Crossbar Spinal Prosthesis Having a Modular Design and Systems For Treating Spinal Pathologies

Abstract

An adaptable spinal facet joint prosthesis, including a pedicle fixation element; a laminar fixation element; and a facet joint bearing surface having a location adaptable with respect at least one of the pedicle fixation element and the laminar fixation element. The invention also includes a method of implanting an adaptable spinal facet joint prosthesis including the steps of determining a desired position for a facet joint bearing surface; and attaching a prosthesis comprising a facet joint bearing surface to a pedicle portion of a vertebra and a lamina portion of a vertebra to place the facet joint bearing surface in the desired position. The invention also provides a facet joint prosthesis implant tool including a tool guide adapted to guide a vertebra cutting tool; and first and second fixation hole alignment elements extending from the saw guide.

1 . An implant comprising:
 a cephalad prosthesis; and   a caudal prosthesis, wherein the caudal prosthesis is operably attached to the cephalad prosthesis, wherein the cephalad prosthesis comprises a fixation stem element including a proximal end and a distal end, wherein the distal end comprises a paddle portion having a wider width than the proximal end.   
     
     
         2 . The implant of  claim 1 , wherein the fixation stem comprises surface projections between the proximal end and the distal end. 
     
     
         3 . The implant of  claim 1 , wherein the fixation stem comprises pits between the proximal end and the distal end. 
     
     
         4 . The implant of  claim 1 , wherein the paddle has a flat, rounded profile. 
     
     
         5 . The implant of  claim 1 , wherein the fixation stem comprises a set of proximal grooves separated from a set of distal grooves by a non-grooved portion. 
     
     
         6 . The implant of  claim 1 , wherein the non-grooved portion comprises a reduced diameter portion relative to adjacent portions of the fixation stem. 
     
     
         7 . The implant of  claim 1 , wherein the paddle portion comprises a tapered width. 
     
     
         8 . An implant comprising:
 a cephalad prosthesis, wherein the cephalad prosthesis comprises a fixation stem element including a proximal end and a distal end, wherein the distal end comprises a paddle portion having a wider width than the proximal end; and   a caudal prosthesis operably attached to the cephalad prosthesis.   
     
     
         9 . The implant of  claim 8 , wherein the fixation stem comprises a plurality of anti-rotation sections. 
     
     
         10 . The implant of  claim 9 , wherein the anti-rotation sections comprise a plurality of ridges that extend along a length of the fixation stem. 
     
     
         11 . The implant of  claim 8 , wherein the fixation stem is bent at an angle between the proximal end and the distal end. 
     
     
         12 . The implant of  claim 8 , wherein the fixation stem comprises helical longitudinal depressions. 
     
     
         13 . The implant of  claim 8 , wherein the paddle has a flat, rounded profile. 
     
     
         14 . An implant comprising:
 a pair of cephalad prosthesis; and   a pair of caudal prosthesis operably attached to the pair of cephalad prosthesis, wherein the pair of caudal prosthesis are each attached to a crossbar,   wherein the pair of cephalad prosthesis and/or the pair of caudal prosthesis includes a fixation stem including a proximal end and a distal end, wherein the distal end comprises a paddle portion having a wider width than the proximal end.   
     
     
         15 . The implant of  claim 14 , wherein the fixation stem comprises surface projections between the proximal end and the distal end. 
     
     
         16 . The implant of  claim 14 , wherein the fixation stem comprises pits between the proximal end and the distal end. 
     
     
         17 . The implant of  claim 14 , wherein the paddle has a flat, rounded profile. 
     
     
         18 . The implant of  claim 14 , wherein the fixation stem comprises a set of proximal grooves separated from a set of distal grooves by a non-grooved portion. 
     
     
         19 . The implant of  claim 14 , wherein the fixation stem comprises a set of proximal grooves separated from a set of distal grooves by a non-grooved portion. 
     
     
         20 . The implant of  claim 14 , wherein the non-grooved portion comprises a reduced diameter portion relative to adjacent portions of the fixation stem.