Abstract: A system for dynamic stabilization of the spine includes a bone engaging fastener configured to be anchored in a vertebra and a deflectable element mounted on the fastener. The deflectable element or bumper is configured and arranged to contact a portion of an adjacent vertebra, such as the facet, during extension of the spine, while offering no resistance during flexion. In certain embodiments, a cable may be fastened to the bone engaging fastener and arranged to contact a portion of the adjacent vertebra, such as the spinous process, during flexion of the spine. In one surgical technique of the invention, a contralateral approach is used to introduce the bone engaging fastener through the deflectable element and into the vertebra.

Abstract: In one embodiment, the invention relates to a composition suitable for preparing a hydrogel useful as replacement material for all or part of a disc nucleus. The composition comprises: a curable, cross-linkable, non-immunogenic, non-toxic protein comprising a minimum of about 10% and a maximum of about 25% of the hydrogel by weight; a metal contrast agent comprising a minimum of about 2% and a maximum of about 70% of the hydrogel by weight; and a crosslinker comprising a minimum of about 0.1% and a maximum of about 10% of the hydrogel by weight; wherein the composition has a discernable radiopacity level.