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. The invention also provides systems for treating spinal pathologies that include intervertebral discs in combination with spinal and facet joint prostheses.

1 . A system for treating spinal pathologies including an intervertebral disc prosthesis in combination with an adaptable facet joint prosthesis comprising: a crossbar having a first end and a second end; a pair of cephalad prosthesis elements each having a bone engaging end and an end adapted to couple to the crossbar; and a pair of caudal prosthesis elements each having a surface adapted to receive a crossbar end and a fixation element. 
     
     
         2 . The adaptable spinal facet joint prosthesis according to  claim 1  wherein the distance between the crossbar first end and second end is adjustable. 
     
     
         3 . The adaptable spinal facet joint prosthesis according to  claim 1  wherein the crossbar first end and second end have a round surface to engage with the caudal prosthesis surface adapted to receive a crossbar end. 
     
     
         4 . The adaptable spinal facet joint prosthesis according to  claim 1  wherein the bone engaging end of at least one of the pair of cephalad prosthesis elements is disengageably coupled to the at least one of the pair of cephalad prosthesis elements. 
     
     
         5 . The adaptable spinal facet joint prosthesis according to  claim 4  wherein the bone engaging end is adapted to receive one of a plurality of bone engaging ends each one of said plurality of bone engaging ends having a different length. 
     
     
         6 . The adaptable spinal facet joint prosthesis according to  claim 1  wherein at least one of the pair of cephalad prosthesis elements or at least one of the pair of caudal prosthesis elements comprises an anti-rotation feature. 
     
     
         7 . The adaptable spinal facet joint prosthesis according to  claim 1  further comprising a crossbar mount having a crossbar engaging portion and a cephalad prosthesis element engaging portion. 
     
     
         8 . The adaptable spinal facet joint prosthesis according to  claim 7  wherein the crossbar passes through the crossbar engaging portion. 
     
     
         9 . The adaptable spinal facet joint prosthesis according to  claim 7  wherein the crossbar is attached to the crossbar engaging portion. 
     
     
         10 . The adaptable spinal facet joint prosthesis according to  claim 7  wherein when the crossbar is connected to the crossbar engaging portion, the crossbar mount may be rotated about the crossbar. 
     
     
         11 . A system for treating spinal pathologies including an intervertebral disc prosthesis in combination with an adaptable facet joint prosthesis comprising: a first cephalad prosthesis element and a second cephalad prosthesis element; a first caudal prosthesis and a second caudal prosthesis; and a crossbar element connected to the first and second cephalad prosthesis elements, the crossbar element having a first end in contact with the first caudal prosthesis and a second end in contact with the second caudal prosthesis wherein at least one of the first cephalad prosthesis element, the second cephalad prosthesis element, the caudal prosthesis, the second caudal prosthesis, and the crossbar element having a configurable portion. 
     
     
         12 . The spinal prosthesis according to  claim 11  wherein the configurable portion is part of the first cephalad prosthesis element or the second cephalad prosthesis element. 
     
     
         13 . The spinal prosthesis according to  claim 12  wherein the configurable portion is the height of the first or the second cephalad prosthesis element relative to the crossbar element. 
     
     
         14 . The spinal prosthesis according to  claim 12  wherein the configurable portion is the angle formed between the first cephalad prosthesis element and the crossbar element or the angle formed between the second cephalad prosthesis element and the crossbar element. 
     
     
         15 . The spinal prosthesis according to  claim 12  wherein the configurable portion is the angle formed between an axial plane passing through the crossbar element and either the first cephalad prosthesis element or the second cephalad prosthesis element. 
     
     
         16 . The spinal prosthesis according to  claim 15  wherein the angle formed between the first cephalad prosthesis element and an axial plane passing through the crossbar element is the same as the angle formed between the second cephalad prosthesis element and an axial plane passing through the crossbar element. 
     
     
         17 . The spinal prosthesis according to  claim 12  wherein the first and second cephalad prosthesis element comprises an arm, an elbow and a stem wherein the arm has a crossbar engaging end and is attached to the elbow and the stem has a distal tip and is attached to the elbow and the shape of the elbow defines an arm-stem angle. 
     
     
         18 . The spinal prosthesis according to  claim 17  wherein the shape of the elbow defines an arm-stem angle of 90°. 
     
     
         19 . The spinal prosthesis according to  claim 11  wherein the configurable portion is part of the first caudal prosthesis element or the second caudal prosthesis element. 
     
     
         20 . The spinal prosthesis according to  claim 19  wherein the configurable portion is an angle formed between the crossbar element first end and the first caudal prosthesis. 
     
     
         21 . The spinal prosthesis according to  claim 20  wherein the configurable portion is an angle formed between the crossbar element second end and the second caudal prosthesis.