Patent ID: 8062367

Claim:
A plate system for mounting on a spinal column, said plate system comprising: a plate having a plurality of openings; and a plurality of screws for receipt in said plurality of openings, respectively, and screwed into a spinal bone of said spinal column; said plurality of screws having heads that engage to retain said plurality of screws in a tightened position; each of said plurality of screws having a threaded portion monolithically formed with a head, a head of at least one of said plurality of screws being situated adjacent to an adjacent one of said plurality of screws after said at least one of said plurality of screws and said adjacent one of said plurality of screws are received in said plate, said head of said at least one of said plurality of screws comprises a first portion sized and shaped to permit said adjacent one of said plurality of screws to be screwed into bone and after it is screwed into bone, said at least one of said plurality of screws can be screwed into bone so that a second portion of said head of said at least one of said plurality of screws engages a head of said adjacent one of said plurality of screws to retain said plurality of screws in said tightened position; wherein said first portion comprises a first radius and said second portion comprises a second radius that is larger than said first radius.