Patent ID: 7198643
Filing Date: 2007-04-03
Classification: A61B,A61F,Y10S

Abstract:
1. An apparatus for replacing at least a portion of an intervertebral disc in a spinal column, comprising: a first member having a first vertebral contact surface for engagement with an endplate of a first vertebral bone in the spinal column, and having a first articulation surface that is a single toroidal saddle shaped surface including a first concave arc extending from the leading end to the trailing end of the first articulation surface and a first convex arc extending from the first lateral end to the second lateral end of the first articulation surface; and a second member having a second vertebral contact surface for engagement with an endplate of a second vertebral bone in the spinal column, and having a second articulation surface that is a single toroidal saddle shaped surface including a second convex arc extending from the leading end to the trailing end of the second articulation surface and a second concave arc extending first lateral end to the second lateral end of the second articulation surface, wherein the first concave arc has a radius that is greater than the radius of the second convex arc and the second concave arc has a radius that is greater than the radius of the first convex arc, wherein: an intervertebral disc space is defined substantially between the first and second endplates of the first and second vertebral bones, and the first and second articulation surfaces are sized and shaped to engage one another when the first and second members are disposed in the intervertebral disc space to enable the first and second vertebral bones to articulate in at least one of flexion, extension and lateral bending.