Patent ID: 7311732

Claim:
An intervertebral prosthesis comprising: a prosthesis core; a standard cover plate which encloses the prosthesis core via a first internal engaging surface; and a corrective cover plate which encloses the prosthesis core via a second internal engaging surface, the second internal engaging surface having an anterior rise and a posterior rise defining a concave second internal engaging surface, the posterior rise being greater than the anterior rise; wherein the standard cover plate has a first external surface of a first extent between a first dorsal edge and a first ventral edge across an entire sagittal section of the intervertebral prosthesis, the first external surface configured to contact a first vertebral surface and having a predetermined position in relation to the first vertebral surface, and wherein the corrective cover plate has a second external surface of a second extent between a second dorsal edge and a second ventral edge across an entire sagittal section of the intervertebral prosthesis, the second external surface being configured to contact a second vertebral surface, the corrective cover plate having a first ventral thickness at the second ventral edge and a second dorsal thickness in sagittal section at the second dorsal edge; the second extent of the corrective cover plate being greater than the first extent of the standard cover plate in an anterior-posterior direction dorsally, and the second dorsal thickness being greater than the first ventral thickness wherein a dorsal thickening of the corrective cover plate is wedge-shaped, said wedge shape starting at the posterior rise and terminating at the second dorsal edge.