Cervical disc replacement

An apparatus for replacing at least a portion of an intervertebral disc in a spinal column, comprising:

• first means for engagement with an endplate of a first vertebral bone in the spinal column;
• and
• second means for engagement with an endplate of a second vertebral bone in the spinal column, wherein:
• an intervertebral disc space is defined substantially between the first and second endplates of the first and second vertebral bones, and
• the first and second means are operable to articulate relative to one another, when the first and second means are disposed in the intervertebral disc space, about at least one of:
• (i) a first center of rotation for at least one of flexion and extension that is located outside the intervertebral disc space, and (ii) a second center of rotation for lateral bending that is located outside the intervertebral disc space.

An apparatus for replacing at least a portion of an intervertebral disc in a spinal column, comprising:

• a first member having a first vertebral contact surface for engagement with an endplate of a first vertebral bone in the spinal column, and having a first articulation means;
• and
• a second member having a second vertebral contact surface for engagement with an endplate of a second vertebral bone in the spinal column, and having a second articulation means, wherein:
• an intervertebral disc space is defined substantially between the first and second endplates of the first and second vertebral bones, and
• the first and second articulation means are operable to articulate relative to one another, when the first and second members are disposed in the intervertebral disc space, about at least one of:
• (i) a first center of rotation for at least one of flexion and extension that is located outside the intervertebral disc space, and (ii) a second center of rotation for lateral bending that is located outside the intervertebral disc space.