Patent ID: 9101407
Filing Date: 2015-08-11
Classification: A61B

Abstract:
1. A bone plate system, 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 through hole; the retention ring including a central aperture having a entry opening at a top surface and an exit opening at a bottom surface; the central aperture defining a central axis; the retention ring further including an inner surface interconnected to an outer surface with each extending between the top surface and the bottom surface; the retention ring further including a plurality of slots spaced circumferentially around the retention ring; the slots extending from the top surface towards the bottom surface to form deflectable tabs between the slots; and 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; wherein the retention ring is configured such that the tabs are deflected inwardly towards the central axis when the retention ring is inserted into the at least one through hole such that the tabs cover at least a portion of the head portion of the bone screw inserted into the central aperture of the retention ring; wherein the retention ring further includes 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 and into an insertion pathway of the bone screw when in a normal undeflected position; and a locking pin configured to deflect the retention flange inwardly toward the central axis such that the retention flange contacts and exerts a force on at least a portion of the head of the bone screw inserted into the through hole and into the central aperture of the retention ring; the bone screw being inserted such that at least a portion of the head portion bone screw is positioned distally of the retention flange.