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...http://www.google.com/patents/US20060293663?utm_source=gb-gplus-sharePatent US20060293663 - Dynamic stabilization system for the spine
