US Patent 7892285 Universal joint total disc replacement

A vertebral disc replacement includes superior and inferior end plates separated by a leaf spring. The leaf spring includes two opposed legs that extend from a floating intermediate portion of the leaf spring to the superior end plate and two opposed legs that extend from the floating intermediate portion to the inferior end plate. The disc replacement device is compact and provides freedom of movement along three axes, translational along the caudal/cranial axis, lateral bending and flexion/extension.