Intervertebral disc prosthesis for total replacement of an intervertebral disc within a lumbar and cervical spine, comprising
- an upper sliding partner adapted to firmly assemble to an upper vertebral body and a lower sliding partner adapted to firmly assemble to a lower vertebral body and, wherein said sliding partners articulate with each other via a sliding area and wherein
- a) a first of said upper/lower sliding partners has at a side opposite of a side for assembly with a vertebral body a convexity, wherein
- a. a radius of curvature of the convexity:
- i. in frontal and transversal view of the convexity is
- identical and
- results from rotation around a sectant of a segment of a first circle, wherein the segment corresponds to an entirety of the convexity, wherein the segment has a height and the height is less than the radius of the first circle, and
- ii. corresponds in sagittal view of the first sliding partner of the convexity to a radius of curvature of a second circle, wherein the radius of the second circle corresponds to the height of the segment of the first circle, wherein
- b. the convexity is enclosed by a surrounding edge, and
- b) a second of said upper/lower sliding partners has an inside with a concavity defined by a recess corresponding to the convexity of the first sliding partner, which is enclosed by an surrounding edge, and
- c) the surrounding edges of the upper and lower sliding partners, which extend between an outer rim and the convexity/concavity
- a. define, upon assembly, an outwardly opening aperture angle, with
- b. the aperture angles differing at least in a central frontal section compared to a central sagittal section due to different inclinations of the edges, to allow a maximal possible area of contact of the edges during terminal motion of the sliding partners, and
- c. the different inclinations of the edges seamlessly transiting,
- d. wherein, at equal aperture angles in a vertical section on both sides of the sliding areas, the inclinations of the edges are equal or different, and
- d) a motion angle is greater in a dorsoventral direction than in a laterolateral direction resulting from the different radii of curvature defined by the first and second circle, and
- e) maximal possible motion of the sliding partners toward each other is determined by
- a. radius of curvature of the convexity and height of the convexity relative to its surrounding edge, and
- b. design of each concavity with respect to its surrounding edge and shape with respect to the corresponding convexity, and
- c. the surrounding edges of the convexity and the concavity running at an incline or horizontally.