Patent ID: 8118871

Claim:
An intervertebral implant for a human spine, comprising: an upper body comprising an upper portion and a lower portion, the upper portion and the lower portion each comprising a superior surface and an inferior surface, wherein the superior surface of the upper portion is configured to engage a first vertebra of the human spine, wherein at least a portion of the inferior surface of the upper portion of the upper body is substantially concave, wherein at least a portion of the superior surface of the lower portion of the upper body is substantially convex, and wherein the concave portion of the inferior surface of the upper portion of the upper body is configured to be coupled to the convex portion of the superior surface of the lower portion of the upper body; a lower body comprising a superior surface and an inferior surface, wherein the inferior surface of the lower body is configured to engage a second vertebra of the human spine, wherein the inferior surface of the upper body and/or the superior surface of the lower body comprises one or more cam ramps; an insert configured to be positioned between the inferior surface of the lower portion of the upper body and the superior surface of the lower body, wherein the insert is configured to rotate about a rotational axis, wherein the rotational axis passes through at least a portion of the insert, and wherein the insert comprises at least one projection extending radially with respect to the rotational axis; and an advancing element configured to be advanced linearly to engage at least one of the projections of the insert at a position radially offset from the rotational axis such that linear advancement of the advancing element at least partially rotates the insert about the rotational axis; wherein rotation of the insert about the rotational axis causes at least a portion of the insert to travel along at least a portion of at least one of the cam ramps to increase a separation distance between the insert and the inferior surface of the upper body and/or the superior surface of the lower body, and wherein increasing the separation distance between the insert and the inferior surface of the upper body and/or the superior surface of the lower body is configured to increase a separation distance between the upper body and the lower body to increase a height of the intervertebral implant.