摘要 |
<p>This invention is a prosthetic nucleus (5) for implantation in a chamber of an intervertebral disc after removal of at least a portion of a damaged or degenerated nucleus from the chamber, comprising a wafer of biologically compatible, thin, flexible, and expandable material in a selcted first configuration. The wafer (5) is adapted to be reshaped mechanically into a compact second configuration of cross section sufficiently small to permit travel of the wafer through a cannula (100), and into the disc chamber (215). The wafer is further adapted to substantially regain the first configuration thereof by memory upon entry into the disc chamber. The wafer is adapted to react to an expansion inducing agent in the disc chamber to expand an enlarged and selected third configuration.</p> |