US Patent 7935137 Locking bone screw and spinal plate system

A bone plate system including a bone plate and a bone screw with an integrated locking mechanism is disclosed. The bone screw includes an elongate member having a threaded shank and a bone screw head that is radially deformable. The integrated locking mechanism sits within the bone screw head and can rotate between a locked condition and an unlocked condition. When the bone screw head is seated within an aperture in the bone plate, rotating the integrated locking mechanism into the locked condition helps to prevent bone screw backout.