 74 on the stapler 10, and can be attached to the buttress 74, or the stapler 10, as discussed above in connection with FIG. 3.

[0037] FIGS. 2A and 4 show the tissue contacting surface 51 or 151, and only one section of staple receiving slots 52 or 152. In certain embodiments, the buttress fixation system 70 or 170 has twelve staple receiving slots 52 or 152 distributed along the tissue contacting surface 51 or 151 and have the notch 56 or 156. More or fewer such notches 56 or 156 can be provided to securely attach the buttress 74 to the stapling instrument 10.

[0038] One of the fingers 65 of the staple pusher 64 is shown in FIG. 5, and includes the protrusion 67 for pushing the anchor 72 out of the notch 156. In any of the embodiments disclosed herein, the stapler 10 includes one or more staple pushers 64 for ejecting the staples 50 from the staple receiving slots 52, 152 and has a finger 65 that correspond to each of the slots 52, 152. The fingers 65 that correspond to the slots 52, 152 that have the notch 56, 156 for retaining the anchor 72 have protrusions 67 for pushing the anchor 72 out of the slot 52, 152.

[0039] As shown in FIG. 6, the buttress fixation system 70, 170 may be as described above in connection with FIGS. 1 through 5, with anchors 72 for retaining the buttress 274. The buttress 274 itself includes tabs 278 at the outer edge 276 of the buttress 274, which can be formed by providing slits 275 extending from the outer edge of the buttress 274, or by forming tabs 278 that extend outwardly from the outer edge 276. Tabs 278 may also be formed so as to extend from the lower surface of the buttress 274, adjacent an inner row or outer row of slots. The tabs 278 are arranged to extend into at least some of the staple receiving slots, such as slots 152 or 52 of FIGS. 2 and 4, and an anchor 72 extends into the notch associated with at least some of the slots, such as notches 156 or 56. In this way, the anchor 72 frictionally retains the buttress 274 onto the stapler 10, by engaging the tab 278 of the buttress 274. In any of the embodiments disclosed herein, the buttress fixation system 70, 170 includes a buttress 274 with tabs 278, anchors 72, or both, for releasably retaining the buttress 274.

[0040] In any of the embodiments disclosed herein, the tissue contacting surface of the staple cartridge and/or the tissue contacting surface of the anvil member, has a stepped or tapered cross-sectional shape. Desirably, one or more rows of staple receiving slots 52 are defined in a surface that has a different height than the surface in which one or more other rows of staple receiving slots are defined. In addition, in any of the embodiments disclosed herein, the size of the staples in certain of the staple receiving slots may be different than the size of the staples in other of the staple receiving slots. For example, the inner row of staples can be smaller in size (such as leg length) than the outer row of staples (which has a greater leg length) or, if there are three rows of staple receiving slots, the inner row of staples cam be smaller than the middle row of staples and the outer row of staples.

[0041] In any of the embodiments disclosed herein, the staple receiving slots can have a curved or angled shape. This allows the staple receiving slots to be positioned more closely to one another in the staple cartridge and/or anvil. The staple forming recesses on the anvil member can have a corresponding shape so that the recesses can be more closely positioned with respect to one another on the anvil member. The staples desirably have a corresponding shape.

[0042] Although circular stapling instruments are described above, the stapling instrument could have rows of staples, staple forming recesses, and staple receiving slots that do not define a full circle, but rather a semi-circular, oval, or semi-oval shape. The stapling instrument could have rows of staples, staple forming recesses, and staple receiving slots that form some other shape, such as various polygonal shapes, or partially polygonal shapes. While the present invention has been described in several embodiments, it is not the intention to restrict or in any way limit the scope of the appended claims. Additional advantages and modifications may readily appear to those skilled in the art.