Prostheses, tools and methods for replacement of natural facet joints with artificial facet joint surfaces

Abstract

Cephalad and caudal vertebral facet joint prostheses and methods of use are provided. The cephalad prostheses are adapted and configured to be attached to a lamina portion of a vertebra without blocking a pedicle portion of the cephalad vertebra.

1 . A system for conducting surgery on a spine of a patient, the system comprising: a frame comprising: a first anchoring feature attachable to a first bone portion of the patient; a second anchoring feature attachable to a second bone portion of the patient, wherein the first and second bone portions are spaced apart from each other; a first registration feature shaped to guide at least one surgical instrument; and a bridging structure configured to couple the first and second anchoring features and the first registration feature together such that the second anchoring feature is positionable at any of a variety of positions with respect to the first anchoring feature, wherein the first and second anchoring features are configured to be attached to pedicles of the spine.  
     
     
         2 . The system of  claim 1 , wherein the frame further comprises an external anchoring feature attachable to a stationary external support to stabilize the frame.  
     
     
         3 . The system of  claim 1 , wherein the frame further comprises a second registration feature, wherein the first and second registration features cooperate to enable performance of two distinct functions substantially symmetrically across a sagittal plane of the patient.  
     
     
         4 . The system of  claim 3 , wherein the first and second anchoring features are configured to be attached to the spine, on either side of the sagittal plane.  
     
     
         5 . The system of  claim 1 , further comprising at least one prosthesis shaped to replace at least a portion of a facet of a vertebra of the spine.  
     
     
         6 . The system of  claim 1 , further comprising: at least two prostheses shaped to replace two facets of a vertebra of the spine; and a cross-linking member attachable to the prostheses to couple the prostheses together.