Inventors:
Henry A. Finn - Chicago IL
Assignee:
Arch Development Corporation - Chicago IL
International Classification:
A61F 238
Abstract:
A constrained prosthetic knee for surgical replacement of a dysfunctional knee includes a tibial platform, a movable bearing element, a hinge portion, and a femoral component.
In one embodiment of the invention, the femoral component is typically constructed of a cobalt-chromium or titanium alloy and includes an upward extension for securing the femoral component to the femur. The femoral component, in this embodiment, includes a convex curve which rotatably and/or slidably engages the movable bearing, typically constructed of high molecular weight polyethylene. The superior surface of the bearing element is designed to congruently slidably engage the inferior surface of the curved portion of the femoral component. The inferior surface of the femoral component is generally convex with a radius of curvature matching the superior surface of the bearing element. The inferior surface of the femoral component may have more than one radii of curvature at different points along the convex surface.