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

Claim 11:
12. A method of inserting an intervertebral prosthesis between adjacent vertebrae, the method comprising:
providing an intervertebral disc 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 within the core configured to receive the first and second central projections, wherein each of the first central projection and the second central projection have a diameter that is smaller than a smallest diameter of the central opening; 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 prevent 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
inserting the intervertebral disc between the first and second vertebrae with an insertion instrument configured to hold the upper and lower plates and core in a fixed configuration until released from the insertion instrument.