Patent ID: 8915964

Claim:
An intervertebral spacer for placement between an upper vertebra and a lower vertebra, the intervertebral spacer comprising: a first endplate having an outer surface configured to contact one of the upper vertebra and lower vertebra, the first endplate having an inner surface opposite the outer surface and a pin element extending from the inner surface; a second endplate having an outer surface configured to contact the other of the upper vertebra and lower vertebra, the second endplate having an inner surface opposite the outer surface of the second endplate and a recessed portion extending into the inner surface of the second endplate, the inner surface of the first endplate facing the inner surface of the second endplate in an assembled configuration; and at least one articulation element having an outer perimeter, a plurality of segments disposed within the outer perimeter, a space separating adjacent ones of the plurality of segments and a bridging element connecting adjacent ones of the plurality of segments, the bridging element including a first sidewall and a second sidewall spaced from the first sidewall in a circumferential direction, the space including a first terminal end defined by the first sidewall, a second terminal end defined by the second sidewall, and a length that extends continuously from the first terminal end in the circumferential direction to the second terminal end, the at least one articulation element having an outermost one of the plurality of segments and an innermost one of the plurality of segments that is disposed within the outermost segment, such that the outermost segment is positioned closer to the outer perimeter than the innermost segment, wherein in the assembled configuration, the at least one articulation element receives the pin element, and the at least one articulation element is received within the recessed portion to permit relative movement of the endplates by flexing of the at least one articulation element without opposed surfaces of adjacent segments rubbing against each other.