Implantable device for facet joint replacement

Abstract

Cephalad and caudal vertebral facet joint prostheses and methods of use are provided. The prostheses provide an artificial facet joint structure including an artificial articular configuration unlike the preexisting articular configuration. The radii and material stress values of the prostheses are configured to sustain contact stress. The cephalad prosthesis provides for posterior-anterior adjustment. Both prostheses permit lateral adjustment and adjustment to accomodate interpedicle distance. Further, the prostheses may be customized to provide a pre-defined lordotic angle and a pre-defined pedicle entry angle.

Description

RELATED APPLICATIONS

[0001] This application is a continuation-in-part of U.S. patent application Ser. No. 10 / 067,137, filed Feb. 4, 2002, and entitled “Facet Arthroplasty Devices and Methods,” which is a continuation-in-part of U.S. patent application Ser. No. 09 / 693,272, filed Oct. 20, 2000, and entitled “Facet Arthroplasty Devices and Methods,” which claims the benefit of Provisional Patent Application Ser. No. 60 / 160,891, filed Oct. 22, 1999, and entitled “Facet Arthroplasty Devices and Methods,” all of which are incorporated herein by reference.FIELD OF THE INVENTION

[0002] This invention relates to prostheses for treating various types of spinal pathologies, as well as to methods of treating spinal pathologies. BACKGROUND OF THE INVENTION I. Vertebral Anatomy

[0003] As FIG. 1 shows, the human spinal column 10 is comprised of a series of thirty-three stacked vertebrae 12 divided into five regions. The cervical region includes seven vertebrae 12, known as C1-C7. The thoracic re...

Examples

Embodiment Construction

[0066] Although the disclosure hereof is detailed and exact to enable those skilled in the art to practice the invention, the physical embodiments herein disclosed merely exemplify the invention that may be embodied in other specific structure. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims.

I. Vertebral Prostheses

[0067] FIGS. 4 to 6 illustrate various prostheses for replacing inferior and / or superior portions of natural facet joints. The prostheses are desirably fixed to vertebral bodies following the surgical removal of the respective natural facet joint portions from the vertebral bodies.

[0068]FIG. 4 shows a cephalad prosthesis 36 for replacement of the natural inferior half of a facet joint following removal of the natural inferior half of the facet joint. FIG. 5 shows a caudal prosthesis 38 for replacement of the natural superior half of a facet joint following removal of the ...

RELATED APPLICATIONS

[0001] This application is a continuation-in-part of U.S. patent application Ser. No. 10 / 067,137, filed Feb. 4, 2002, and entitled “Facet Arthroplasty Devices and Methods,” which is a continuation-in-part of U.S. patent application Ser. No. 09 / 693,272, filed Oct. 20, 2000, and entitled “Facet Arthroplasty Devices and Methods,” which claims the benefit of Provisional Patent Application Ser. No. 60 / 160,891, filed Oct. 22, 1999, and entitled “Facet Arthroplasty Devices and Methods,” all of which are incorporated herein by reference.FIELD OF THE INVENTION

[0002] This invention relates to prostheses for treating various types of spinal pathologies, as well as to methods of treating spinal pathologies. BACKGROUND OF THE INVENTION I. Vertebral Anatomy

[0003] As FIG. 1 shows, the human spinal column 10 is comprised of a series of thirty-three stacked vertebrae 12 divided into five regions. The cervical region includes seven vertebrae 12, known as C1-C7. The thoracic re...

Examples

Embodiment Construction

[0066] Although the disclosure hereof is detailed and exact to enable those skilled in the art to practice the invention, the physical embodiments herein disclosed merely exemplify the invention that may be embodied in other specific structure. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims.

I. Vertebral Prostheses

[0067] FIGS. 4 to 6 illustrate various prostheses for replacing inferior and / or superior portions of natural facet joints. The prostheses are desirably fixed to vertebral bodies following the surgical removal of the respective natural facet joint portions from the vertebral bodies.

[0068]FIG. 4 shows a cephalad prosthesis 36 for replacement of the natural inferior half of a facet joint following removal of the natural inferior half of the facet joint. FIG. 5 shows a caudal prosthesis 38 for replacement of the natural superior half of a facet joint following removal of the ...

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