Self-aligning knee prosthesis

US7105027B2 · kind B2 · utility

Assignee

• Mathys Medical Ltd. · CH

Inventors

• Joseph D. Lipman · New York, US
• Russell Warren · Greenwich, US
• Thomas L. Wickiewicz · New York, US
• Timothy M. Wright · New York, US
• Donald L. Bartel · Freeville, US
• Frank Hans Hoffman · Rosenheim, DE
• Christoph Fankhauser · Solothurn, CH
• Daniel Delfosse · Jegenstorf, CH
• Walter Supper · Bettlach, CH

Key dates

• Filing date: Jan 31, 2003
• Grant date: Sep 12, 2006
• Expiry date: Jun 10, 2023

Classification

• Technology area (CPC A): Human Necessities
• CPC primary: A61F2310/00179
• WIPO field: Medical technology
• WIPO sector: Instruments

Abstract

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 (R1) for flexion rotation is larger than its radius of curvature (R3) 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.