Intervertebral prosthesis

Abstract

Intervertebral prosthesis ( 10 ) with at least one cover plate ( 11 ) which bears on a vertebral body ( 1 ) and is to be firmly connected thereto. In order to ensure that the prosthesis ( 10 ), during its insertion or during its lifetime, does not contribute to a protruding bone margin ( 5 ) breaking off, the cover plate ( 11 ) is provided with a bulge ( 12 ) corresponding to the depression ( 4 ) and/or with a bevel, a shortened end or rounded end ( 13 ).

1 . Intervertebral prosthesis with at least one cover plate ( 11 ,  19 ) which bears on a vertebral body ( 1 ,  2 ) and is to be connected thereto, characterized in that the cover plate surface directed toward the vertebral body ( 1 ) has a bulge ( 12 ) protruding beyond the level of adaptation to the normal shape of the vertebral body.  
     
     
         2 . Intervertebral prosthesis according to  claim 1 , characterized in that the bulge ( 12 ) has a smaller extent than the cover plate surface.  
     
     
         3 . Intervertebral prosthesis according to  claim 2 , characterized in that the bulge ( 12 ) lies nearer to the dorsal margin ( 13 ) of the cover plate surface than to its ventral margin.  
     
     
         4 . Intervertebral prosthesis according to  claim 3 , characterized in that the bulge ( 12 ) reaches as far as the dorsal edge ( 13 ) of the cover plate surface.  
     
     
         5 . Intervertebral prosthesis in particular according to  claim 4 , with at least one cover plate ( 11 ,  14 ) which bears on a vertebral body ( 1 ) and is to be connected thereto, characterized in that a bevel or rounding ( 13 ,  16 ) is provided at the margin of the cover plate surface directed toward the vertebral body ( 1 ).  
     
     
         6 . Intervertebral prosthesis according to  claim 5 , characterized in that the bevel or rounding ( 13 ,  16 ) is provided at least on the dorsal side.  
     
     
         7 . Intervertebral prosthesis according to  claim 5  or  6 , characterized in that the bevel or rounding ( 13 ,  16 ) extends over at least 5% of the dimension of the cover plate surface in the A-P direction.  
     
     
         8 . Intervertebral prosthesis according to one of  claims 5  to  7 , characterized in that the bevel or rounding ( 13 ) is part of a bulge ( 12 ) according to  claim 4 .  
     
     
         9 . Intervertebral prosthesis in particular according to one of  claims 1  to  8 , with at least one cover plate ( 14 ) which bears on a vertebral body ( 1 ) and is to be connected thereto and which has teeth ( 17 ) intended to penetrate into the vertebral body ( 1 ), characterized in that the distance of the teeth ( 17 ) from the dorsal edge of the cover plate ( 14 ) is at least 20% of the cover plate size in the A-P direction.  
     
     
         10 . Intervertebral prosthesis according to  claim 9 , characterized in that at least one of the teeth ( 17 ) arranged near the dorsal edge and designed to be self-cutting extends substantially in a sagittal direction.  
     
     
         11 . Intervertebral prosthesis according to  claim 9 , characterized in that at least one of the teeth arranged near the dorsal edge has a lower height than teeth arranged further in the ventral direction.  
     
     
         12 . Intervertebral prosthesis according to one of  claims 1  to  11 , characterized in that the bulge ( 12 ) or bevel or rounding ( 13 ,  16 ) is formed by a separate attachment part ( 20 ) connected, or to be connected, to the cover plate ( 19 ).  
     
     
         13 . Intervertebral prosthesis according to  claim 12 , characterized in that a plurality of different attachment parts ( 20 ) are provided, and a small number of different cover plates ( 19 ) which can be connected to them.  
     
     
         14 . Set of intervertebral prostheses which comprise at least one cover plate ( 11 ,  19 ), with a substantially flat cover plate surface, which bears on a vertebral body ( 1 ) and is to be connected thereto, characterized in that it comprises at least one intervertebral prosthesis whose cover plate surface has a bulge ( 20 ).  
     
     
         15 . Set of intervertebral prostheses which comprise at least one cover plate ( 11 ,  19 ) which has a dorsal margin and which bears on a vertebral body ( 1 ) and is to be connected thereto, characterized in that it comprises at least one intervertebral prosthesis on whose cover plate the dorsal margin is shortened.