Patent Number: 8,870,931

Title: Anti-unscrewing and multi-angular fastening apparatuses and methods for surgical bone screw/plate systems

Abstract: A fastening apparatus includes a fastener and a fastener receiving member. The apparatus enables the fastener to be affixed to the fastener receiving member at a variable insertion angle selected by the user and further provides an anti-unscrewing feature. The fastener includes an elongate section and an adjoining head section having at least one slot therein. The fastener receiving member includes one or more apertures having a contact region through which one or more corresponding fasteners can be inserted. The contact region includes a matrix of protrusions having a density and strength sufficient to render contact region tappable by the thread of the head section of the fastener. The thread on the head section is driven into the contact region at the selected insertion angle. As a result, the protrusions project into the at least one slot to prevent the fastener from backing out of the fastener receiving member. A fastener driver is also disclosed.

Inventors: Dahners; Laurence E. (Chapel Hill, NC), Warner; Nicholas F. (Cummington, MA)

Assignee: The University of North Carolina at Chapel Hill

International Classification: A61B 17/80 (20060101); A61B 17/84 (20060101)

Expiration Date: 2018-10-28 0:00:00