Patent ID: 8506631

Claim:
A system for insertion of an intervertebral disc prosthesis into an intervertebral space, the system comprising: an intervertebral disc comprising: upper and lower supports each having an outer surface configured to engage a vertebra and an inner surface; and a plurality of selectable shock absorbing intervertebral disc prosthesis cores configured to be received between the inner surfaces of the upper and lower supports and to slide over the inner surfaces of the upper and lower supports to provide articulation of the intervertebral disc; and an instrument comprising a distractor tip with a channel dimensioned to pass the prosthesis, wherein the distractor tip is capable of compressing at least one of the plurality of cores from an expanded profile configuration to a narrow profile configuration when the prosthesis slides along the channel toward the intervertebral space; wherein the plurality of selectable cores, each comprise: upper and lower surfaces; and at least one of a resilient material or a resilient member disposed between the upper and lower surfaces to allow the upper and lower surfaces to move resiliently toward and away from each other; wherein the instrument includes a spring configured to press the upper and lower supports together when the upper and lower supports and a selected core are placed in the channel of the instrument.