ANTERIOR CERVICAL PLATE

摘要

An anterior cervical plate system is provided. The cervical plate includes a retention ring with a deflectable flange that is upwardly spaced from the top surface of the ring and configured to prevent an inserted bone fastener from backing out of the plate. The plate includes a locking pin having a camming surface and a blocking surface. When the camming surface is moved into position adjacent to the flange, the flange is free to flex out of the way of a bone screw being inserted into or removed from the plate. When the blocking surface is positioned adjacent to the flange, outward deflection of the flange is prevented to retain the bone screw inside the plate. The locking pin is rotated through a camming surface to bring a blocking surface against the flange deflecting the flange onto the head of the bone screw.

主权项

1. A bone plate, comprising:
a plate having at least one through hole configured to receive a bone screw for attaching the plate to bone; a retention ring disposed inside the at least one through hole; the retention ring including a central aperture having an entry opening at a top surface; the retention ring including a resiliently deflectable retention flange upwardly spaced from the top surface of the retention ring; the retention flange having a portion extending radially inwardly above the entry opening when in a normal undeflected position; a bone screw having a head portion connected to a shank portion; the bone screw being configured for insertion into the through hole and into the central aperture of the retention ring such that at least a portion of the head portion is positioned distally of the retention flange; and a locking pin being movably connected with respect to the plate and mechanically coupled to at least one adjacent retention flange; the locking pin having at least one blocking surface; wherein the bone plate includes a locked position in which the blocking surface of the locking pin is moved into a position adjacent to the retention flange to prevent outward deflection of the retention flange and thereby maintain the retention flange in the pathway of the entry opening and above the bone screw to prevent the bone screw from backing out of the through hole.