Facet joint fusion devices and methods

Abstract

A method for promoting fusion of and/or stabilizing a facet joint between two adjacent vertebrae comprises clamping the two adjacent vertebrae across the facet joint to apply a compressive force across the joint. Apparatus for promoting fusion of and/or stabilizing a facet joint comprises at least one cinchable tether and at least one locking member coupled with the tether for locking the cinched tether to maintain compressive force across the facet joint. The tether is adapted to extend through at least one hole through each of two adjacent vertebrae, across the facet joint.

1 . Apparatus for promoting fusion of a facet joint between two adjacent vertebrae, the apparatus comprising:
 at least one cinchable tether adapted to extend through at least one hole through each of two adjacent vertebrae, across the facet joint;   a first bone surface contacting member slidably coupled with the tether for contacting a first of the two vertebrae external to the facet joint;   a second bone surface contacting member coupled with the tether for contacting a second of the two vertebrae external to the facet joint, wherein cinching the tether applies compressive force between the first and second bone surface contacting members across the facet joint; and   at least one locking member coupled with the tether for locking the cinched tether to maintain compressive force across the facet joint.   
     
     
         2 . Apparatus as in  claim 1 , wherein each of the first and second bone surface contacting members each comprise a plate having at least one hole allowing for passage of the tether. 
     
     
         3 . Apparatus as in  claim 1 , further comprising a second cinchable tether, wherein each plate comprises two holes allowing for passage of the two tethers. 
     
     
         4 . Apparatus as in  claim 3 , wherein the plates are curved to conform to surfaces of the two vertebrae. 
     
     
         5 . Apparatus as in  claim 3 , wherein the plates are malleable to conform to surfaces of the two vertebrae. 
     
     
         6 . Apparatus as in  claim 3 , wherein each of the plates comprises:
 a rigid portion; and   a malleable portion for contacting a surface of one of the vertebrae.   
     
     
         7 . Apparatus as in  claim 3 , wherein the plates comprise at least one material selected from the group consisting of titanium, titanium alloys, stainless steel, cobalt-chromium alloy, carbon filled PEEK, ultra-high molecular weight polyethylene, silicone, polyurethane and SEBS-based materials. 
     
     
         8 . Apparatus as in  claim 1 , wherein the apparatus comprises primarily radiolucent materials or including at least one radiopaque marker. 
     
     
         9 . Apparatus as in  claim 1 , further comprising a curved bone contacting member adapted to wrap around surfaces of the two vertebrae adjacent the facet joint, wherein cinching the tether compresses the curved bone contacting member to apply compressive force across the facet joint. 
     
     
         10 . Apparatus as in  claim 1 , wherein the tether is selected from the group consisting of a cord, a cable, a suture, a wire and a T-tag. 
     
     
         11 . Apparatus as in  claim 10 , wherein the tether comprises at least one material selected from the group consisting of stainless steel, titanium, Nitinol, ultra-high molecular weight polyethylene, cobalt-chromium alloy, PTFE, and PET. 
     
     
         12 . Apparatus as in  claim 1 , wherein the at least one locking member comprises at least one crimping member coupled at or near both ends of the tether and slidable along at least one end of the tether. 
     
     
         13 . Apparatus as in  claim 1 , wherein the at least one locking member comprises:
 at least a first locking member coupled with the tether at or near a first end of the tether; and   at least a second locking member coupled with tether at or near a second end of the tether, wherein the first and second locking members lock together.   
     
     
         14 . Apparatus as in  claim 1 , wherein the at least one locking member comprises:
 a lasso member coupled with one end of the tether; and   a rivet slidably coupled with the tether and adapted to engage and lock with the lasso.   
     
     
         15 . A system for promoting fusion of a facet joint between two adjacent vertebrae, the system comprising:
 a facet joint clamping device comprising at least one cinchable tether adapted to extend through at least one hole through each of two adjacent vertebrae, across the facet joint; and   a drill for forming the at least one hole through the two vertebrae.   
     
     
         16 . A system as in  claim 15 , further comprising at least one locking member coupled with the tether for locking the cinched tether to maintain compressive force across the facet joint. 
     
     
         17 . A system as in  claim 15 , further comprising at least one cinching tool for applying force to the cinchable tether. 
     
     
         18 . A system as in  claim 15 , wherein the cinching tool is adapted to apply at least one locking member to the cinchable tether to maintain the force applied to the tether. 
     
     
         19 . A system as in  claim 15 , wherein at least one of the clamping device and the drill are calibrated to form the at least one hole through the vertebrae so as to realign the two vertebrae when the cinchable tether is passed therethrough. 
     
     
         20 . A system as in  claim 15 , further comprising an access device for providing access to the two vertebrae. 
     
     
         21 . A system as in  claim 20 , wherein the access device provides for percutaneous access to the two vertebrae. 
     
     
         22 . A system as in  claim 20 , wherein the access device provides for open surgical access to the two vertebrae. 
     
     
         23 . A system as in  claim 15 , further comprising at least one bone preparation device for preparing one or more bone surfaces within the joint by removing at least one of cartilage or bone. 
     
     
         24 . A system as in  claim 23 , wherein the bone preparation device comprises:
 a flexible cutting guide; and   a cutting device passable over the cutting guide, wherein the guide and the cutting device are adapted to remove cartilage from the bone surfaces while minimizing removal of bone.   
     
     
         25 . A system as in  claim 15 , further comprising at least one fusion promoting material adapted for insertion into the joint to promote fusion of the joint. 
     
     
         26 . A system as in  claim 15 , wherein the clamping device further comprises at least a first bone surface contacting member slidably coupled with the tether for contacting a first of the two vertebrae external to the facet joint. 
     
     
         27 . A system as in  claim 26 , wherein the clamping device further comprises a second bone surface contacting member coupled with the tether for contacting a second of the two vertebrae external to the facet joint, wherein cinching the tether applies compressive force between the first and second bone surface contacting members across the facet joint. 
     
     
         28 . A system as in  claim 27 , wherein each of the first and second bone surface contacting members comprises a plate having at least one hole allowing for passage of the tether. 
     
     
         29 . A system as in  claim 15 , wherein the clamping device further comprises a curved bone contacting member adapted to wrap around surfaces of the two vertebrae adjacent the facet joint, wherein cinching the tether compresses the curved bone contacting member to apply compressive force across the facet joint. 
     
     
         30 . A system as in  claim 15 , wherein the tether is selected from the group consisting of a cord, a cable, a suture, a wire and a T-tag. 
     
     
         31 . A system as in  claim 15 , wherein the tether comprises at least one material selected from the group consisting of stainless steel, cobalt-chromium alloy, titanium, Nitinol, ultra-high molectular weight polyethylene, cobalt-chromium alloy, PTFE, and PET. 
     
     
         32 . A system as in  claim 15 , wherein the at least one locking member comprises at least one crimping member coupled at or near both ends of the tether and slidable along at least one end of the tether. 
     
     
         33 . A system as in  claim 15 , wherein the at least one locking member comprises a T-tag locking member. 
     
     
         34 . A system as in  claim 15 , wherein the at least one locking member comprises:
 at least a first locking member coupled with the tether at or near a first end of the tether; and   at least a second locking member coupled with tether at or near a second end of the tether, wherein the first and second locking members lock together.   
     
     
         35 . A system as in  claim 15 , wherein the at least one locking member comprises:
 a lasso member coupled with one end of the tether; and   a rivet slidably coupled with the tether and adapted to engage and lock with the lasso.