Self-locking suture anchor

Abstract

A tissue anchor having a length of filament held so that an applied force greater than a threshold force will cause the filament to move longitudinally, while an applied force less than the threshold force will not move the filament, and methods of attaching soft tissue to bone using such an anchor.

1 . A method for anchoring a suture, comprising:
 implanting an anchor member in bone, the anchor member having a cavity extending therethrough with opposite open ends;   moving a deployment shaft to position insertion element in the cavity in the anchor member, the insertion element and the anchor member engaging a suture extending through the cavity to lock a loop of suture extending from the cavity in a fixed position; and   frangibly detaching the deployment shaft from the insertion element.   
   
   
       2 . The method of  claim 1 , wherein the suture is held between the anchor member and the insertion element by a compression fit. 
   
   
       3 . The method of  claim 1 , wherein moving the deployment shaft comprising pulling the deployment shaft to pull the insertion element into the cavity. 
   
   
       4 . The method of  claim 1 , wherein frangibly detaching the deployment shaft from the insertion element comprises applying tension to a frangible portion formed between the deployment shaft and the insertion element. 
   
   
       5 . A method for anchoring tissue to bone, comprising:
 implanting an anchor member in a bone tunnel;   applying tension to a deployment shaft attached to an insertion element to pull the insertion element into a cavity formed in the anchor member;   applying tension to a frangible portion formed between the deployment shaft and the insertion element to cause the frangible portion to shear to separate the deployment shaft from the insertion element.   
   
   
       6 . The method of  claim 5 , wherein the insertion element is held within the cavity of the anchor member by an interference fit. 
   
   
       7 . The method of  claim 5 , wherein the anchor member includes a suture extending therethrough, and wherein the suture is engaged between the anchor member and the insertion element. 
   
   
       8 . The method of  claim 7 , wherein the suture extends through the cavity, forms a loop segment, and extends back through the cavity. 
   
   
       9 . A method for anchoring tissue to bone, comprising:
 implanting an anchor element in a bone tunnel, the anchor element having a suture passing through a cavity in the anchor element, forming a loop segment, and passing back through the cavity in the anchor element; and   inserting an insertion element into the cavity in the anchor element to hold the suture therein by interference fit.   
   
   
       10 . The method of  claim 9 , wherein the insertion element is inserted into the cavity in the anchor member using a deployment device. 
   
   
       11 . The method of  claim 10 , wherein the deployment device is attached to the insertion element during deployment, and wherein the deployment device is frangibly sheared from the insertion element after deployment of the insertion element into the anchor member. 
   
   
       12 . The method of  claim 10 , wherein the deployment device is pulled to pull the insertion element into the cavity in the anchor member.