New York Society for the Ruptured and Crippled Maintaining the Hospital for Special Surgery

Mathys Medical Ltd.

Donald L Bartel

Joseph David Lipman

Timothy M Wright

Robert N Hotchkiss

Darrick Lo

Mark P Figgie

Russell F Warren

Daniel Delfosse

Christoph Fankhauser

Walter Supper

Thomas L Wickiewicz

Frank Hoffman

Apparatus and methods for total elbow replacement are provided to allow a surgeon to intraoperatively select a linked or unlinked constraint by utilizing a connection located on the body of the ulnar and/or humeral stem. Additional modularity also allows the selection of a cemented or cementless stem as described herein. The modularity and adjustability provides a number of advantages.

Elbow replacement apparatus and methods

A knee joint prosthesis includes a femoral component having a first condylar bearing surface and a second condylar bearing surface. Each of the first and second condylar bearing surfaces has a cross-section in a coronal plane that exhibits at least two different radii. The prosthesis also includes a tibial component and an insert component associated with the tibial component. The insert component has bearing surfaces that are complementary to the first and second condylar bearing surfaces, wherein a contact point is established between the bearing surfaces of the insert component and the first and second condylar bearing surface. In accordance with the present invention and as a result of the above construction, varus and valgus rotation of the femoral component relative to the insert component causes the contact point to move laterally as the knee is rotated. By shifting the contact pointy laterally/outwardly, the knee stability (i.e., stiffness) gradually increased.

Constrained condylar knee device

A prosthetic joint according to the present invention includes a first implant component for attachment to a first bone and a second implant component for attachment to a second bone. The first implant component has a condylar portion that includes first and second condylar bearing surfaces and similarly, the second implant component has bearing surfaces that receive and are complementary to the first and second condylar bearing surfaces. Each of the first and second condylar bearing surfaces and each of the bearing surfaces of the second implant component has a cross-section in a coronal plane that exhibits two different radii and a contact point is established between the first and second condylar bearing surfaces and the bearing surfaces of the second implant component. The bearing surfaces of the respective implant components are configured such that varus and valgus rotation of the first implant component relative to the second implant component causes the contact point to move outwardly.

Prosthetic condylar joints with articulating bearing surfaces having a translating contact point during rotation thereof

A prosthesis for repairing a knee is made with an insert sandwiched between a femoral component and a tibial tray. The parts are shaped so that both the femoral component and the tibial tray will slidingly interface with the insert during motion of the knee. At regions where the femoral component interfaces with the insert during extension and during an initial range of flexion of the knee, the femoral component's radius of curvature (R) for flexion rotation is larger than its radius of curvature (R) for varus/valgus rotation. In a preferred embodiment, the surface of the tibial tray is convex and spherically curved, and the insert is free to move in both the posterior-anterior direction and the medial-lateral direction with respect to the tibial tray.

Self-aligning knee prosthesis

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Ithaca, NY, United States of America

Donald L Bartel