Abstract: An exoprosthesis/orthosis for the human knee-joint comprised of an upper leg part (1) which can be connected to the human upper leg, and a lower leg part (2) which can be connected to the human lower leg. Both leg parts (1, 2) are connected at least via a joint which constructs a joint with two joint axes (MU, M0), i.e. a so-called dimeric joint chain, which are connected such that they carry out a forced movement. A polode (movement or rest polode) is assigned to each respective leg part (1, 2) with regard to the momentary joint axis of said leg parts, whereby curved teeth (5, 7) are constructed on the upper leg part (1) and on the lower leg part (2). The teeth interact similar to sprocket gearing in the movement functional area of the joint (3), whereby the curved teeth coincide with the polodes (t, f) of both leg parts (1, 2) in the movement functional area.

Abstract: An artificial condyle (2) for use in a human hip joint in which the condyle has a spherical joint shell (1) which has a radius of curvature R1 and a curvature midpoint M1 and in cross-section a circular concave section contour. A functional surface which is convex at least in a region which articulates in the joint shell (1) is designed as a sphere such that when it is inserted in the shell (2), in a longitudinal plane X—X passing through the midpoint M1, a radius RK1=R1 is formed which has a midpoint MK1 coinciding with M1. A transverse plane Y—Y perpendicular to the longitudinal plane X—X has, passing through the midpoint MK1, a radius RK2<RK1 having the midpoint MK2. In the transverse plane Y—Y a stable dimeric joint chain is formed, with which the joint axis path of the midpoints MK1 and MK2 has a joint path radius R=RK1−RK2.

Abstract: The invention concerns an artificial joint, in particular an endoprosthesis for replacing natural joints, comprising at least two artificial joint parts with curved articulation faces, a curved contact line being formed on each of the articulation faces. The curved contact line (L1) of one of the articulation faces is part of an elliptical section contour of a first cylinder (1) or cone having the cylinder radius (R1) or the cone angle (&agr;1). The other contact line (L2) takes the form of a counter track of a second cylinder (2) or second cone having the cylinder radius (R2) or the cone angle (&agr;2) and rolling and/or sliding on the first cylinder (1) or first cone. The articulation faces comprise control faces (F1, F2) formed from a plurality of straight contact lines (B).