Knee joint prosthesis

US4213209A · kind A · utility

Assignee

• New York Society for the Relief of the Ruptured and Crippled · US

Inventors

• John N. Insall · New York, US
• Peter S. Walker · Ridgewood, US

Key dates

• Filing date: May 22, 1978
• Grant date: Jul 22, 1980
• Expiry date: May 22, 1998

Classification

• Technology area (CPC A): Human Necessities
• CPC primary: A61F2/3886
• WIPO field: Medical technology
• WIPO sector: Instruments

Abstract

A knee joint prosthesis comprises a femoral component having laterally spaced-apart condylar portions shaped to match generally the shapes of the condylar surfaces of the femur and a tibial component having a plate-like platform portion which includes laterally spaced-apart concavities in the external surface, each of which receives and supports one of the condylar portions of the femoral component in all positions of the leg. The femoral component has a box-like intercondylar portion interconnecting the condylar portions and defining an intercondylar recess which receives a post that extends upwardly from the tibial component. At and near full extension of the leg, any tendency for posterial dislocation of the femur results in engagement between the anterior surfaces of the post and recess to prevent posterial dislocation of the femoral component relative to the tibial component. At leg flexions approaching full flexure, the posterior surface of the recess engages the posterior surface of the post in the event of a tendency toward anterial dislocation of the femur, thereby preventing anterial dislocation. Large antero-posterior movements and dislocation are prevented in all leg po…