Peanut spectacle multi discoid thoraco-lumbar disc prosthesis
A disc prosthesis comprises a first prosthetic device comprising a first upper housing and a first lower housing between which at least one first disc element is movably interposed. The disc prosthesis further comprises a second prosthetic device comprising a second upper housing and a second lower housing between which at least one second disc element is movably interposed. The first and second prosthetic devices are adapted for parallel placement within an intervertebral space.
1 . A disc prosthesis comprising:
a first prosthetic device comprising a first upper housing and a first lower housing between which at least one first disc element is movably interposed and
a second prosthetic device comprising a second upper housing and a second lower housing between which at least one second disc element is movably interposed,
wherein the first and second prosthetic devices are adapted for parallel placement within an intervertebral space.
2 . The disc prosthesis of claim 1 wherein the at least one first disc element has opposite convex surfaces.
3 . The disc prosthesis of claim 1 wherein the first prosthetic device further comprises a first post extending from the first upper housing and the at least one first disc element further comprises a recess portion into which the first post is adapted to extend.
4 . The disc prosthesis of claim 1 wherein the first and second prosthetic devices are further adapted for separated placement within the intervertebral space.
5 . The disc prosthesis of claim 1 wherein the first prosthetic device further comprises a first sheath extending between the first upper and lower housings.
6 . The disc prosthesis of claim 5 wherein the first prosthetic device further comprises a circlage retainer for affixing the first sheath the first upper housing.
7 . The disc prosthesis of claim 1 wherein the first upper housing comprises a pair of rounded lobes.
8 . The disc prostheis of claim 1 wherein the first upper housing comprises a convex surface adapted to slidingly contact the at least one first disc element.
9 . The disc prosthesis of claim 8 wherein the first lower housing comprises a convex surface adapted to slidingly contact the at least one first disc element.
10 . The disc prosthesis of claim 1 wherein the at least one first disc element is adapted to rotate with respect to the first upper housing.
11 . A minimally invasive method of installing a functional spinal unit comprising:
creating at least one posterior opening in a patient;
accessing an intervertebral disc space through the at least one posterior opening;
inserting a first prosthetic device into the intervertebral disc space, wherein the first prosthetic device comprises a first upper housing and a first lower housing between which at least one first disc element is movably interposed; and
inserting a second prosthetic device into the intervertebral disc space and into generally parallel alignment with the first prosthetic device, wherein the second prosthetic device comprises a second upper housing and a second lower housing between which at least one second disc element is movably interposed.
12 . The method of claim 11 further comprising engaging the first upper housing with an upper vertebral endplate and engaging the first lower housing with a lower vertebral endplate.
13 . The method of claim 12 further comprising engaging the second upper housing with the upper vertebral endplate and engaging the second lower housing with the lower vertebral endplate.
14 . The method of claim 11 further comprising inserting the first prosthetic device as a single unit.
15 . The method of claim 11 wherein the at least one first disc element comprises a convex upper surface adapted for slidably engaging a convex surface of the first upper housing.
16 . The method of claim 15 wherein the at least one first disc element comprises a convex lower surface adapted for slidably engaging a convex surface of the first lower housing.
17 . The method of claim 11 wherein the first and second prosthetic devices are inserted into the intervertebral disc space through the at least one posterior opening.
18 . The method of claim 11 further comprising limiting motion of the at least one first disc element relative to the first upper and lower housings with a post extending from one of the first housings into a recess in the at least one first disc element.
19 . The method of claim 11 wherein the first prosthetic device further comprises a sheath extending between the first upper and lower housings.
20 . The method of claim 19 wherein the first prosthetic device further comprises a circlage retainer for affixing the sheath to the first upper housing.