Patent ID: 8617224

Claim:
An anti-backout system for screws, said system forming part of an anterior orthopedic plate system for attachment and joining of multiple vertebrae, said system comprising: a bone screw having a threaded portion received through an aperture in a member and having a head prevented from movement through said aperture by a stop surface on said member, the head having a tapered exterior surface thereon; and an anti-backout screw received in said member such that axes defined by said bone screw and said anti-backout screw extend parallel to one another, said anti-backout screw having a head thereon with a tapered exterior surface matable with the exterior surface of said bone screw to prevent relative rotational movement between said screws upon mating engagement of said tapered surface; wherein said member is an orthopedic plate having an anterior surface and an opposed posterior surface for facing the vertebrae, said plate further having an upper portion and a lower portion, said upper and lower portions directly coming together, said upper portion having two opposed side surfaces and an upper surface each bounding said anterior and posterior surfaces, said opposed side surfaces of said upper portion being parallel and having a first thickness, said opposed side surfaces of said upper portion having a first width measured between them, and said lower portion having two opposed side surfaces and a lower surface each bounding said anterior and posterior surfaces, said opposed side surfaces of said lower surface being curved outward away from each other, so that a second width measured between said opposed side surfaces of said lower surface is larger than said first width, said opposed side surfaces having a thickness that gets larger from the place where said upper and lower portions come together toward said lower surface, said upper portion having two holes for bone screws separated by a first distance, said lower portion having two holes for bone screws separated by a second distance that is greater than said first distance, and said holes in said lower portion each having a rim and a secondary threaded hole through said rim and below said anterior surface; wherein said bone screw is inserted through one of said holes in said upper and lower portions, and wherein said anti-backout screw is inserted into said plate.