System for determining the position of a knee prosthesis

Abstract

The invention concerns a system for determining the ideal theoretical position of a knee prosthesis comprising, for determining the position of a tibial prosthesis, means for: determining the shape of the tibia proximal part and its position relative to the centre of the ankle joint; determining a high point of the tibial plateau; calculating the position of the ankle, the orientation and the size relative to the tibia of the tibial prosthesis and the section plane corresponding to the tibial prosthesis taking into account the following parameters: the perpendicular to the section plane passing through the centre of the prosthesis also passes through the centre of the ankle joint; the section plane is at a distance from said high point equal to the height of the prosthesis to be fixed; the large end of the prosthesis is centred on the large end of the tibia cross-section in the section plane; the front edge of the small end of the prosthesis is at a predetermined distance from the small end of the tibia cross-section in the section plane; and determining the orientation in the section plane of the prosthesis such that the large end of the prosthesis should be parallel to the horizontal axis of the knee.

Dependencies are inferred from the claim text.