The invention relates to an artificial intervertebral disc for placement
between adjacent vertebrae. The artificial intervertebral disc is
preferably designed to restore disc height and lordosis, allow for a
natural range of motion, absorb shock and provide resistance to motion
and axial compression. Furthermore, the intervertebral disc may be used
in the cervical, the thoracic, or the lumber regions of the spine. The
artificial intervertebral disc may include either singularly or in
combination: an interior at least partially filled with a fluid; a valve
for injecting fluid into the interior of the disk; a central region
having a stiffness that is preferably greater than the stiffness of the
outer regions thus enabling the disc to pivot about the central region.
The central pivot may be formed by a center opening, a central chamber,
an inner core or a central cable.