US20090192546A1 - Fenestrated suture anchor and method for knotless fixation of tissue - Google Patents

Abstract

A fenestrated suture anchor for fixation of tissue to bone. In a preferred embodiment, the suture includes an implant, such a swivel implant with a forked tip for capturing suture. The implant is secured in a hole in bone by advancing a fixation device, such as a cannulated interference screw, to engage and fully seat the implant. The cannulated fixation device is provided with a plurality of openings or fenestrations of various dimensions and geometries to provide multiple pathways through the anchor (i.e., though the interior of the body and through the fenestrations) to allow blood to flow to increase the healing zone, for example, for rotator cuff repair, while also promoting bone in-growth.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS
• This application is a continuation-in-part of U.S. application Ser. No. 12/043,008, filed on Mar. 5, 2008, which in turn is a continuation-in-part of U.S. application Ser. No. 11/802,057, filed on May 18, 2007, which claims the benefit of U.S. Provisional Application Ser. No. 60/801,097, filed on May 18, 2006, the entire disclosures of which are incorporated by reference herein. This application is also a continuation-in-part application of U.S. application Ser. No. 11/392,798, filed on Mar. 30, 2006, which in turn claims the benefit of U.S. Provisional Application Ser. No. 60/666,518, filed on Mar. 30, 2005, the entire disclosures of which are also incorporated by reference herein.
FIELD OF THE INVENTION
• The present invention relates to surgical fixation and, more particularly, to methods of conducting anatomical tissue repair, such as ligament repair and reconstruction, using a fenestrated suture anchor.
BACKGROUND OF THE INVENTION
• Securing suture during surgery can be difficult and demanding. Various suture constructs have been developed in an effort to avoid the need to tie knots in suture, particularly during arthroscopic surgery. For example, U.S. Pat. No. 6,143,017 to Thal discloses tissue fixation using a free-standing continuous suture loop that is snagged by an anchoring device. While it appears that tissue can be bound to bone according to the Thal teachings, it is not evident how to accomplish in situ surgical refinements such as adjustment of the loop length or tension on the repaired tissue. Accordingly, there exists a need in the art for improved technology for knotless tissue fixation. A need also exists for a knotless suture anchor with fenestrated configuration that promotes healing of tissue.
SUMMARY OF THE INVENTION
• The present invention provides apparatus and methods for anatomical tissue repair and reconstruction, using a fenestrated suture anchor for knotless tissue fixation. In one method of tissue fixation, a swivel implant is used to capture a suture chain formed of at least two loops formed of high strength suture. A driver is provided direct the tip of the swivel implant to capture loops of the suture chain. The swivel implant is locked and secured in bone by inserting a cannulated fixation device (for example, an interference plug or screw) over the implant. The cannulated fixation device is provided with a plurality of openings or fenestrations of various dimensions and geometries to provide multiple pathways through the device (i.e., though the interior of the body and through the fenestrations) to allow blood to flow to increase the healing zone, for example, for rotator cuff repair, while also promoting bone in-growth.
• Other features and advantages of the present invention will become apparent from the following description of exemplary embodiments of the invention described with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
• FIGS. 1-8 depict a series of subsequent steps of shoulder repair using a single-row technique with a swivel suture anchor according to the present invention.
• FIGS. 9-16 depict a series of subsequent steps of shoulder repair using a double-row technique with a swivel suture anchor according to the present invention.
• FIG. 17 illustrates various views of a driver assembly comprising a rod, an inserter member, a threaded gauge and an end piece, according to the present invention.
• FIG. 18 illustrates various views of the inserter member of the driver assembly ofFIG. 17.
• FIG. 19. illustrates various views of the threaded gauge with thumb pad of the driver assembly ofFIG. 17.
• FIG. 20 illustrates various views of the rod of the driver assembly ofFIG. 17.
• FIG. 21 illustrates various views of a swivel implant according to the present invention.
• FIG. 22 illustrates various views of a fixation device according to a first embodiment of the present invention and used in conjunction with the swivel implant ofFIG. 20 and the driver ofFIG. 17.
• FIGS. 23-26 illustrate various views of a fixation device with fenestrations according to a second embodiment of the present invention and used in conjunction with the swivel implant ofFIG. 20 and the driver ofFIG. 17.
DETAILED DESCRIPTION OF THE INVENTION
• The present invention provides apparatus and methods for knotless tissue fixation using a swivel suture anchor. In a preferred method, the swivel suture anchor is used with a suture chain formed of at least two loops of suture, preferably high strength suture. The loops of the chain are captured by mounting the swivel implant on a driver. The driver is also used to engage and lock the swivel implant in a hole in bone by inserting a cannulated fixation device (for example, an interference plug or screw) over the anchor.
• The present invention also provides a method for knotless fixation of anatomical tissue during surgical applications by employing a swivel suture anchor. Suture chains used in accordance with the present invention are described in detail in U.S. Application Publication No. 2006/0259076, the entire disclosure of which is incorporated by reference herein. The term “chain” is used in the specification and claims to refer to exemplary embodiments of the invention. A “chain” in this context refers broadly to a suture construct formed of a series of suture loops. The loops can be, but need not be, interlinked. In this manner, the term “chain” as used in this application includes, but need not be limited to, the commonly understood definition in which links or rings are fitted into one another. Rather, the chains of the present invention can include two or more loops that are connected together. Each loop preferably has a fixed perimeter. The suture can be interlaced, rather than knotted, as described further below, to establish and maintain loop geometry. Preferably, all loops are similar in size.
• Referring now to the drawings, where like elements are designated by like reference numerals,FIGS. 1-16 illustrate two surgical procedures of approximating tissue (for example, a torn tendon) to bone according to exemplary embodiments of the present invention. For simplicity, the invention will be described below with reference to fixation of the rotator cuff; however, the invention is not limited to this exemplary embodiment and has applicability to fixation of tissue in general, such as, for example, fixation of torn tendons in ACL reconstructions of the knee or in fixation of any tendon to bone.
• Method steps of tissue fixation according to exemplary embodiments of the present invention are depicted schematically inFIGS. 1-16. As described in more detail below,FIGS. 1-8 illustrate sequential steps during a rotator cuff repair using a knotless single row technique andFIGS. 9-16 illustrate sequential steps during a rotator cuff repair using a knotless double row technique. Both techniques will be described with reference to driver assembly100 (FIGS. 17-20), swivel lock anchor200 (FIG. 21) and fixation device300 (FIG. 22).
• Although the single and double row techniques are described below with reference to specific instruments sold by Arthrex, Inc., the assignee of the present application, and with reference to a series of specific steps and devices used during the surgical tissue fixation, it should be understood that the invention is not limited to the specific disclosure of these embodiments and contemplates modifications and variations that are apparent to those skilled in the art. Accordingly, the invention must not be limited to the specific embodiments detailed below, as they are only exemplary in nature.
• Knotless Single Row Repair Technique—FIGS. 1-8
• FIGS. 1-8 illustrate a series of subsequent steps in shoulder repair for a single-row repair technique using a swivel suture anchor according to the present invention.
• The mobility of the tear is assessed using a suture retriever/tissue grasper105, such as the Arthrex KingFisher™ Suture Retriever/Tissue Grasper, as shown inFIG. 1. In the case of a large U-shaped tear, margin convergence suturing may be required before approximation. Then, a shaver, high-speed burr, or chondro pick is used to prepare a bleeding bone bed.
• As shown inFIG. 2, the non-linked,free end10aof asuture chain10, such as the Arthrex FiberChain, is passed through therotator cuff150 using asuture passer110, such as the Arthrex Scorpion™ Suture Passer, through a cannula, such as an Arthrex 5.75 mm Crystal Cannula. Next, the suture is retrieved through the same cannula.
• Then thefree end10aofsuture chain10 is passed through theterminal link10bat its opposite end, as shown inFIG. 3. Theloop10bis cinched down by pulling on thefree end10aof thesuture chain10. The tip of the cannula may be used to help seat the suture chain loop securely against therotator cuff150. A suture retriever/tissue grasper105 may be useful to ensure that the loop has been fully tightened. Thesecond suture chain11 is passed through therotator cuff150, the free end passed through the terminal loop, and the loop cinched in the same manner as for thefirst suture chain10.
• As shown inFIG. 4, thesuture chain10,11 is used as a traction suture to determine the desired anchor location adjacent to the rotator cuff margin and abone socket155 is punched through a superolateral percutaneous portal with apunch115, such as the Arthrex 5.5 mm Bio-Corkscrew FT Punch. Asecond bone socket155 is also formed in the same manner for thesecond fiber chain11.
• As shown inFIG. 5, both suture chain ends10a,11aare retrieved through the lateral portal. Theswivel implant200 of the present invention is introduced through the percutaneous superolateral portal and captures the third link10cfrom the free margin of therotator cuff150. The link10cis captured by the forkedanchor tip250 of the anchor200 (seeFIG. 21). In a preferred embodiment, each link in thesuture chain10 is approximately 6 mm in length; therefore, since the total length of theswivel implant200 is 18 mm, capturing the third link10cfrom the cuff edge will usually position the cuff directly at the edge of thebone socket155 and perfectly tension thesuture chain10 and therotator cuff150 segment that it spans, when theanchor tip250 pushes thesuture chain10 to the bottom of thebone socket155.
• The tissue tension is then evaluated, as shown inFIG. 6. Thedriver assembly100 is advanced into thebone socket155 and thesuture chain10 is pushed toward the bottom of thesocket155 until theanchor body225 contacts the bone. If the tension is not adequate, thedriver100 is removed from thebone socket155 by pulling on the free end of the suture chain10 (to release any wedging of the swivel-tip250) at the same time that thedriver assembly100 is withdrawn. Then the adjacent, more proximal link is instead captured. If the tension is too great to fully insert thedriver100 to the bottom of thebone socket155, thedriver100 is removed and the adjacent, more distal link is captured. Then thedriver100 is reinserted to the base of the bone socket. The forkedtip250 of theswivel implant200 is held to the driver with a zero retention suture cleated at the driver's proximal end.
• Fixation device300, such as a screw, is advanced bydriver assembly100 by holding thethumb pad50 as theinserter handle22 is turned clockwise, as shown inFIG. 7. When the swivel anchor construct400 is fully seated, theshaft225 of theswivel implant200 is fully engaged by thefixation device300 to optimize the stability of theswivel implant construct400. The swivel anchor construct400 comprisesswivel implant200 andfixation device300. The tip retention suture is unwound from the cleat at the back of thedriver handle22 and thedriver assembly100 is removed. Then, one limb of the retention suture is pulled to fully remove it from the implant.
• The insertion steps are repeated for the second swivel anchor construct400 to obtain the final suture/anchor construct, shown inFIG. 8. The free suture ends10a,11aare cut with a suture cutter, such as the Arthrex open ended FiberWire Suture Cutter, so that they are flush with the edge of thebone socket155.
• Knotless Double Row Repair Technique—FIGS. 9-16
• FIGS. 9-16 illustrate a series of subsequent steps in shoulder repair for a double-row repair technique using a swivel suture anchor according to the present invention.
• The mobility of the tear is assessed using suture retriever/tissue grasper. In the case of a large U-shaped tear, margin convergence suturing may be required before approximation of the tendon. A shaver, high-speed burr, or chondro pick is used to prepare a bleeding bone bed. Then, as shown inFIG. 9,pilot holes160 are prepared for two suture anchors120, such as Arthrex Bio-Corkscrew FT suture anchors, that will comprise the medial row through a percutaneous superolateral portal. Apunch115, such as the Arthrex 5.5 mm Bio-Corkscrew FT Punch, is advanced to the laser line at a 45° “deadman” angle, adjacent to the articular margin of the humerus to form the pilot holes160. Tapping is seldom, but may be, necessary.
• As shown inFIG. 10, both suture anchors120 are placed. In a preferred embodiment, the suture anchors120 come preloaded withsuture chain10.
• Then, as shown inFIG. 11, the suture leader is retrieved from one of thesuture chain10 strands through the lateral portal and is loaded onto asuture passer110, such as the Arthrex Scorpion Suture Passer. Thesuture chain10 is passed through therotator cuff150 approximately 15 mm from the free margin of therotator cuff150. This step is then repeated for thesecond suture chain11.
• As shown inFIG. 12, both suture chain suture ends10a,11aare retrieved through the lateral portal and are tensioned to bring the cuff into contact with the medial portion of the footprint. The tip of the cannula may be used to push the tendon against the footprint. Then twobone sockets155 are formed for the lateralrow swivel implants200 using apunch115. These twobone sockets155 should be adjacent to the lateral margin of thecuff150 when thecuff150 is appropriately tensioned by the two previously placedsuture chains10,11.
• As shown inFIG. 13, theswivel implant200 is introduced through the percutaneous superolateral portal, capturing the third link10cfrom the free margin of therotator cuff150. The link10cis captured by the forkedanchor tip250 of the swivel implant200 (seeFIG. 21). In a preferred embodiment, each link in thesuture chain10,11 is approximately 6 mm in length; therefore, since the total length of theswivel implant200 is 18 mm, capturing the third link from the cuff edge will usually position the cuff directly at the edge of thebone socket155 and perfectly tension thesuture chain10 and the rotator cuff segment that it spans when theanchor tip250 pushes thesuture chain10 to the bottom of thebone socket155.
• The tissue tension is then evaluated, as shown inFIG. 14. Thedriver assembly100 is advanced into thebone socket155 and thesuture chain10 is pushed toward the bottom of thesocket155 until theanchor body225 contacts the bone. If the tension is not adequate, the driver is removed from the bone socket by pulling on the free end of the suture chain10 (to release any wedging of the swivel-tip250) at the same time that thedriver assembly100 is withdrawn and the adjacent, more proximal link is instead captured. If the tension is too great to fully insert the driver to the bottom of thebone socket155, thedriver assembly100 is removed and the adjacent, more distal link is instead captured. Then thedriver100 is reinserted to the base of thebone socket155.
• Fixation device300, e.g., a screw, is advanced by holding thethumb pad50 as theinserter handle22 is turned clockwise, as shown inFIG. 15. When theswivel anchor400 is fully seated, theshaft225 of theswivel implant200 is fully engaged by the body of thefixation device300 to optimize the stability of theswivel implant construct400. As previously stated, the swivel anchor construct400 comprisesanchor200 andfixation device300. The tip retention suture is unwound from the cleat at the back of thedriver handle200 and thedriver100 is removed. One limb of the retention suture is pulled to fully remove it from the implant.
• The steps ofFIGS. 13-15 are then repeated for the second swivel implant construct400 to obtain the final construct, shown inFIG. 16. The free suture ends are cut with a suture cutter so that they are flush with the edge of thebone socket155.
• In addition to the above exemplary embodiments, the invention may also be used for a side-to-side closure of soft tissue using asuture chain10. This method includes using thesuture chain10 to perform the side-to-side closure of the soft tissue with a final step of anchoring a chain link at the lateral aspect of the repair to bone using an anchor, such asanchor200. The anchoring step is the same as that illustrated in the first two embodiments. Furthermore, if the soft tissue split to be repaired overlies bone for its entire length, a suture anchor, similar tosuture anchor120, may be inserted into bone at the medial aspect of the repair, a side-by-side margin convergence is implemented using the suture chain in a “shoelace-type” stitch, and the suture chain is anchored at the lateral aspect of the repair to bone using an anchor, such asanchor200.
• Reference is now made toFIGS. 17-22, which illustrate details of the driver assembly100 (FIGS. 17-20), the swivel implant200 (FIG. 21) and the fixation device300 (FIG. 22). As illustrated inFIGS. 17-20,driver assembly100 comprises a cannulateddriver20 includingshaft25 and inserter handle22; tube orrod30 that passes slidably and rotatably through the cannulateddriver20; threadedgauge40 including a cannulatedbody42 andthumb pad50; andtip44.FIG. 17 illustrates thedriver assembly100 both in assembled (A) and unassembled (B) form.FIG. 18 provides a more detailed view of the cannulateddriver20 of thedriver assembly100.FIG. 19 provides a more detailed view of the threadedgauge40 of thedriver assembly100.FIG. 20 provides a more detailed view of therod30 of thedriver assembly100.
• FIG. 21 illustrates various views ofswivel implant200. During installation ofswivel implant200, theimplant body225 is assembled onto the operational end of thedriver100. Theimplant tip250 is threaded or otherwise attached onto the tip of thin rod ortube30. As detailed above, forkedtip250 is used to capture asuture chain10,11 (that has been laced through a shoulder ligament, as shown in the two exemplary embodiments above) for installation into apre-drilled hole155 in bone. Theimplant200 has a threadedbody225 and a detachable forkedtip250. The forkedtip250 may be rotatably attached to theimplant body225. This enables rotational insertion of theimplant200 without causing excessive twisting and knotting of thesuture chain10,11 by the forkedtip250.
• FIG. 22 illustrates various views of a fixation device300 (for example, a cannulated interference screw) that is employed in conjunction with thedriver assembly100 and theswivel implant200. Preferably, thefixation device300 is preloaded on thedriver assembly100. As described above with reference to the two exemplary embodiments, thefixation device300 is advanced into thebone socket155 by holding thethumb pad50 as theinserter handle22 is turned clockwise. When thefixation device300 is fully seated, theshaft225 of the forkedswivel implant200 is fully engaged by thefixation device300 to optimize the stability of theswivel implant construct400. As previously stated, the swivel implant construct400 is composed ofanchor200 andfixation device300.
• In the two exemplary embodiments detailed above,suture anchor400 is an Arthrex SwiveLock™ (swivel suture anchor). However,suture anchor400 may be also a bone anchor or an Arthrex Push-Lock™-type anchor including a forked tip in order to capture a given link of the suture chain. Alternatively, thesuture chain10,11 passed through the tissue can be secured either using a single anchor or a plurality of anchors. In addition, various anchors, such as those noted above and others, may be used interchangeably with only slight variations in the above procedure. For example, thesuture chain10,11 can be secured by capturing two of the chain loops in forked tines prior to insertion of the anchor or anchors.
• Further, regular suture may be used in addition to the suture chains of the present invention. In this case, thefirst suture anchor120 of the double row embodiment will be pre-loaded with regular suture (for example, the Arthrex BioCorkscrew™ or Arthrex BioCorkscrew-FT™, disclosed in U.S. Application Publication No. 2007/0060922). In an exemplary embodiment using regular suture, the technique is similar to the one described above, except that the lateral fixation is accomplished by capturing the suture limbs (rather than chain-links) in the fork of theimplant200 and tensioning the suture as theimplant200 is placed. This relies on interference fixation of the suture between theimplant200 and the bone.
• As described above, the swivel anchor and suture chain assembly of the present invention has application in surgical tissue repair, for example, in conjunction with one or more bone anchors. Tension on repair constructs is adjustable through selection of the chain link or links to be snagged by a bone anchor.
• FIGS. 23-26 illustrate various views of anotherexemplary fixation device500 of the present invention that is employed in conjunction with thedriver assembly100 and theswivel implant200. Thefixation device500 is similar to thefixation device300 ofFIG. 22, but differs from it in that thefixation device500 is provided with a plurality of openings orfenestrations505 provided on the outer surface of the body of the device. The openings orfenestrations505 may have various dimensions and geometries provide multiple pathways for w blood to pass through the device (i.e, through the fenestrations and up through the cannulation) and, therefore, to the repair site to promote healing. The fenestrations also promote in-growth of bone. The decreased mass of the device500 (resulting from the fenestrations) further promotes healing and in-growth.
• Preferably, thefixation device500 is preloaded on thedriver assembly100. As described above with reference to the three exemplary embodiments, thefixation device500 is advanced into thebone socket155 by holding thethumb pad50 as theinserter handle22 is turned clockwise. When thefixation device500 is fully seated, theshaft225 of the forkedswivel implant200 is fully engaged by thefixation device500 to optimize the stability of the swivel anchor construct (composed ofimplant200 and fixation device500).
• As illustrated inFIGS. 23-26, thefixation device500 includes a cannulatedbody512 in the form of a tapered cylinder having aproximal end513 and adistal end515. Acontinuous thread520 wraps around cannulatedbody512 in a clockwise direction, as shown. As shown inFIG. 25, thedistal end515 of theinterference screw500 terminates in an exposed, flat surface provided with an opening516. Theproximal end513 of theinterference screw500 terminates in adrive socket517 that allows a driver to seat snuggly in the drive socket to allow manipulation and installation of the interference screw into the bone socket, while fully engaging the shaft of the swivel implant200 (as detailed above with reference to interference crew300). As shown inFIG. 26,drive socket517 may be configured to be used with a traditional hex drive screwdriver. Although thedrive socket517 has been described as having hexagonal shape, the drive socket may also have a Delta drive configuration or a cruciform shape, among others, that allows the driver to rotationally engage the interference screw, to turn simultaneously with the driver.
• Thefixation device500 of the present invention may be formed of a biocompatible and/or biosorbable material. Preferably, screw500 is formed of a bioabsorbable material, such as poly-(L-lactic acid) (PLLA), poly-(D,L-lactide), and poly glycolic acid (PGA), for example, or other bioabsorbable, non-metallic materials, which may be especially tailored for hardness, tensile strength and compressive strength. Alternatively,fixation device500 may be formed of titanium, titanium alloy, stainless steel or stainless steel alloy. Other biocompatible materials which could be used include plastics, allograft bone and inert bone substitute materials.
• A growth material may be advanced through the cannulated driver and into thescrew500 by employing a plunger, for example. As the driver is pulled out, the plunger pushes the flow material through the cannulation of the driver and into the body of thescrew500. The growth material will subsequently harden to allow better fixation of theinterference screw500 against the bone and the shaft of theswivel implant200.
• The growth material may be any solid, semi-solid, viscous, flowable, gel or elastic composition or mixture that allows its easy manipulation and insertion into thebody512 of theinterference screw500. The growth material may contain growth factors such as autogenous growth factors, for example platelet-rich plasma (PRP), optionally in combination with hyaluronic acid (HY acid) and/or with a coagulant such as thrombin.
• The term “growth factor” as used in the present application is intended to include all factors, such as proteinaceous factors, for example, which play a role in the induction or conduction of growth of bone, ligaments, cartilage or other tissues associated with bone or joints. In particular, these growth factors include bFGF, aFGF, EGF (epidermal growth factor), PDGF (platelet-derived growth factor), IGF (insulin-like growth factor), TGF-β. I through III, including the TGF-β. superfamily (BMP-1 through 12,GDF 1 through 12, dpp, 60A, BIP, OF).
• Optionally, the growth material may comprise additional osteoconductive bone adhesives, calcium carbonate, fatty acids, lubricants, antiseptic chemicals and/or antibiotics. In this case, other solution excipients such as buffer salts, sugars, anti-oxidants and preservatives to maintain the bioactivity of the growth material and a proper pH of the growth material may be also employed. The additional lubricants and/or the antiseptic and/or the antibiotic will typically be present in the growth material in a predetermined concentration range, which will be dependent upon the particular bone site and application, as well as the specific activity of the antiseptic and/or the antibiotic.
• The above description and drawings illustrate preferred embodiments which achieve the objects, features and advantages of the present invention. It is not intended that the present invention be limited to the illustrated embodiments, but rather only by the appended claims.

Claims (12)

1. A method of tissue fixation, comprising:

providing a suture;

securing a first portion of the suture to the tissue to be fixated;

providing a bone socket; and

anchoring a second portion of the suture into the bone socket using a cannulated fixation device provided with side fenestrations.

2. The method ofclaim 1, wherein the step of anchoring the suture into the bone socket comprises capturing the suture with an implant, inserting the implant into the bone socket and inserting the fixation device into the bone socket to engage and fully seat the implant in bone.

3. The method ofclaim 2, wherein the implant is a swivel implant.

4. The method ofclaim 1, wherein the cannulated fixation device comprises a ribbed, push-in device.

5. The method ofclaim 1, wherein the cannulated fixation device comprises a threaded, screw-in device.

6. A suture anchor, comprising:

a cannulated fixation device provided with side fenestrations; and

an implant for capturing a suture.

7. The suture anchor ofclaim 6, wherein the implant has a forked distal end for capturing the suture.

8. The suture anchor ofclaim 7, wherein the implant is configured to allowed rotational insertion without causing excessive twisting and knotting of a suture captured in the forked end.

9. The suture anchor ofclaim 6, wherein the fixation device has a threaded body.

10. The suture anchor ofclaim 6, wherein the fixation device has a ribbed body.

11. The suture anchor ofclaim 6, wherein the fixation device is a cannulated interference screw provided with side fenestrations.

12. A suture anchor comprising a cannulated body, the cannulated body being provided with side fenestrations.

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