US20080208253A1 - Self-punching swivel anchor and method for knotless fixation of tissue - Google Patents

Abstract

A method and device for knotless fixation of tissue. A swivel anchor having a rotatable implant is used to capture suture for surgical tissue repair without requiring suture knots. The implant may be provided with a conical metal tip which is self-punching and avoids the need for pre-drilling a hole in bone. The implant includes a closed aperture to allow free sliding of a suture strand. The swivel anchor is secured in a hole in bone by advancing a fixation device, such as a cannulated interference screw, over the body of the implant.

Description

• This application 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 herein by reference.
FIELD OF THE INVENTION
• The present invention relates to methods and instruments for fixation of sutures and tissue to bone.
BACKGROUND OF THE INVENTION
• When soft tissue tears away from bone, reattachment becomes necessary. Various devices, including sutures, screws, staples, wedges, anchors and plugs have been used in the prior art to secure soft tissue to bone. Surgical methods utilizing suture anchors alone are disadvantageous for reattachment of large areas of detached tissue because they often do not allow good tissue to bone contact.
• Reattachment of soft tissue to bone typically requires the surgeon to pass suture material through selected tissue, form a plurality of surgical knots extracorporeally and then move the knots into position adjacent the desired tissue to be sutured. In such procedures, the surgeon must manually tie the knots on the suture strands after the suture is threaded through the selected tissues to be sutured. Knot tying during surgery, particularly arthroscopic surgery, is tedious and time-consuming. There is also a tendency for the knots to deform or collapse as the surgeon manually forces the knots down into the proper position. Also, the suture knots often are exposed to abrasion or cutting by sharp or rough areas along the walls of the bone canal into which anchors are typically inserted to provide fixation of tendon to bone.
• Accordingly, a need exists for an improved method for attaching soft tissue to bone which does not require multiple suture knots and which allows the tendon to remain securely in place until the ligaments naturally attach to bone.
SUMMARY OF THE INVENTION
• The instruments and methods of the present invention overcome the disadvantages of the prior art, such as those noted above, by providing a swivel implant at the distal end of a driver that securely engages and locks into a cannulated ribbed body of an interference plug or screw. The swivel implant includes a closed aperture for receiving a strand attached to a graft, such that the strand is able to freely slide through the aperture.
• In one embodiment of the invention, the strand is passed through the graft at desired points. A cannulated plug or screw is pre-loaded onto a driver provided with a swivel lock twist-in anchor at its distal end. The strand attached to the graft is passed through the aperture of the swivel implant located at the distal end of the driver. The distal end of the driver together with the implant is inserted directly into the bone. The driver may be rotated (in a clockwise direction, for example) to advance a screw over the anchor to complete insertion.
• 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. 1-6 depict a series of steps of shoulder repair using a plurality of swivel anchor devices according to the present invention.
• FIG. 7 illustrates various views of the driver assembly of the present invention.
• FIGS. 8 and 9 illustrate the swivel implant and traction suture.
• FIG. 10 is an enlarged view of the fixation device (cannulated screw) used in the present invention.
• FIG. 11 illustrates various views of a swivel anchor with a metal tip which avoids the need to pre-drill a hole in bone.
• FIGS. 12 and 13 provide additional illustrations of the swivel anchor assembly of the present invention, and the swivel anchor inserted in a bone socket, respectively.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
• The present invention provides apparatus and methods for knotless tissue fixation using a swivel anchor device.
• FIG. 1 illustrates a side view of a human shoulder of a patient undergoing a rotator cuff repair in accordance with an exemplary embodiment of the present invention. The patient may be positioned in the beach chair position using the Arthrex Beach Chair Lateral Traction Device or in a lateral decubitus position using the Arthrex 3-Point Shoulder Distraction System. Access to the subacromial space is facilitated with a variety of cannulas.
• First, and as illustrated inFIG. 1, the mobility of the tear is assessed using, for example, atissue grasper10 such as the Arthrex KingFisher™ Suture Retriever/Tissue Grasper, to determine whether a U or L-shaped component exists. Where large tears extend to the superior aspect of the glenoid, margin convergence suturing is performed to reduce volume and strain on the repair. Subsequently, the length and width of the rotator cuff footprint is assessed and a bleeding bed for enhanced tendon to bone healing may be formed. This may be accomplished with a burr to perform a light dusting of the greater tuberosity, or by using a chondro pick to microfracture the footprint and maximize vascular channels.
• FIG. 2 illustrates the preparation of two pilot holes for two swivel anchors that will be inserted in the medial row. A punch may be employed adjacent to the articular margin of the humerus and at about 45° angle to form the two pilot holes.
• Subsequent to the formation of the pilot holes, and as shown inFIGS. 3 and 4, aswivel implant30, loaded with a strand ofsuture tape40, preferably Arthrex FiberTape, is placed in the medial pre-formedhole32. Arthrex FiberTape is a high strength suture tape which is braided and rectangular-like in cross section and is disclosed in U.S. Patent Application Publication No. 2005/0192631, the disclosure of which is incorporated by reference herein. However, the anchor of the present invention can be used with any type of flexible material or suture. The driver is then rotated to advancescrew42 downshaft20 to secure the implant and suture in the bone hole. More specifically, as shown inFIG. 4a, thescrew42 is advanced by holdingthumb pad50 as thedriver handle22 is turned clockwise. An Arthrex FiberLink and an Arthrex Scorpion suture passer44, are used to shuttle both tails of the suture tape through the rotator cuff34 simultaneously. This procedure is followed for both medial swivel anchors.
• Referring toFIG. 5, one tail ofsuture tape40 from each medial swivel anchor is retrieved and loaded through the eyelet of anotherswivel implant30, and that implant is installed in then inserted into a preformed lateral bone socket. The tension of thesuture tape40 is adjusted if necessary. The swivel anchor driver is then rotated in clockwise direction as before to advance thescrew42 over the implant to complete insertion. This step is repeated in another lateral bone socket with the other tails of suture tape from each medial anchor. The tails of thesuture tape40 are then cut, one at a time, to complete the construct as shown inFIG. 6. The method is analogous to the method disclosed in U.S. Patent Application Publication No. 2007/0191849, the entire disclosure of which is incorporated by reference herein.FIGS. 12 and 13 provide additional illustrations of the swivel anchor assembly and the anchor inserted in a bone socket, respectively.
• The swivel anchor and instruments of the present invention are now described in greater detail. As shown inFIGS. 7(a)-(f), adriver68 is used to install the knotless fixation devices with a swiveling implant.Driver68 features a thin cannulatedrod20 passing slidably and rotatably through a cannulated driver assembly. The tip of thincannulated rod20 is adapted to acceptswivel anchor implant42 within the cannulation at its tip, preferably via a snap fit.Cannulated rod20 has a hexagonal outer surface for receiving anchor body (preferably a screw)42 having a corresponding cannulation.FIG. 10 illustrates a detailed view of thecannulated screw42.
• During installation of the knotless anchor having aswiveling implant30, thescrew42 is first inserted ontocannulated rod20 of thedriver68. As shown inFIGS. 7(a) and (b),screw42 is loaded ontorod20 and then fully seated on the shaft end of the driver.FIG. 7(c) illustrates theswivel anchor implant30. As shown inFIGS. 8-9, traction sutures71 extending from the proximal end of theswivel anchor implant30 are threaded through the cannulation of the driver68 (see alsoFIG. 7(c)). These traction sutures71 prevent inadvertent separation of theimplant30 from the driver during insertion, but they can be used subsequently for additional tie-down of the tendon after the driver is removed. Subsequently, theswivel anchor implant30 is seated on the driver tip and until advanced until it snaps onto place (FIG. 7(d)). A protective tube94 (FIG. 7(e)) may be placed over the tip of the assembly for shipping purposes. The traction sutures71 may be looped around the driver handle, as shown inFIGS. 7(f) and (g), and secured in acleat98 to prevent the implant200 from becoming prematurely detached from the driver.
• The knotless fixation device of the present invention advantageously minimizes or eliminates the need to tie knots. The use of such a swivel anchor also provides secure fixation of the suture construct—the secure suture construct results from the suture being pushed into a hole and held tightly by an anchors.
• In the preferred embodiment of the present invention, as mentioned above, suture tape is used with the swivel anchor to fix tissue to bone. However, the swivel anchor of the present invention can be used with any type of flexible material or suture. In another preferred embodiment, an allograft or biological component may be used instead of suture or tape. The allograft or biological component may be comprised of tendon or pericardium, for example, which provides improved tissue repair. In yet additional embodiments, any combination of suture, suture tape, and allograft or biological component may be employed, depending on the characteristics of the specific surgical repair and/or as desired.
• FIG. 11 illustrate aswivel implant500 which is provided with a pointed metal tip to facilitate insertion of the implant without the need to pre-drill or pre-form a hole in the bone. The conical configuration of the most distal end pointedtip550 allows the implant to undergo a self-punching operation, eliminating any need to pre-drill a hole in the bone. The conical configuration of the most distal end of the pointedtip implant550 also provides suture fixation strength, as well as accelerated graft/tendon healing to bone. Thepointed tip implant550 may be detachable from the driver.
• As illustrated inFIGS. 11(a)-(e), pointedtip implant500 is provided with ametal tip550 and an eyelet oraperture555 for receiving suture or suture tape.Pointed tip implant550 is also provided, at its most distal end, with aconical portion551 which allows direct advancement of the implant (by simply tapping the device with a mallet, for example) without the formation of a pilot hole in bone. Preferably, theconical portion551 of the implant is formed of titanium or titanium alloy. In a preferred embodiment, eyelet oraperture555 is also formed of titanium or similar material, to withstand impaction forces during the graft fixation procedure.
• Although the present invention has been described in relation to particular embodiments thereof, many other variations and modifications and other uses will become apparent to those skilled in the art. It is preferred, therefore, that the present invention be limited not by the specific disclosure herein.

Claims (17)

1. A method of tissue fixation comprising:

providing a suture;

securing the suture to the tissue to be fixated; and

anchoring the suture into the bone socket using a swivel implant and a fixation device, thereby providing tissue fixation.

2. The method ofclaim 1, wherein the fixation device is an interference screw or a plug.

3. The method ofclaim 1, wherein the swivel implant has a conical portion terminating at a pointed tip at its most distal end.

4. The method ofclaim 1, wherein the swivel implant has a closed aperture at its distal end.

5. The method ofclaim 1, further comprising the step of capturing the suture attached to the graft with the swivel implant.

6. The method ofclaim 5, wherein the step of capturing the suture further comprises passing the suture through a closed aperture of the swivel implant.

7. The method ofclaim 6, wherein the closed aperture has an eyelet configuration.

8. The method ofclaim 1, further comprising the steps of preloading the fixation device on a driver and, subsequently, providing the swivel implant at a distal end of the driver.

9. A suture anchor comprising:

an anchor body; and

an anchor tip rotatably attached to the anchor body.

10. The suture anchor ofclaim 9, wherein the anchor tip has a closed aperture.

11. The suture anchor ofclaim 9, wherein the anchor tip is a metal tip.

12. The suture anchor ofclaim 9, wherein the suture anchor is configured to allow rotational insertion without causing excessive twisting and knotting of a suture captured in the anchor tip.

13. The suture anchor ofclaim 9, wherein the anchor tip is configured to capture a suture.

14. The suture anchor ofclaim 9, wherein the anchor body has a cylindrical configuration.

15. The suture anchor ofclaim 9, wherein the anchor tip is detachable.

16. The suture anchor ofclaim 9, further comprising a fixation device for securing the suture anchor in bone.

17. The suture anchor ofclaim 16, wherein the fixation device is a cannulated interference screw or a plug.

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