# Patent

## Title
Method of anchoring a suture

## Abstract

Devices and methods are presented for securing a suture to facilitate a surgical procedure.

## Background
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Application No. 61/764,485, filed Feb. 13, 2013, which is hereby incorporated by reference.


FIELD OF THE INVENTION
The invention relates to methods for anchoring sutures such as for anchoring a suture to a bone in an orthopedic surgical procedure.
BACKGROUND
Various conditions affecting a patient may require surgical intervention involving anchoring a suture for example to repair or reconstruct soft tissue or to connect adjacent bony structures.
SUMMARY
The present invention provides devices and methods for securing a suture to facilitate a surgical procedure.
In one aspect of the invention, a method of securing first and second suture limbs relative to a bone, includes passing first and second suture limbs through a bone tunnel; passing the first suture limb through a cannulated anchor; inserting the anchor into the bone tunnel to trap the second suture limb between the anchor and bone tunnel in interference relationship; and securing the first suture limb.
In another aspect of the invention, a method of tethering first and second bones together, includes anchoring a first suture anchor to the first bone; passing a suture from the first suture anchor through a bone tunnel in the second bone; and inserting a second suture anchor into the bone tunnel in the second bone to secure the suture between the second suture anchor and bone tunnel in interference relationship.



BRIEF DESCRIPTION OF THE DRAWINGS
Various examples of the present invention will be discussed with reference to the appended drawings. These drawings depict only illustrative examples of the invention and are not to be considered limiting of its scope.
FIG. 1 is a perspective view of an illustrative anchor useable with the method of the present invention;
FIG. 2 is a front elevation view of the anchor of FIG. 1;
FIG. 3 is a left side elevation view of the anchor of FIG. 1;
FIG. 4 is a right side elevation view of the anchor of FIG. 1;
FIG. 5 is a front elevation view of an illustrative driver useable with the anchor of FIG. 1;
FIG. 6 is a front elevation view of an illustrative suture threader useable with the anchor and driver of FIGS. 1 and 5;
FIG. 7 is a front elevation view of the anchor of FIG. 1, driver of FIG. 5, and threader of FIG. 6 assembled for use;
FIGS. 8 and 9 are front elevation views illustrating steps in a method according to the present invention;
FIG. 10 is a partial sectional view illustrating a step in the method of FIGS. 8 and 9;
FIGS. 11-15 are cutaway views of a human foot illustrating steps in a method according to the present invention.



DESCRIPTION OF THE ILLUSTRATIVE EXAMPLES
FIGS. 1-4 depict a cannulated interference anchor 100. The anchor 100 includes an elongated body 102 extending between a proximal end 104 and a distal end 106 along an axis 108. An axial passage 110 extends longitudinally through the body between the proximal and distal ends 104, 106. Optional fixation projections 112 extend radially outwardly from the body 102. In the illustrative example of FIGS. 1-4 the anchor 100 is an interference screw having a coaxial bore and a helical thread spirally about the outside of the body. The axial passage 110 has a non-circular driver engaging profile 114. For example the profile 114 may have at least one flat side and is preferably polygonal. In the illustrative example of FIGS. 1-4 the profile is hexagonal.
FIG. 5 depicts a driver 150 useable with the anchor of FIGS. 1-4. The driver 150 includes an elongated body 152 extending between a proximal end 154 and a distal end 156 along an axis 158. The body includes a handle 160 near the proximal end and an anchor engaging shaft 162 near the distal end. The shaft 162 has a profile complementary to the anchor passage 110 profile and is receivable in the anchor passage 110 in axial sliding relationship for transmitting torque to the anchor 100. An axial passage extends longitudinally through the driver 150 between the proximal and distal ends 154, 156. In the illustrative example of FIG. 5, the screw engaging shaft is hexagonal.
FIG. 6 depicts an elongated suture threader 170 extending between a proximal end 172 and a distal end 174 along an axis 176. The threader 170 includes a shaft 178 and a collapsible loop 180 affixed at the distal end of the shaft.
FIG. 7 depicts the anchor 100, driver 150, and threader 170 assembled into an anchor/driver assembly 200 as they would be prepared for surgery. The anchor 100 is coaxially mounted on the driver shaft 162 and the threader 170 is inserted through the axial passage in the driver 150 so that the loop 180 extends out of the driver and anchor past the distal end.
FIG. 8 depicts a suture 202 that is to be attached to a bone 204. The suture 202 extends through a tunnel 206 in the bone 204. The devices and methods shown may be used with any number of sutures. In the illustrative example of FIG. 8, first and second suture limbs 208 and 210 extend from the bone tunnel. The first suture limb 208 is placed through the loop 180 of the threader 170 in preparation for threading the first limb 208 through the anchor/driver assembly 200.
Referring to FIGS. 9 and 10, the threader 170 and first suture limb 208 have been withdrawn through the anchor/driver assembly 200. The anchor/driver assembly 200 is then advanced over the first limb 208 until the anchor 100 engages the opening of the bone tunnel 206. The second limb 210 may be pulled to tension it as desired before the suture anchor 100 is advanced. The anchor 100 is then advanced into the bone tunnel 206 to trap and secure the second limb 210 between the anchor body 102 and tunnel wall 212 in interference manner. The first limb 208 remains unsecured and is able to translate within the axial passage 110 of the anchor 100. The first limb 208 may be pulled to tension it as desired. The first limb may then be secured. For example, the first limb 208 may be knotted, wedged within the anchor passage 110, and/or otherwise secured. The first and second limbs 208 and 210 may be fixed together such as by tying, clamping, adhering, or by other suitable methods so that the limbs 208 and 210 are suspended over the anchor body wall. In the illustrative example of FIG. 10, the suture limbs 208 and 210 have been tied in a knot 214.
FIGS. 11 through 15 illustrate a surgical procedure for tethering two bones 300, 302 together. In the illustrative example of FIGS. 11-15, the method is used to tether two metatarsal bones of a human foot such as, for example, to correct a hallux valgus deformity.
FIG. 11 depicts an optional step of drilling aligned first and second tunnels 304, 306 in the first and second bones 300, 302 in preparation for receiving first and second anchors. The tunnels 304, 306 may be of the same or different diameters. Alternatively, the tunnels may be omitted and the anchors may form their own tunnels in the bone. In the illustrative example of FIG. 11, a stepped drill 308 is used to form aligned tunnels with the first tunnel 304 having a diameter smaller than the second tunnel 306. The drill 308 includes an elongated body extending between a proximal end 310 and a distal end 312 along an axis 314. A first cutting portion 316 at the distal end has a first diameter and a second cutting portion 318 nearer the proximal end has a second diameter larger than the first cutting portion diameter. In the illustrative example of FIG. 11, the stepped drill 308 is advanced through the second bone 302 and into the first bone 300 to form bone tunnels 306, 304. The stepped drill 308 is then withdrawn.
FIGS. 12 and 13 depict the step of installing a first suture anchor 330 into the first bone 300. The first suture anchor 330 has an elongated body 332 extending between a proximal end 334 and a distal end 336 along an axis 338. The first suture anchor 330 includes fixation projections 340 extending radially outwardly from the body. The first suture anchor 330 may be cannulated or non-cannulated. The first suture anchor has a suture 342 attached to it. The suture 342 may have one or more suture limbs extending from the first suture anchor 330 and the suture limbs may be fixed relative to the first suture anchor 330 to permit independent suture tensioning or they may be slidably engaged with the first suture anchor 330 so that tensioning one suture limb tensions the other. In the illustrative example of FIGS. 12-13, the first suture anchor 330 is non-cannulated and has a pointed, self tapping, distal end 336. The suture 342 includes first and second suture limbs 344, 346 fixed relative to the first suture anchor 330 to allow independent tensioning of the suture limbs. A driver 348 couples to the first suture anchor 330 to aid in installing the first suture anchor 330. In the illustrative example of FIGS. 12-13, the first suture anchor 330 is passed through the second bone tunnel 306 and is threaded into the first bone tunnel 304 to secure the first suture anchor 330 in the first bone 300 with the suture 342 extending from the first suture anchor 330 and through the second bone tunnel 306. The first suture anchor 330 may be seated proud of the first bone, flush with the first bone, or recessed within the first bone. In the illustrative example of FIG. 13, the first suture anchor 330 is seated flush.
FIGS. 14 and 15 depict the steps of inserting a second suture anchor 350 into the second bone 302 and securing the suture. The second suture anchor 350 is configured like the suture anchor of FIGS. 1-4. A driver 352 is configured like the driver of FIG. 5. In the illustrative example of FIG. 14, the first limb 344 of the suture is threaded through the second suture anchor 350 and driver 352 as in the example of FIGS. 8-10. The second suture anchor 350 is then advanced over the first limb 344 until the anchor 350 engages the opening of the second bone tunnel 306. The second limb 346 may be pulled to tension it as desired before the suture anchor 350 is advanced. The anchor 350 is then advanced into the bone tunnel 306 to trap and secure the second limb 346 between the anchor body and tunnel wall in interference manner. The second suture anchor 350 may be seated proud of the second bone, flush with the second bone, or recessed within the second bone. In the illustrative example of FIG. 15, the second suture anchor 350 is seated flush. The first limb 344 remains unsecured and is able to translate within the axial passage of the second anchor 350. The first limb 344 may be pulled to tension it as desired. The suture limbs may optionally slidingly engage the first suture anchor such that pulling on the first suture limb 344 tensions both the first and second suture limb. This may be advantageous, for example, to simplify adjusting the relative position of the first and second bone while maintaining equal tension in the first and second suture limbs. The first limb may then be secured. For example, the first limb 344 may be knotted, wedged within the anchor passage, and/or otherwise secured. The first and second limbs 344 and 346 may be fixed together such as by tying, clamping, adhering, or by other suitable methods. In the illustrative example of FIG. 15, the suture limbs 344 and 346 have been tied in a knot 354.
Implants, instruments, and methods have been described to illustrate examples of the present invention. Modifications to the illustrative examples may be made within the scope of the present invention.

## Claims

1. A method of securing first and second suture limbs relative to a bone, the method comprising:
forming a bone tunnel through a portion of a bone, the bone tunnel having a first opening at a first surface of the bone and a second opening at a second surface of the bone;
passing first and second suture limbs through the bone tunnel, the first and second suture limbs exiting together through the first opening;
passing the first suture limb through a longitudinal cannulated of an anchor;
inserting the anchor into the bone tunnel through the first opening to trap the second suture limb between the anchor and bone tunnel in interference relationship, the anchor having an anchor outer side surface and the bone tunnel having a tunnel wall comprised of bone, the outer side surface of the anchor engaging the tunnel wall and the second suture limb being secured between the outer side surface of the anchor and the tunnel wall, wherein the second suture limb does not pass through the longitudinal cannulation; and
securing the first suture limb.

2. The method of claim 1 wherein securing the first suture limb comprises joining it to the second suture limb after inserting the anchor into the bone tunnel.

3. The method of claim 1 further comprising:
passing the first suture limb through a cannulated driver engageable with the cannulated anchor;
then tensioning the first and second suture limbs;
then inserting the bone anchor into the tunnel with the cannulated driver.

4. The method of claim 1 further comprising:
tensioning the second suture limb independently of the suture limb before inserting the anchor into the bone tunnel and tensioning the first suture limb independent of the second suture limb before securing the first suture limb.

5. The method of claim 1 further comprising:
after inserting the anchor into the bone tunnel, pulling the first suture limb to tension both the first and second suture limbs before securing the first suture limb.

6. A method of tethering first and second bones together, the method comprising:
anchoring a first suture anchor to the first bone;
passing first and second suture limbs from the first suture anchor through the second bone by passing the first and second suture limbs through a bone tunnel in the second bone;
passing the first suture limb through a longitudinal cannulation of a second anchor;
inserting the second suture anchor into the bone tunnel in the second bone to secure the second suture limb between the second suture anchor and bone tunnel in interference relationship, the second anchor having an anchor outer side surface and the bone tunnel having a tunnel wall comprised of bone, the outer side surface of the second anchor engaging the tunnel wall and the second suture limb being secured between the outer side surface of the second anchor and the tunnel wall, wherein the second suture limb does not pass through the longitudinal cannulation; and
securing the first suture limb.

7. The method of claim 6 wherein securing the first suture limb comprises joining it to the second suture limb after inserting the second anchor into the bone tunnel.

8. The method of claim 6 wherein the first suture anchor is generally cylindrical and has a maximum diameter along its length and the second suture anchor is generally cylindrical and has a maximum diameter along its length, the second suture anchor maximum diameter being greater than the first suture anchor maximum diameter.

9. The method of claim 6 wherein anchoring a first suture anchor to the first bone comprises passing the first suture anchor and suture through the second bone and into the first bone.

10. The method of claim 6 wherein one of the first and second suture anchors are cannulated and the other is non-cannulated.

11. The method of claim 6 further comprising:
forming aligned second and first tunnels through the second and first bones, the first bone tunnel being of a smaller diameter than the second bone tunnel.

12. The method of claim 11 wherein the tunnels are formed in a single action with a stepped drill.

13. The method of claim 6 wherein the first and second suture ends are fixed to the first suture anchor and are independently tensionable, the method further comprising:
tensioning the second suture limb independent of the first suture limb before inserting the anchor into the bone tunnel and tensioning the first suture limb independent of the second suture limb before securing the first suture limb.

14. The method of claim 6 further comprising:
after inserting the second suture anchor into the second bone tunnel, pulling the first suture limb to tension the first and second suture limbs before securing the first suture limb.

15. The method of claim 14 wherein the first and second suture ends slidingly engage the first suture anchor, such that after the first suture anchor is fully installed, pulling on one of the first and second suture ends causes the other of the first and second suture ends to slide relative to the second suture anchor.

16. The method of claim 6 wherein the bones are metatarsal bones of the human foot.