Inflatable intervertebral disc replacement prosthesis

Abstract

An intervertebral disc replacement prosthesis which can be implanted in a collapsed state, then expanded within the disc space such that minimally invasive surgical techniques may be employed for its insertion, and, by virtue of its expandable nature, ligaments can be restored to proper tension, facet joints can be unloaded posteriorly to inhibit degenerative changes, and functional mobility of the intervertebral segment can be restored.

1 . An intervertebral disc replacement prosthesis comprising at least one chamber which can be inflated to conform to various intervertebral spaces.  
     
     
         2 . The prosthesis of  claim 1 , comprising a pair of end plates on opposite sides of said chamber, each having a generally convex surface adapted to engage a respective cranial or caudal surface of neighboring vertebrae.  
     
     
         3 . The prosthesis of  claim 2 , wherein each of said end plates has plural projections or corrugations for engaging said surfaces, to prevent movement of the end plates relative to said surfaces.  
     
     
         4 . The prosthesis of  claim 1 , wherein each of said end plates is rigid.  
     
     
         5 . An intervertebral disc replacement prosthesis comprising a pair of independently inflatable chambers, each adapted to engage a respective cranial or caudal surface of neighboring vertebrae.  
     
     
         6 . The prosthesis of  claim 5 , wherein each of said inflatable chambers has an end plate adapted to engage a respective cranial or caudal surface of neighboring vertebrae.  
     
     
         7 . The prosthesis of  claim 5 , wherein each of said end plates has plural projections or corrugations for engaging said surfaces, to prevent movement of the end plates relative to said surfaces.  
     
     
         8 . The prosthesis of  claim 5 , wherein said chambers have complementary structures which interengage to provide limited universal movement between said chambers.  
     
     
         9 . The prosthesis of  claim 6 , wherein each of said end plates is formed of at least two parts having hinges therebetween so that the prosthesis can be folded prior to insertion through minimally invasive techniques.  
     
     
         10 . The prosthesis of  claim 6 , wherein each of said chambers has a flexible wall.  
     
     
         11 . The prosthesis of  claim 10 , wherein said wall is made of a polymeric material.  
     
     
         12 . The prosthesis of  claim 10 , wherein said wall is made of a fabric.  
     
     
         13 . The prosthesis of  claim 12 , wherein the fabric is Kevlar.  
     
     
         14 . The prosthesis of  claim 12 , wherein the fabric is not substantially stretchable, and the chamber is made is a shape conforming to the space to be filled.