Posterior Spinal Device and Method

Abstract

An intervertebral joint assembly includes an upper support and a lower support, each of which has two or more components. The upper and lower support components are arranged in situ to form the upper and lower supports, respectively. By arranging the supports in situ, the supports can be introduced from the back of the patient, for example with an arthroscope. Each of the upper and lower supports has a surface adapted to engage a vertebra and a surface adapted to engage the other support or an intermediate member to form an articulate joint which articulates the joint assembly. In some embodiments, the components of the upper and lower supports are assembled in situ, for example with pivoting, telescoping or bending, to form the upper and lower supports, respectively. The supports can be attached to vertebrae with pedicles screws, and/or other anchors attached to the supports.

1 . An intervertebral joint assembly comprising:
 an upper support having a lower surface and comprising two or more components, wherein said upper support components may be arranged in situ to form the upper support; and   a lower support having an upper surface and comprising two or more components wherein said lower support components may be arranged in situ to form the lower support; and   wherein the upper support the upper and lower surfaces are adapted to engaged each other or an intermediate member to form an articulate joint.   
     
     
         2 . The assembly of  claim 1  wherein each of the two or more components of the upper support comprises an upper flat surface to engage an upper vertebra along an upper vertebral engagement surface, and the upper flat surfaces are positioned along the upper vertebral engagement surface while the upper components are arranged to form the upper support. 
     
     
         3 . The assembly of  claim 2  wherein each of the two or more components of the lower support comprises a lower flat surface to engage a lower vertebra along a lower vertebra engagement surface, and the lower flat surfaces are positioned along the lower vertebra engagement surface while the lower components are arranged to form the lower support. 
     
     
         4 . The assembly of  claim 1  wherein at least one component of the upper support comprises at least one structure adapted to anchor the support in an upper vertebra, and/or at least one component of the lower support comprises at least one structure adapted to anchor the support in a lower vertebra. 
     
     
         5 . The assembly of  claim 4  wherein the anchor structure(s) comprise holes adapted to receive anchoring screws. 
     
     
         6 . The assembly of  claim 4  wherein the anchor structure(s) comprise protrusions adapted to engage vertebra when the assembly is inserted into an intervertebral location. 
     
     
         7 . The assembly of  claim 4  wherein the anchor structure(s) comprise an elongate anchor adapted to enter a grove formed in a vertebra while the assembly is inserted into an intervertebral location. 
     
     
         8 . The assembly of  claim 4  wherein at least two components of the upper support comprise one or more of structures adapted to anchor the upper support in the upper vertebrae and/or at least two components of the lower support comprise one or more structures adapted to anchor the lower support in the lower vertebrae. 
     
     
         9 . The assembly of  claim 1  wherein each support comprises three or more components, each component having a first end and a second end which mechanically couple the components arranged to form the supports. 
     
     
         10 . The assembly of  claim 9  wherein the components are coupled at locations on each support to define a bounded area on the support, and wherein the articulation surfaces are located at least partially within the bounded areas. 
     
     
         11 . The assembly of  claim 1  wherein the components of one or more supports are adapted to assemble in situ to form the support at a surgical site. 
     
     
         12 . The assembly of  claim 11  wherein the components are adapted to assemble in situ from a first elongate arrangement for introduction to a surgical site to a second folded arrangement to form the support at the surgical site. 
     
     
         13 . The assembly of  claim 11  wherein the components of both supports are adapted to assemble in situ to form the supports. 
     
     
         14 . The assembly of  claim 11  wherein adapted to assemble comprises at least one of adapted to pivot, or adapted to telescope, or adapted to bend. 
     
     
         15 . The assembly of  claim 11  wherein one or more supports comprise three components. 
     
     
         16 . The assembly of  claim 15  wherein the three components comprises a distal component, a middle component and a proximal component. 
     
     
         17 . The assembly of  claim 16  wherein the middle component extends between the proximal and distal components. 
     
     
         18 . The assembly of  claim 16  wherein at least one of the three components comprises an elongate anchor adapted to enter a groove formed in a vertebra. 
     
     
         19 . An intervertebral joint assembly as in  claim 1 , wherein the lower surface of the upper support comprises a convex or concave feature and the upper surface of the lower support comprises a concave or convex feature which mates the feature on the upper support. 
     
     
         20 . An intervertebral joint assembly as in  claim 1 , wherein the intermediate member comprises first and second curved surfaces, the first and second surfaces engaging the upper and lower supports, respectively.