Patent ID: 7575599
Filing Date: 2009-08-18
Classification: A61F,Y10T

Abstract:
1. A prosthetic disc for insertion between adjacent vertebrae, the prosthetic disc comprising: a core having upper and lower curved surfaces, wherein each of the curved surfaces comprises a metal; upper and lower plates, each plate having an outer surface which engages a vertebra and a metallic inner curved surface which is shaped to slide and translate over one of the curved metallic surfaces of the core, wherein a center of rotation of the core is free to move relative to the upper and lower plates; a peripheral restraining structure on at least one of the upper plate and the lower plate to hold the core against a curved surface of at least one of the plates during sliding movement of the plates over the core, the peripheral restraining structure comprising an annular structure extending over at least a portion of the periphery of the core and a ring structure on one of the upper and lower plates, which ring structure engages and retains the annular structure, wherein the restraining structure is adapted to contact an opposing plate to limit relative inclination of the plates during sliding movement of the plates over the core.