an intervertebral disc prosthesis that comprises a deformable flexure with an axial cavity , the axial cavity extending along the axis of the flexure , and a slit defined in the perimeter surface of the flexure to provide flexibility to the disc member , the slit having a slit thickness . the slit may be in the form of a coil to impart a spring - like appearance and function . the intervertebral disc prosthesis further comprises a lower disc support housed in the axial cavity and an upper disc support housed in the axial cavity , with the lower and upper disc supports communicating with one another to provide support to the disc . the lower or upper disc support may alternatively be incorporated into the flexure .