Bioabsorbable interference screw for endosteal fixation of ligaments

Abstract

A bioabsorbable interference screw which, upon insertion, the screw engages cortical bone at the back end of the bone tunnel and fills all but 5-10 mm. of the tunnel, thereby providing increased fixation strength while also promoting fast healing. The screw includes a head provided with a specially designed drive socket with radially extending slots at its outer end for receiving corresponding protrusions on the shaft of screwdriver. The drive socket optimizes the torque capacity of the screw.

1 . A bioabsorbable interference screw for ACL reconstruction, comprising: 
 an elongated threaded bioabsorbable body having a proximal end, a distal end, and a length of 35 mm for substantially longitudinally filling a tibial tunnel, the threads of the elongated threaded bioabsorbable body extending along substantially the entire length of the elongated threaded body, the screw having a width dimensioned to provide an interference fit in the tibial tunnel;    a tip disposed at the distal end of the elongated body, the tip having a taper to facilitate insertion of the screw into the tibial tunnel; and    a drive socket disposed within the screw and extending from the proximal end of the elongated threaded body, wherein the drive socket includes a plurality of radially extending slots configured to receive corresponding radially extending protrusions on a shaft of a screwdriver.    
   
   
       2 . The bioabsorbable interference screw of  claim 1 , wherein the screw is fully cannulated for receiving a guide pin.  
   
   
       3 . The bioabsorbable interference screw of  claim 1 , wherein the screw has a diameter of 9 mm. at the drive socket.  
   
   
       4 . The bioabsorbable interference screw of  claim 1 , wherein the screw has a diameter of 10 mm. at the drive socket.  
   
   
       5 . The bioabsorbable interference screw of  claim 1 , wherein the screw has a diameter of 11 mm. at the drive socket.  
   
   
       6 . The bioabsorbable interference screw of  claim 1 , wherein the screw has a diameter of 12 mm. at the drive socket.