System and method for securing tissue to bone

Abstract

Disclosed herein are methods and devices for securing soft tissue to a rigid material such as bone. A tissue anchoring device is described that comprises an anchor body and a spreader such that tissue may be captured or compressed between outside surfaces on the anchor and inside surfaces of a bone tunnel to secure the tissue within the tunnel. Methods are described that enable use of the bone anchoring device to secure a tissue graft into the tibial and femoral bones during anterior cruciate ligament (“ACL”) reconstruction.

What is claimed is: 
     
         1 . An expandable bone anchor, comprising:
 an anchor body comprising:
 a distal tapered anchor tip; and 
 a plurality of rigid side portions extending proximally from the anchor tip, each side portion coupled to the anchor tip through a double hinge; and 
   a spreader configured to advance distally into the anchor body, thereby causing the rigid side portions to expand outward.   
     
     
         2 . The anchor of  claim 1  wherein the spreader is coupled to the side portions. 
     
     
         3 . The anchor of  claim 1 , wherein the spreader is slidably coupled to the side portions. 
     
     
         4 . The anchor of  claim 3 , wherein the spreader comprises a plurality of longitudinal tracks and each side portion is coupled to one of the tracks such that the side portions can slide longitudinally along the tracks. 
     
     
         5 . The anchor of  claim 1 , wherein the spreader comprises at least a portion that is tapered distally. 
     
     
         6 . The anchor of  claim 1 , wherein the anchor tip comprises a proximal locking member and the spreader comprises a distal locking member, wherein the two locking members are configured to lock together upon maximal distal advancement of the spreader. 
     
     
         7 . The anchor of  claim 6 , wherein the proximal locking member on the tip comprises a post having an outwardly protruding ridge and the distal locking member on the spreader comprises a hollow cylinder configured to receive the post. 
     
     
         8 . The anchor of  claim 7 , wherein the hollow cylinder comprises a groove on an inside surface configured to receive the protruding ridge. 
     
     
         9 . The anchor of  claim 7 , wherein the hollow cylinder comprises expandable tabs. 
     
     
         10 . The anchor of  claim 1 , wherein upon maximal expansion, the rigid side portions are expanded to a substantially uniform extent along their length.