An intervertebral implant and associated method. The intervertebral
implant can include a first component having a first articulating surface
and a first bone engagement surface for engaging a first vertebra, and a
second component having a second articulating surface and a second bone
engagement surface for engaging a second vertebra adjacent to the first
vertebra. The first and second articulating surfaces can articulate with
each other for substantially replicating a natural spinal movement. The
first and second bone engagement surfaces can define an outer surface
substantially shaped as an envelope of two intersecting cylinders. In one
aspect, the first and second articulating surfaces can have substantially
equal radii of curvature in a coronal plane and different radii of
curvature in a sagittal plane.