Patent ID: 8540772

Claim:
A nucleus replacement that mimics a native annulus in shape and function for use in partial disc arthroplasty, the nucleus replacement comprising: at least one jacket including a compartment, a first anchoring limb on one side of the compartment, and a second anchoring limb on an opposite side of the compartment, the at least one jacket being insertable into a disc space with the first and second anchoring limbs on opposite lateral sides of the disc space; a shock absorbing material injectable into the compartment after installing the at least one jacket into the disc space, the shock absorbing material including characteristics that absorb loads on the replacement; and a pair of intraosseous anchoring members cooperable with the first and second anchoring limbs, respectively, the intraosseous anchoring members securing the nucleus replacement in the disc space, wherein one of the first anchoring limb and the second anchoring limb is sealed, and the other of the first and second anchoring limbs comprises a valve that provides external access to the compartment.