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US 8,617,224 B2Granted
Anterior lumbar plate and method
AssigneeWarsaw Orthopedic, Inc.
InventorsJeffrey Kozak, Bradley T. Estes, Lawrence M. Boyd
Life of this patent
Estimating the term…
Abstract
A plate of biocompatible material is provided having curvature in two planes such that it conforms to the curvature of the L5 vertebral body and to the patient's lordotic curve. Holes are provided receiving screws for anchorage in the vertebral body and sacrum. A flange or foot portion on the plate provides a wider base end area for support in the L5-S1 interspace. The foot portion is also arranged for appropriate entry angle of screws into the sacrum such as to improve anchorage in the sacrum. Anti-backout and low profile features are incorporated. The anterior lumbar plate is situated to maintain the anterior interbody bone graft in compression by resisting tensile forces during extension.
Claims17
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.
3 more elements
An apparatus, comprising:
- an anterior orthopedic plate for attachment and joining of multiple vertebrae 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;
- first and second bone screws, said first bone screw inserted through one of said holes in said upper portion and said second bone screw inserted through the other of said holes in said upper portion;
- third and fourth bone screws, said third bone screw inserted through one of said holes in said lower portion and said fourth bone screw inserted through the other of said holes in said lower portion;
- and
- an anti-backout system for maintaining at least two of said bone screws in said plate, said anti-backout system including an anti-backout screw received in said plate and a head portion with a surface for covering the exterior surface of at least one of said bone screws to prevent backing out of said at least one of said bone screws upon fixation of said anti-backout system.
2 more elements
An anterior orthopedic plate system with an anti-backout device for maintaining bone screws in the plate, comprising:
- 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, wherein said plate includes a longitudinal axis and slot about midway between said upper surface and said lower surface, said slot having a length dimension substantially perpendicular to said longitudinal axis and a width dimension smaller than said length dimension and substantially parallel to said longitudinal axis, said slot allowing said plate to be bent approximately at the conjunction of said upper portion and said lower portion, and
- wherein two bone screw holes are formed in said upper portion, said bone screw holes in said upper portion being separated by a first distance, and two bone screw holes are formed in said lower portion, said bone screw holes in said lower portion being separated by a second distance that is greater than said first distance, and
- wherein said anti-backout device is adjacent to said bone screw holes in said upper portion to prevent screws in said bone screw holes in said upper portion from backing out of the plate through said bone screw holes in said upper portion.
Dependencies are inferred from the claim text.