Intervertebral disc prosthesis

#The present invention relates to an intervertebral disk prosthesis which is placed between the upper end plate and the lower end plate of the vertebral bodies of the overlying and underlying vertebrae of a spinal column.

#German patent DE 2263842 discloses an intervertebral disk prosthesis comprising an upper plate and a lower plate which are provided respectively on their inner face with a cavity in the shape of a portion of a sphere and with a spherical core placed between the plates and collaborating with the cavities that have the same profile.

#The upper plate and the lower plate are joined together and around the spherical core by a peripheral element made of a soft material such as plastic.

#The description which will follow with reference to the appended drawings which are given by way of nonlimiting examples will allow for a better understanding of the invention, of the characteristics it has and of the advantages it is likely to afford:

#FIG. 1 is an exploded perspective view illustrating the intervertebral disk prosthesis according to the present invention.

#FIG. 2 is a view in section showing the intervertebral disk prosthesis according to the present invention.

#FIGS. 1 and 3 depict an intervertebral disk prosthesis 1 comprising two plates, an upper plate 2 and a lower plate 3, a central core 4 and an annular element 5, so as to restore mobility between the overlying and underlying levels of two adjacent vertebrae of a spinal column.

#Each plate, upper 2 and lower 3, has an outer face 6 integral with teeth 7 to allow said plates to become anchored in, respectively, the upper and lower end plates of the vertebral bodies of the overlying and underlying vertebrae.

#Each plate, upper 2 and lower 3, has, on the opposite side to its outer face 6, an inner face 6 which has a spherical cavity 9 delimited by a circular rim 10 which is raised with respect to the horizontal plane of the face 8.