Postero-stabilised prosthesis with non-shifting femoral stud

Full knee prosthesis, a so-called postero-stabilised prosthesis, formed by a femoral part comprising two condyles between which extends a femoral stud of a cylindrical shape in order to define an opening, by a tibial part having a tibial plate, and by a tibial insert disposed between the femoral part and the tibial plate, a tibial stud projecting from a piece of the tibial insert, passing into the opening and coming into contact with the femoral stud from a given angle, in particular between about 20 and 30°, the tibial insert having concave upper surfaces in contact with the convex outer surfaces of the condyles, the contact defining a contact zone having a central point, is characterised in that the curve delimiting the transverse cross-section of the femoral stud is defined so that the central point of the contact zone undergoes a translation or recoil in the posterior direction for any angle of flexion between the said given angle up to 80 to 90°, and no longer undergoes any posterior recoil for any angle between about 80 to 90° and a maximum flexion of 120-130°.