Intervertebral implants

Abstract

A multipart intervertebral implant is provided which includes an implant portion and an implant extender portion. The implant portion and the implant extender portion can be fastened together using any known fastening means including pins, interlocking structure (e.g., dovetail, tongue and groove, etc.), adhesives, etc. The size of the implant extender portion can be selected during a surgical procedure to provide an implant suitable for a particular intervertebral receiving bed. An intervertebral implant is also provided which may be formed from a multiplicity of implant sections which are fastened together to provide an implant having a desired length. Implants having surface configurations which more closely correspond to the configuration of vertebral endplates are also provided.

Description

[0001] This application claims priority from United States provisional application Ser. No. 60 / 173,973, filed Dec. 30, 1999, which is incorporated herein by reference.[0002] 1. Technical Field[0003] The present disclosure relates generally to biocompatible implants and, more particularly, to intervertebral implants suitable for implantation into the lumbar, thoracic and / or cervical regions of the spine during a spinal fusion procedure.[0004] 2. Background of Related Art[0005] Intervertebral implants for fusing together adjacent vertebrae of a spinal column are well known in the art. Such implants are formed in a variety of different shapes and sizes and are configured for insertion into receiving beds formed in the lumbar, thoracic and cervical regions of the spine. The implants may be formed from a variety of different biologically compatible materials including ceramics, polymers, human or animal bone, composites, etc. The implants may also be shaped to maintain the natural lordos...

AI Technical Summary

Problems solved by technology

One problem associated with known implants is the difficulty in adapting an implant to meet the size requirements of a particular intervertebral receiving bed.

For example, because anatomically all patients are different, the specific size of implant required for a surgical procedure will not be known to any certainty until a surgeon has prepared the intervertebral space for implantation.

Another problem associated with known implants constructed from bone is that the anatomical limitations of donor bone limit the size of the implant which can be formed from bone.

As a result, bone having satisfactory strength characteristics may not be available for use as an implant because of size limitations

Finally, yet another problem associated with known implants is their inability to accurately maintain the natural lordoses of the spine.

Because of the irregular shape of the vertebral endplates, wedge-shaped implants and cylindrical dowels are incapable of supporting adjacent vertebrae in their natural orientation without substantially altering the shape of the vertebral endplate(s).

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