Intervertebral disc prosthesis

Abstract

A flexible prosthetic cover ( 12 ) shaped to form a replacement nucleus pulposis for an intervetebral disc comprises an aperture for the introduction of filling material therein, and an elongate introducer member ( 28 ) configured to pass into the aperture. The cover has a strengthened portion ( 26 ) substantially opposite the aperture for engaging the distal end ( 42 ) of the member, the strenghtened portion and the said distal end being arranged to interlock, for facilitating orientation of the cove, for example so as to prevent relative rotation there between.

1 . A flexible prosthetic cover shaped to form a replacement nucleus pulposis for an intervertebral disc and comprising an aperture for the introduction of filling material therein, and an elongate introducer member configured to pass into the aperture, the cover having a strengthened portion substantially opposite the aperture for engaging the distal end of the member, the strengthened portion and the said distal end being arranged to interlock, for facilitating orientation of the cover.  
   
   
       2 . The flexible prosthetic cover of  claim 1  wherein the strengthened portion and the distal end interlock so as to prevent relative rotation there between.  
   
   
       3 . The flexible prosthetic cover of  claim 1 , wherein the aperture comprises an internal flap valve.  
   
   
       4 . The flexible prosthetic cover of  claim 1  wherein the strengthened portion comprises a radio opaque marker for indicating the orientation of the strengthened portion.  
   
   
       5 . The flexible prosthetic cover of  claim 1  wherein the introducer member has an internal channel communicating with an aperture at or adjacent the distal end therefore for allowing the injection of filling material into the cover.  
   
   
       6 . The flexible prosthetic cover of  claim 1  wherein the aperture is arranged to accept an introducer tube shaped to pass over the introducer member and to form a channel there between after removal of the introducer member for allowing the injection of filling material into the cover.  
   
   
       7 . The flexible prosthetic cover of  claim 1  further comprising a deformable porous body or mesh or coil shaped to fit within the cover.  
   
   
       8 . The flexible prosthetic cover of  claim 1  further comprising an edge portion being a resiliently deformable annular sleeve shaped to fit within a disc annulus, the aperture and the strengthened portion being provided in the edge portion.  
   
   
       9 . The flexible prosthetic cover of  claim 8  further comprising a pair of opposed flexible central portions each joining an edge of the sleeve.  
   
   
       10 . The flexible prosthetic cover of  claim 9 , wherein the central portions are arranged, when the cover is filled with a filling material, to allow filling material to pass there  20  through.  
   
   
       11 . The flexible prosthetic cover of  claim 9  wherein the central portions are formed of a material arranged to break under filling pressure.  
   
   
       12 . The flexible prosthetic cover of  claim 9  wherein the central portions are formed of a material which is absorbable by the body.  
   
   
       13 . The flexible prosthetic cover of  claim 1  wherein the strengthened portion comprises a shaped recess or protrusion, and the distal end of the introducer rod is correspondingly shaped to interlock therewith.  
   
   
       14 . The flexible prosthetic cover of  claim 1  wherein the aperture comprises a valve structure formed of an imaging transparent material.  
   
   
       15 . The flexible prosthetic cover of  claim 1  further comprising obturating means operatively associated with the aperture.  
   
   
       16 . A prosthetic cover for an intervertebral disc comprising an edge portion being a resiliently deformable annular sleeve shaped to fit within a disc annulus, and a pair of opposed flexible central portions each joining an edge of the sleeve, the edge portion including an aperture for the introduction of a filling material.  
   
   
       17 . The flexible prosthetic cover of  claim 16  further comprising a flexible balloon catheter shaped to fit within the cover when inflated, and arranged to fit through the aperture when deflated.