Patent ID: 11911286
Assignee: SIMPLIFY MEDICAL PTY LTD.
Field: Medical technology (Instruments)
Classification: CPC A | IPC A

Claim 8:
9. An intervertebral prosthesis for insertion between adjacent vertebrae, the prosthesis comprising:
a first plate having an outer surface locatable against a first vertebra and an inner curved surface, wherein a first central projection extends from the inner curved surface and includes a tapered portion a distance from the first plate, wherein
the outer surface of the first plate includes an outer portion having a plurality of pyramidal serrations and an inner portion having a first plurality of truncated pyramidal serrations, and
an intermediate portion of the first plate between the outer portion and the inner portion includes a second plurality of truncated pyramidal serrations, wherein the second plurality of truncated pyramidal serrations are truncated to a lesser degree with respect to the plurality of pyramidal serrations than the first plurality of truncated pyramidal serrations;

a second plate having an outer surface locatable against a second vertebra and an inner curved surface, wherein a second central projection extends from the inner curved surface toward the first plate;
a ring shaped core having a cross section with a trapezoidal shape, the core having upper and lower curved surfaces complementary in shape to the inner curved surfaces of the first and second plates to allow the plates to slide over the upper and lower surfaces of the core, and a central opening in the core configured to receive the first and second central projections; and
wherein the first central projection having the tapered portion, the second central projection and the central opening cooperate with one another to retain the core between the plates and limit motion of the first and second plate with respect to one another to limit contact between annular perimeter surfaces of the first plate and the second plate during sliding movement of the first plate and the second plate over the core, and
wherein the inner curved surface of the first plate and an inner curved surface of the second plate define a diameter that is substantially equal to an overall diameter of the core.