An artificial intervertebral disc includes an upper retaining member secured
to
an upper vertebra; a lower retaining member secured to a lower vertebra adjacent
to the upper vertebra; and a nucleus member rotatably coupled between the upper
and the lower retaining members, with the nucleus member having at least a cushioning
filler selected from: gel, foam, elastomers, and shock-absorbing materials filled,
formed or pre-formed in the nucleus member for making an artificial intervertebral
disc as universally oriented, stably supported, reliably manipulated and minimally invasive.