Patent ID: 6682562
Filing Date: 2004-01-27
Classification: A61F

Abstract:
An intervertebral disk prosthesis comprising an upper plate (2) and a lower plate (3) which are adopted to be anchored respectively to the upper end plate and the lower end plate of the vertebral bodies of the overlying and underlying vertebrae of a spinal column and a central core (4) placed between the two plates (2, 3) which has an upper spherical cap (13) and a lower spherical cap (14) collaborating respectively with spherical cavities (9) formed in said upper and lower plates, said disk further comprising an annular element (5) made of a viscoelastic material which is centered around the core (4) and which comes into contact with bosses (12) provided on a inner face (8) of the upper plate (2) and of the lower plate (3) so as to restrict and control the movements in bending, inclination and rotation of the upper plate (2) and of the lower plate (3) one with respect to the other and about the core (4), as to ensure stability in the positioning of the core (4) between the two plates (2, 3), and as to avoid fibrous deposits inside the prosthesis (1).