DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0037] Preferred embodiments of the presently disclosed absorbable surgical fastener apparatus and method of applying same will now be described in detail with reference to the drawing figures wherein like reference numerals identify similar or identical structural elements.

[0038] The presently disclosed absorbable surgical fastener apparatus and method is shown and described herein in connection with open and laparoscopic inguinal, femoral and ventral hernia repairs. Although not described in detail herein, the absorbable fastener can also be applied to other procedures which require that objects be attached to body tissue.

[0039] Referring initially to FIGS. 1 and 2 , an absorbable surgical fastener apparatus for connecting objects to body tissue, such as absorbable fastener 10 includes dual fastener anchors 12 and 14 secured to one another by a suture tether 16 extending therebetween. Each anchor 12 and 14 has a substantially cylindrical body portion 18 having a conically tapered distal end 20 and a substantially planar proximal end surface 22 . Anchors 12 and 14 are preferably provided with conically shaped distal ends 20 for easier penetration of anchors 12 and 14 into hard tissues, such as, for example, Cooper's ligament. While a generally conical distal end has been disclosed, it is envisioned that other shaped ends (e.g., pyramid, and the like) can be provided. Each anchor 12 and 14 is provided with a pair of opposed flattened side surfaces 22 extending longitudinally along the length thereof.

[0040] Anchors 12 and 14 are provided with barbs 12 a , 12 b , 12 c , and 14 a , 14 b , 14 c respectively to inhibit fastener pull-out occurrences in either hard or soft tissue. Each barb is semi-circular having a planar proximal surface 24 which is orthogonal to a central longitudinal axis “A” of each anchor 12 and 14 , and a tapered lower surface 26 . Preferably, barbs 12 a - 12 c and 14 a - 14 c share a common central axis “B”, however, it is envisioned that each respective barb can have a different center as compared to other barbs on the anchor. Preferably, central axis “B” is spaced a distance “X” from longitudinal axis “A”. In this manner, the center of barbs 12 a - 12 c and 14 a - 14 c can be positioned to reveal a greater amount of planar proximal surface 24 in order to provide an anchor with predetermined anchoring and securing characteristics for body tissue without compromising the strength of body portion 18 of each anchor 12 and 14 . For example, if greater retaining strength is desired, distance “X” between central axis “B” and longitudinal axis “A” is increased thereby forming a bard with a larger planar proximal surface 24 . In the case of securing a fastener to soft tissue, as is the case in hernia repair, a fastener having a larger projecting barb is desired in order to better anchor the fastener into the soft tissue of the patient.

[0041] While each barb 12 a - 12 c and 14 a - 14 c is orthogonal to longitudinal axis “A” of each anchor 12 and 14 respectively, it is envisioned that each barb can be angled relative to longitudinal axis “A” such that barbs 12 a , 12 b and 12 c form a partial thread around body portion 18 of each anchor 12 and 14 . In this manner, as each anchor 12 and 14 is pressed into body tissue, each anchor 12 and 14 will rotate into the body tissue.

[0042] Although the embodiment of FIGS. 1 and 2 illustrate barbs formed partially around the circumference of anchors 12 and 14 , multiple barb configurations can be utilized and are within the scope of the present disclosure. For example, in addition to the illustrated configuration, single barb, circumferential barb (i.e., barbs encircling the entire anchor), sharp barbs, dull barbs, multiple barbs, and various geometrically shaped barbs may be utilized.

[0043] While a planar proximal end 20 has been shown, it is envisioned that each anchor 12 and 14 can be provided with a notch or detent (not shown) formed in the proximal end thereof. In this manner, when a series of absorbable fasteners 10 are joined together, the tapered distal ends 18 are received in the detents to thereby maintain the absorbable fasteners 10 and anchors 12 and 14 longitudinally aligned with one another.

[0044] Absorbable fasteners 10 are preferably made of medical grade absorbable materials, for example, Polyglycolic Acid (PGA) and Polylactic Acid (PLA). A critical feature of the presently disclosed absorbable fastener is that the absorbable fastener provide sufficient strength to retain a mesh material in place for a desired period of time. For example, in the case of applying a hernia repair mesh material, it is recommended that absorbable fasteners 10 remain in place retaining the mesh material for approximately 2-3 weeks and be absorbed into the body tissue anytime after that.

[0045] It is preferred that absorbable fasteners 10 are approximately 3 mm long, from the tip of distal end 18 to proximal end 20 , by approximately 1.5 mm in diameter. Other suitably configured and dimensioned fasteners may also be utilized depending on the particular application. It is also preferred that absorbable fasteners 10 are configured and dimensioned to avoid penetrating too far into the tissue. An example of a similar fastener structure and an instrument for applying such fasteners are disclosed in U.S. Pat. No. 5,997,552 (hereinafter “the '552 patent”), issued to Person et al. and entitled Meniscle Fastener Applying Device, the entire contents of which are hereby incorporated by reference. Unlike the fastener in the '552 patent, the barbs of fastener 10 according to the present disclosure have a center “B” which is spaced a distance “X” from the longitudinal axis “A” of the anchor as opposed to the body of the anchor being cut away to reveal a barb in the '552 patent. In this manner, a barb having a larger height is achieved without altering the dimensions of the body portion, which larger height more firmly secures the anchor of fastener 10 into body tissue as compared to the fastener disclosed in the '552 patent.

[0046] Unlike the applicator instrument for placing absorbable fasteners 10 disclosed in U.S. Pat. No. 5,997,552, previously incorporated by reference herein, the applicator according to the present disclosure is preferably adapted to fire 20 to 30 fasteners per instrument for use in either open and/or laparoscopic procedures. It is envisioned that the applicator instrument be either entirely disposable after use or be provided with a replaceable cartridge of fasteners which can be coupled to the end of a reusable applicator and replaced within a given procedure while the handle of such an applicator would still be disposable but would be reusable within a single procedure. While an alternate applier may be used, the fastener applier disclosed in the '552 reference can be used to apply the surgical fasteners disclosed herein.

[0047] By way of example, the general procedure of applying a mesh material during a hernia repair procedure, is to first create an access to the location of the hernia (i.e., incision and dissection) thereby exposing the hernia; then place a prosthetic mesh over the hernia defect; next fasten the mesh to the surrounding tissue by firing a plurality of absorbable fasteners 10 through the mesh and into tissue to thereby secure the mesh into place; and finally close the access wound.

[0048] Turning now to FIGS. 3 - 5 , an alternative embodiment of a surgical fastener in accordance with the present disclosure in shown generally as 200 . As seen in FIGS. 3 and 4 , fastener 200 includes a substantially conical body portion 202 depending from a circular head portion 204 . Conical body portion 202 includes a helical thread 206 commencing at a pointed distal tip 208 of body portion 202 and terminating at a distance spaced from head portion 204 . As the helical thread 206 advances from distal tip . 206 toward head portion 204 , the radial projection of the helical thread 206 from the body portion 202 increases. While the helical thread 206 is disclosed as commencing at the distal tip 208 , it is envisioned that the helical thread 206 can commence at a distance spaced from the distal tip 208 . In addition, head portion 204 can be provided with a recess or notch (not shown) formed in the center of the proximal surface thereof. The recess being configured to receive the distal tip 208 of an adjacent fastener 200 therein. In this manner, a series of fasteners 200 can be aligned in a tip-to-tail fashion with one another and share a common axis.

[0049] In use, fastener 200 is pressed into body tissue “T”, through surgical mesh “M”, until the entire body portion 202 of fastener 200 has passed through mesh “M” and has been buried in tissue “T”. Head portion 204 ensures that fastener 200 does not completely pass through mesh “M” thereby ensuring that mesh “M” is in contact with tissue “T”. Fastener 200 includes an arcuate tooth 210 projecting radially outwardly from the proximal end of helical thread 206 and oriented such that the curve of the arcuate tooth 210 is oriented to inhibit a rotation of fastener 200 which would remove fastener 200 from body tissue “T”.

[0050] Turning now to FIG. 5, a surgical fastener apparatus according to the present disclosure is shown generally as 300 . Similar to fastener 200 , surgical fastener apparatus 300 includes a pair of substantially conical anchors 302 each having a helical thread 304 commencing at a distal tip 306 of each anchor 302 and terminating at a proximal end surface 308 of each anchor 302 . Once again, the radial projection of the helical thread 304 on anchor 302 increases as the helical thread 304 advances from the distal tip 306 to the proximal end of the anchor 302 . While the helical thread 304 is disclosed as commencing the distal tip 306 , it is envisioned that the helical thread 304 can commence at a distance spaced from the distal tip 306 just as well. Anchors 302 are connected to one another by a suture tether 310 extending therebetween. As seen in FIG. 5 , the orientation of helical thread 304 on each anchor 302 is in the same direction. In this manner, as anchors 302 are being imbedded into body tissue and commence rotating in the direction of helical thread 304 , suture tether 310 on each anchor 302 will rotate in the same direction and not become tightened. The proximal end of each helical thread is provided with an arcuate tooth 312 , which arcuate tooth 312 is oriented such that after anchors 302 have been completely imbedded into the body tissue the tooth 312 will dig into the body tissue if the anchor is rotated in a direction which would remove the anchor from the body tissue. Similar to fastener 10 , surgical fastener apparatus 300 can be provided with a detent or recess 314 (see FIG. 6 ) formed in the proximal end surface thereof. In this manner, a series of fasteners 300 can be aligned in tip-to-tail fashion with one another in a fastener applier so that fasteners 300 share a common axis.

[0051] As seen in FIG. 6 , helical thread 304 is made up of a distal surface 316 and a proximal surface 318 joined together to form a sharp edge 320 . In addition, suture tether 310 is fixedly retained within anchors 302 , however, it is envisioned that suture tether 310 can be rotatably mounted to proximal surface 308 .

[0052] Fasteners 200 and 300 are also preferably made of medical grade absorbable materials, for example, Polyglycolic Acid (PGA) and Polylactic Acid (PLA). A critical feature of the presently disclosed absorbable fastener is that the absorbable fastener provide sufficient strength to retain a mesh material in place for a desired period of time. For example, in the case of applying a hernia repair mesh material, it is recommended that absorbable fasteners 200 or 300 remain in place retaining the mesh material for approximately 2-3 weeks and be absorbed into the body. tissue anytime after that. In addition, it is preferred that absorbable fastener 200 and that each anchor of fastener apparatus 300 are approximately 3 mm long, from the tip of distal end to the proximal end, and wherein the proximal end is approximately 1.5 mm in diameter. It is preferred that fastener 200 and fastener apparatus 300 are configured and dimensioned to avoid penetrating too far into the body tissue.

[0053] Fasteners 200 and 300 can be imbedded into body tissue by either pressing the fastener in to the tissue and allowing the thread on the fastener to automatically twist the fastener into the tissue, by providing a twisting applier which turns the fastener and thus the helical threads draw the fastener into the body tissue or by a combination of pressing and twisting.

[0054] By way of example only, and not to be considered limiting in any way, with reference to FIGS. 7 - 11 , a Lichtenstein repair method will now be described as performed using any of the absorbable surgical fasteners in accordance with the present disclosure. First, a 5 cm to 6 cm transverse incision is made within a Langer's line, beginning from the pubic tubercle. The external oblique aponeurosis is opened. As shown in FIG. 7 , the spermatic cord with its cremasteric covering, external spermatic vessels, and the genital nerve are freed from the inguinal floor and lifted with a Penrose drain. The spermatic cord is dissected free from the pubic bone area for approximately 2 cm medial to the pubic tubercle in order to make room for extending a prosthetic mesh beyond the pubic tubercle. The external oblique aponeurosis is dissected from the underlying internal oblique muscle and aponeurosis high enough to make room for a prosthesis that is 6 cm to 7 cm in height. The sac is then dissected from the cord beyond its neck and inverted into the properitoneal space without ligation or excision.

[0055] Referring to FIG. 8, a medial side of the mesh, is shaped to the patient's anatomy. A first absorbable fastener 10 , 200 or 300 is applied to the mesh to fix the mesh to the anterior rectus sheath where it inserts into the pubic bone. The absorbable fastener is placed approximately 2 cm medial to the pubic tubercle in order to be sure that the area is covered by the mesh. Additional absorbable fasteners 10 , 200 or 300 are placed therearound and end at the lateral border of the internal ring. The lower edge of the mesh is then anchored to the inguinal ligament using the same fasteners 10 , 200 or 300 around the surgical mesh and ending at the lateral border of the internal ring.

[0056] According to one method of the present disclosure, the absorbable fastener is secured into place by firing the fastener into the body tissue such that a first anchor of the surgical fastener penetrates through the surgical mesh and into the body tissue and such that a second anchor of the surgical fastener is implanted directly into the body tissue. In this manner, the suture tether of the fastener apparatus extends partially across the surgical mesh and partially across body tissue. In an alternative method, an absorbable fastener in accordance with the present disclosure, can be secured into place such that both anchors are imbedded into the body tissue and pass through the surgical mesh. If fastener 200 is used in the method, fasteners 200 are anchored into the body tissue solely through the mesh.

[0057] A slit is then made on the lateral end of the mesh, as seen in FIG. 9 , creating 2 tails—⅔ above and ⅓ below. The upper tail is then passed under the cord and pulled toward the head of the patient, placing the spermatic cord in between the 2 tails. The upper tail is then crossed over the lower one and held with a pair of hemostat, as seen in FIG. 10 . The tails are later sutured together and tucked under the external oblique aponeurosis, leaving 5 cm to 6 cm of mesh lateral to the internal ring.

[0058] While the upper edge of the mesh is fixed in place, care is taken to keep the mesh slightly relaxed. This laxity produces a dome-like ripple in the mesh to compensate for increased intra-abdominal pressure when the patient stands up from his or her recumbent position during the operation. If the mesh is kept completely flat, it becomes subject to tension when the patient stands up. This pulling effect on the mesh and the tissue, is illustrated when the mesh is kept flat as shown in FIG. 11 . The use of a surgical fastener in accordance with the present disclosure effectively eliminates the tension of the surgical mesh the anchors of the surgical fastener are relatively movable with respect to one another. In other words, one anchor is able to move with respect to the other anchor if needed as the patients body tissue shifts. In so doing, the tension on the mesh is reduced since the suture tether provides the mesh with some room to move since the individual anchors are moveable with respect to one another.

[0059] A Total ExtraPeritoneal Laparoscopic Hernia repair using fasteners 10 or 300 , in accordance with the present disclosure, will now be described. First, a skin incision is created and the fascia is incised. A balloon type distractor is then placed therein and distended in order to create an operative extraperitoneal space. Umbilical trocars and secondary trocars are then inserted into the extraperitoneal space and the space explored. The medial and lateral structures are then dissected and the spermatic chord identified. A surgical mesh is then cut to the desired size and shape such that a slit is provided in order to wrap the mesh on either side of the spermatic chord. The mesh is then laterally fixed in place using surgical fasteners 10 , 200 or 300 in order to anchor the mesh to the tranversus arch and the iliopubic tract. This step is repeated for the opposite side. The mesh is then medially fixed in place using additional fasteners 10 , 200 or 300 to the transversus arch and to Cooper's ligament or in the alternative, fix the mesh to the medial iliopubic tract. Finally, the incision is closed.

[0060] It is envisioned that fasteners 10 , 200 or 300 can be used in a TAPP repair method to replace suturing of the mesh both laterally and medially. In the TAPP repair method, fasteners 10 , 200 or 300 are used to secure the mesh in to place by penetrating the mesh and being anchored into the body tissue.

[0061] While each of the above described fasteners have been described as being used in connection with hernial repair surgery, it is envisioned that fasteners having a similar structure can be used in surgical procedures for fastening items to bone or cartilage. In such surgical procedures, the surgical fasteners can be made from surgical grade stainless steel, titanium or any other surgical grade material having sufficient strength to penetrate bone.

[0062] It will be understood that various modifications may be made to the embodiments of the presently disclosed surgical absorbable fastener apparatus and methods disclosed herein. Therefore, the above description should not be construed as limiting, but merely as exemplifications of preferred embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the present disclosure.