Orthopedic prosthesis having anti-backout screw

摘要

An implantable orthopedic prosthesis includes a screw having a threaded shank and a head. The head includes a plurality of splines extending outwardly of the diametrical extent of the head. A first implantable prosthetic element has a threaded bore for receiving the threaded shank of the screw in threaded engagement. A second implantable prosthetic element has a shoulder-stepped bore for receiving the threaded shank therethrough and for engaging the head. The bore includes an annular groove for receiving the splines of the head and defines a shoulder for engaging the splines to prevent backout of the screw.