Patent ID: 8167948

Claim:
An intervertebral prosthetic disc comprising: a first endplate having a first surface configured to substantially engage with a first vertebral body and a second surface comprising a contoured, partially spherical articulating surface; a second endplate having a first surface configured to substantially engage with a second vertebral body and a second surface comprising a contoured, partially cylindrical articulating surface, the second endplate including a sidewall including one or more notches formed therein; a core element at least partially disposed between the first and second endplates, wherein the core element comprises a first contoured surface in communication with and substantially corresponding to the curvature of the second surface of the first endplate, and a second contoured surface substantially in communication with and substantially corresponding to the curvature of the second surface of the second endplate, wherein the first surface of the first endplate has a first keel configured to engage with a groove in the first vertebral body and the first surface of the second endplate has a second keel configured to engage with a groove in the second vertebral body, wherein at least one of the first and second keels has at least one slot extending a length downwardly from a distal edge of the keel to the base of the keel, and wherein the at least one of the first and second keels includes a leading edge that includes a chamfer for aligning and inserting the keel into the groove in the first and second vertebral body.