Patent ID: 7270681

Claim:
A spinal implant comprising an articulating means configured to be interposed between a first vertebra and a second vertebra, wherein said articulating means permits an articulation of said first vertebra and said second vertebra along a sagittal plane and about an instantaneous axis of rotation wherein said articulating means is defined by first and second articulating implant components defining abutting articulation surfaces forming said articulating means, and wherein one of said abutting articulation surfaces comprises a convex and another of said abutting articulation surfaces comprises a non-concave surface, said convex surface positioned in direct abutment against said non-concave surface during normal operational movement of the spinal implant to provide relative articulating movement of said first and second implant components along the sagittal plane during flexion and extension movement of said first and second vertebrae, whereby said articulation of said first vertebra and said second vertebra is substantially similar to the bio-mechanical motion of a substantially identical pair of adjacent vertebrae interacting with a natural intervertebral disc; and wherein said articulating means comprises an elongate rocker rail extending along a length of one of said first and second articulating implant components and an elongate channel extending along a length of the other of said first and second articulating implant components, at least a portion of said elongate rocker rail positioned within said elongate channel to provide said articulation of the first and second vertebrae.