Facet joint prosthesis

Abstract

A facet joint prosthesis comprising an inferior prosthetic portion and a superior prosthetic portion is disclosed. Inferior prosthetic portion includes a first anchor member and a first articulating member and superior prosthetic portion includes a second anchor member and a second articulating member. The first articulating member comprises a support portion and first articulating surface and the second articulating member comprises a second articulating surface, and first and second articulating surfaces are configured and dimensioned to contact or engage one another. A flexible element is positioned between the support portion and the first articulating surface.

What is claimed is: 
     
         1 . A spinal implant comprising:
 a first support member;   an inferior prosthetic segment attached to the first support member;   a second support member; and   a superior prosthetic segment attached to the second support member;   wherein the inferior prosthetic segment and the superior prosthetic segment are configured to articulate relative to one another.   
     
     
         2 . The implant of  claim 1 , wherein the inferior prosthetic segment comprises a planar, plate-like member. 
     
     
         3 . The implant of  claim 2 , wherein the superior prosthetic segment comprises a cup-feature for receiving the planar, plate-like inferior prosthetic segment. 
     
     
         4 . The implant of  claim 3 , wherein the cup-feature comprises a rectangular socket. 
     
     
         5 . The implant of  claim 1 , wherein the superior prosthetic segment comprises one or more ramped surfaces that extend from a socket-like structure. 
     
     
         6 . The implant of  claim 1 , wherein the superior prosthetic segment comprises a partial rectangular cup or socket-like structure. 
     
     
         7 . The implant of  claim 1 , wherein the inferior prosthetic segment and the superior prosthetic segment are made of titanium. 
     
     
         8 . The implant of  claim 1 , wherein the inferior prosthetic segment comprises a hook member. 
     
     
         9 . The implant of  claim 8 , wherein the superior prosthetic segment comprises a receiver member or head for receiving the hook member. 
     
     
         10 . The implant of  claim 9 , wherein the hook member comprises a gusset that is received into a cut-out formed in the receiver member. 
     
     
         11 . A spinal implant comprising:
 a first support member;   a first inferior prosthetic segment attached to the first support member;   a second inferior prosthetic segment attached to the first support member;   a second support member;   a first superior prosthetic segment attached to the second support member; and   a second superior prosthetic segment attached to the second support member;   wherein the inferior prosthetic segment and the superior prosthetic segment are configured to articulate relative to one another.   
     
     
         12 . The implant of  claim 11 , wherein the first inferior prosthetic segment comprises a planar, plate-like member. 
     
     
         13 . The implant of  claim 12 , wherein the first superior prosthetic segment comprises a cup-feature for receiving the planar, plate-like first inferior prosthetic segment. 
     
     
         14 . The implant of  claim 13 , wherein the cup-feature comprises a rectangular socket. 
     
     
         15 . The implant of  claim 11 , wherein the first superior prosthetic segment comprises one or more ramped surfaces that extend from a socket-like structure. 
     
     
         16 . The implant of  claim 11 , wherein the first superior prosthetic segment comprises a partial rectangular cup or socket-like structure. 
     
     
         17 . The implant of  claim 11 , wherein the first inferior prosthetic segment and the first superior prosthetic segment are made of titanium. 
     
     
         18 . The implant of  claim 11 , wherein the first inferior prosthetic segment comprises a hook member. 
     
     
         19 . The implant of  claim 18 , wherein the first superior prosthetic segment comprises a receiver member or head for receiving the hook member. 
     
     
         20 . The implant of  claim 19 , wherein the hook member comprises a gusset that is received into a cut-out formed in the receiver member.