Suture anchor with improved torsional drive head

Abstract

The present invention provides a suture anchor that includes an elongate shank defining a longitudinal axis and having at least one engaging member for applying the suture anchor within the bone and securing the suture anchor in the bone once implanted formed thereon, and a drive head having a proximal end, a distal end and a radial cross-sectional geometry, where the drive head is mated to the elongate shank, includes at least one suture attachment element formed in a portion thereof and at least one anti-rotational member integral therewith, suture anchor kits utilizing the suture anchors and methods of attaching bone to gone.

What is claimed is: 
     
         1 . A method for attaching soft tissue to bone, comprising the steps of:
 forming a bone cavity within a bony structure;   providing a suture anchor comprising an elongate shank comprising a proximal end and a distal end and defining a longitudinal axis, said shank further comprising at least one engaging member formed thereon; and a drive head comprising a proximal end, a distal end mated to said elongate shank, at least one suture attachment element formed in a portion of said drive head, said suture attachment element comprising a suture disposed therein, and at least one anti-rotational member integral therewith;   inserting said suture anchor into said bone cavity; and   attaching soft tissue to said suture.   
     
     
         2 . The method of  claim 1  wherein said radial cross-sectional geometry of said drive head is rectangular, square, hexagonal, flattened oval or oval. 
     
     
         3 . The method of  claim 2  wherein said radial cross-sectional geometry of said drive head is oval. 
     
     
         3 . The method of  claim 1  wherein said suture attachment element comprises at least one suture tunnel extending transversely through said drive head. 
     
     
         4 . The method of  claim 3  wherein said drive head further comprises at least one suture-receiving channel formed in an outer surface of said drive head and originating at and extending proximally from an opening of said suture tunnel. 
     
     
         5 . The method of  claim 2  wherein a suture is disposed in said suture attachment element. 
     
     
         6 . The suture anchor of  claim 1  wherein said at least one engaging member comprises a helical thread. 
     
     
         7 . The suture anchor of  claim 1  wherein said anti-rotational member is tapered proximally along the length of the drive head. 
     
     
         8 . The suture anchor of  claim 1  wherein said longitudinal cross-sectional geometry of said anti-rotational member is rectangular, curved, parabolic, or triangular. 
     
     
         9 . The suture anchor of  claim 1  wherein said elongate shank tapers from said proximal end to said distal end. 
     
     
         10 . The suture anchor of  claim 1  wherein said suture anchor comprises a biodegradable material. 
     
     
         11 . The suture anchor of  claim 10  wherein said biodegradable material is a polymer, copolymer, or polymer blend formed from monomers selected from the group consisting of lactic acid, lactide, glycolic acid, glycolide, epsilon-caprolactone, 1,4-dioxan-2-one and 1,3-dioxan-2-one. 
     
     
         12 . The suture anchor of  claim 10  wherein said biodegradable material is selected from the group consisting of biodegradable glass, mono-calcium phosphate, dicalcium phosphate, tricalcium phosphate, alpha-tricalcium phosphate, beta-tricalcium phosphate, tetracalcium phosphate, hydroxyapatite, calcium sulfate, calcium oxide, calcium carbonate, magnesium calcium phosphate, phospate glass and bioglass. 
     
     
         13 . The suture anchor of  claim 10  wherein said biodegradable material is a composite comprised of beta-tricalcium phosphate and poly(lactide). 
     
     
         14 . The suture anchor of  claim 10  wherein said biodegradable material is a composite comprised of 30 weight percent beta-tricalcium phosphate particles in 70 weight percent poly(lactide)/poly(glycolide) copolymer, wherein the mole ratio of lactide to glycolyde is 85/15.