Spinal implant and cutting tool preparation accessory for mounting the implant

Abstract

A spinal cage implant is adapted to be inserted in a damaged intervertebral disc for restoring the discal height and permitting an arthoesis. The implant comprises a central part with walls and terminal parts for bearing against the cortical bone of the vertebral end plates. The implant bears against the vertebral end plates with terminal parts and contains bone graft material between walls with an opening to permit bone fusion between the two vertebrae. The implant permits restoring the physiological lordosis and the intervertebral height.

1 - 30 . (canceled) 
   
   
       31 . An implant for insertion between a first vertebra and a second vertebra, comprising an elongated body extending along a longitudinal axis, said body including:
 a first terminal part on said longitudinal axis defining a first bearing surface to bear against the first vertebra and a second bearing surface opposite said first bearing surface to bear against the second vertebra;   a second terminal part on said longitudinal axis opposite said first terminal part, said second terminal part defining a third bearing surface to bear against the first vertebra and a fourth bearing surface opposite said third bearing surface to bear against the second vertebra;   an elongated central part including first and second longitudinal walls extending along said longitudinal axis between said first and second terminal parts;   a cavity defined between said first and second terminal parts and between said first and second longitudinal walls; and   a projection extending transversely to said longitudinal walls and positioned between said cavity and said second terminal part, said projection configured to correspondingly penetrate the first or second vertebra when said first and third bearing surfaces bear against the first vertebra and said second and fourth bearing surfaces bear against the second vertebra, wherein said first and second bearing surfaces are separated by a first distance and said third and fourth bearing surfaces are separated by a second distance greater than said first distance to accommodate a spinal curvature, wherein said longitudinal walls define a substantially constant width of said body along said longitudinal axis and said width and said first distance are substantially the same.   
   
   
       32 . The implant of  claim 31 , wherein each of said first and second longitudinal walls projects transversely from said first and second terminal parts and includes a tapering edge adapted to penetrate the first vertebra and the second vertebra. 
   
   
       33 . The implant of  claim 32 , further comprising a second projection opposite said projection on said second terminal part, said second projection extending transversely to said first and second longitudinal walls and positioned between said cavity and said second terminal part, said second projection configured to correspondingly penetrate the first or second vertebrae when said first and third bearing surfaces bear against the first vertebra and said second and fourth bearing surfaces bear against the second vertebra. 
   
   
       34 . The implant of  claim 33 , wherein said first projection, said second projection and said tapering edges of said longitudinal walls define an opening into said cavity. 
   
   
       35 . The implant of  claim 34 , wherein said tapering edge of each of said first and second longitudinal walls extends in a longitudinal direction along said longitudinal axis. 
   
   
       36 . The implant of  claim 31  wherein:
 said first terminal part includes a first flange defining said first bearing surface and a second flange defining said second bearing surface; and   said second terminal part includes a third flange defining said third bearing surface and a fourth flange defining said fourth bearing surface.   
   
   
       37 . The implant of  claim 31  wherein said first, second, third, and fourth bearing surfaces are generally flat. 
   
   
       38 . The implant of  claim 31 , wherein said first and second longitudinal walls each have a generally trapezoidal contour. 
   
   
       39 . The implant of  claim 31 , wherein said cavity holds bone graft material. 
   
   
       40 . The implant of  claim 31 , wherein at least a portion of the implant is composed of a porous material. 
   
   
       41 . The implant of  claim 31 , wherein said first and second terminal parts each include a transverse face at a respective end of said body, each of said transverse faces including a centrally located threaded hole extending along said longitudinal axis. 
   
   
       42 . An implant for insertion between a first vertebra and a second vertebra, comprising an elongated body extending along a longitudinal axis, said body including:
 a first terminal part on said longitudinal axis defining a first bearing surface to bear against the first vertebra and a second bearing surface opposite said first bearing surface to bear against the second vertebra;   a second terminal part on said longitudinal axis opposite said first terminal part, said second terminal part defining a third bearing surface to bear against the first vertebra and a fourth bearing surface opposite said third bearing surface to bear against the second vertebra;   an elongated central part including a pair of longitudinal walls extending along said longitudinal axis between said first and second terminal parts;   a cavity defined between said first and second terminal parts and between said pair of longitudinal walls, wherein said pair of longitudinal walls define a constant width of said body along said longitudinal axis;   a first projection extending transversely to and between said pair of longitudinal walls, said first projection positioned between said cavity and said second terminal part, said first projection configured to correspondingly penetrate the first vertebra when said first and third bearing surfaces bear against the first vertebra and said second and fourth bearing surfaces bear against the second vertebra; and   a second projection extending transversely to and between said pair of longitudinal walls, said second projection being positioned between said cavity and said second terminal part, said second projection configured to correspondingly penetrate the second vertebra when said first and third bearing surfaces bear against the first vertebra and said second and fourth bearing surfaces bear against the second vertebra.   
   
   
       43 . The implant of  claim 42 , wherein said first and second bearing surfaces are separated by a first distance and said third and fourth bearing surfaces are separated by a second distance greater than said first distance to accommodate a spinal curvature. 
   
   
       44 . The implant of  claim 43 , further comprising:
 a third projection extending transversely to and between said pair of longitudinal walls, said third projection positioned between said cavity and said first terminal part, said third projection configured to correspondingly penetrate the first vertebra when said first and third bearing surfaces bear against the first vertebra and said second and fourth bearing surfaces bear against the second vertebra; and   a fourth projection extending transversely to and between said pair of longitudinal walls, said fourth projection being positioned between said cavity and said first terminal part, said fourth projection configured to correspondingly penetrate the second vertebra when said first and third bearing surfaces bear against the first vertebra and said second and fourth bearing surfaces bear against the second vertebra.   
   
   
       45 . The implant of  claim 44 , wherein each of said longitudinal walls includes a first tapering edge and an opposite second tapering edge, said first and second tapering edges are configured to penetrate opposing endplates of the first and second vertebrae. 
   
   
       46 . The implant of  claim 45 , wherein said first tapering edges of said longitudinal walls, said first projection, and said third projection define an opening into said cavity. 
   
   
       47 . The implant of  claim 42 , wherein at least a portion of the implant is composed of a resorbable material. 
   
   
       48 . The implant of  claim 42 , wherein said first and second terminal parts each include a transverse face at a respective end of said body, each of said transverse faces including a centrally located threaded hole extending along said longitudinal axis. 
   
   
       49 . The implant of  claim 42 , wherein said first, second, third, and fourth bearing surfaces are generally flat. 
   
   
       50 . The implant of  claim 42 , wherein each of said longitudinal walls has a generally trapezoidal contour.