Knee-joint endoprostheses

US4064568A · kind A · utility

Assignee

• Sanitatshaus Schuutt & Grundei

Inventors

• Hans Grundei · Lübeck, DE
• Wolfram Thomas · Winnenden, DE

Key dates

• Filing date: Nov 8, 1976
• Grant date: Dec 27, 1977
• Expiry date: Nov 8, 1996

Classification

• Technology area (CPC A): Human Necessities
• CPC primary: A61F2/385
• WIPO field: Medical technology
• WIPO sector: Instruments

Abstract

A knee-joint endoprosthesis comprising an upper and lower shank for attachment to the femur and tibia and provided with two pads which are yoked together across a central ridge. In such an endoprosthesis, the invention provides the improvement which consists in that a saddle-shaped ridge is provided with a fixed guiding cross-shaft which forms a free spigot on either side of said ridge and which lies off and to the rear of the center axis of said lower shank when the joint is in the extended position, in that two curved, hollowed-out bearing faces, and said supporting pads, which conform to said bearing faces in the extended position, diminish in width from front to rear as a result of said ridge becoming wider in the rearwards direction, in that said spigots engage with clearance in guide grooves in said supporting pads which extend approximately parallel to the lower faces of said pads and which open upwards at their rear ends, and in that the extension of the two sections of the joint is restricted by an abutment.