Track-plate carriage system

Abstract

Translational bone fixation assemblies, kits containing such assemblies, and methods of use are described herein. The described assemblies may be used in spinal fusion procedures in which a damaged or diseased disc (or part of a disc) is removed from between a pair of vertebrae and a spinal fusion spacer is placed between the vertebrae. The assemblies may be applied to an anterior portion of the affected vertebrae to span the affected disc space, and may be fixed to the vertebrae using bone screws. The assemblies may function to maintain the vertebrae aligned during the initial period following fixation in which fusion of the spacer to the adjacent vertebrae occurs. The assemblies may also function to share some of the axial spinal load applied to the fusion spacer to prevent extreme subsidence of the spacer into the vertebral body, such as where the patient has poor bone quality. The assemblies may also act to prevent the spacer from being expelled from the disc space during the initial post-operative period. Finally, these assemblies may be used in other parts of the body where the advantages of the assemblies are desired or applicable.

Description

CROSS-REFERENCE TO RELATED APPLICATION [0001] This application is a continuation-in-part of co-pending United States non-provisional patent application Ser. No. 10 / 653,164, entitled “Bone Plate with Captive Clips”, by Duong, et al., filed Sep. 3, 2003, the entire disclosure of which application is expressly incorporated by reference herein.FIELD OF THE INVENTION [0002] The present invention is related to a fixation system. More particularly, the invention is related to a fixation system consisting of a translational plate system with a plurality of fixation holes. BACKGROUND OF THE INVENTION [0003] Orthopedic fixation devices such as plates are frequently coupled to bone with fasteners inserted through plate holes. It is known that securing such fasteners to the bone plate, for example through the use of expansion-head screws, can decrease the incidence of loosening of the fixation assembly post-operatively. It is also known that a bushing may be disposed in each plate hole to recei...

AI Technical Summary

Benefits of technology

[0014] The first plate may have four fixation holes, and wherein the fixation holes are arranged in pairs. The first plate further may comprise at least one indent able to facilitate the bending of the first plate. At least two fixation holes may be substantially circular, and may further comprise a clip. At least two fixation holes may be substantially oblong. At least two fixation holes may each have a longitudinal axis, and wherein the at least two fixation holes allow for the translation of a fastener along the longitudinal axis of each of the at least two fixation holes. At least two fixation holes may allow for selective placement of a fastener within each of the at least two fixation holes.

Problems solved by technology

However, polyaxial movement of fasteners through set plate hole locations only increases attachment alternatives of the fasteners themselves.

Where a rigid fixation plate is used to connect the vertebrae, this subsidence may tend to shift more of the spinal load to the plate than is desirable.

Such load shifting can also occur due to inaccuracies in installing the plate to the vertebrae.

In extreme circumstances, this load shifting can result in non-fusion of the spacer to the vertebra, since firm compression between the spacer and the vertebrae is one factor contributing to successful fusion.

Images