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Hjs Gelenk System Gmbh

Dietmar Kubein-Meesenburg

Hans Naegerl

Hans Nagerl

Joachim Theusner

Peter Adam

Dankmar Ihlow

An artificial joint (), particularly for replacing a talocrural joint, including a first primary joint surface () that forms an articular fossa () particularly for replacing the tibia composed of concave curvatures extending parallel to a primary function plane of the joint (), which corresponds to the sagittal plane, and a second primary joint surface () which cooperates with the first primary joint surface () as a component of a condoyle () that replaces the talus and has convex curvatures () on the primary function plane that are adapted to the first primary joint surface (). To achieve high stress resistance and optimal joint mobility, depending on the position of the joint, the radii of the curvatures () are calculated such that the differential amounts arising between the corresponding radii of the first and second primary joint surfaces () in an ascending angular position (V) relative to a descending angular position and also simultaneously between a medial face () and a lateral face () of the joint () deviate from one another.

Artificial joint

An artificial joint () suitable for use as an endoprosthesis for a human knee joint, having a first joint compartment () formed by a first condyle () and a first socket () and a second joint compartment () formed by a second condyle () and a second socket (). The contact surfaces (C) of the respective joint compartments () are offset in the main functional plane. To further improve the characteristics of the artificial joint (), the contact surfaces (C) of the two joint compartments () are sloped as a function of the flexion angle such that the surface normals () of the contact surfaces (C) have a common point of intersection at every flexion angle. This arrangement of the contact surfaces (C) achieves self-stabilization of the joint () both when a rotary motion or torsion and when lateral forces are introduced.

Artificial joint particularly suitable for use as an endoprosthesis for a human knee joint

An abrading body ( ) for treating tooth crowding, which can be introduced into interdental spaces ( ) between teeth ( ) and is provided with oppositely disposed working or abrading surfaces ( ) on both sides thereof and a shaft for attachment to a reciprocating drive mechanism ( ). The abrading body ( ) can be introduced vertically between the teeth ( ), i.e., in the longitudinal direction thereof, and is designed to carry out an abrading movement in this direction. The abrading surface ( ) is formed with a convex cross-sectional configuration. The opposite abrading surface ( ) is formed with a concave cross-sectional configuration. The radius (R ) of the convex abrading surface ( ) is greater than the radius (R ) of the concave abrading surface ( ). An advantageous interdental contact in the form of an overlapping, dimeric, arcuate chain of teeth can be created by introducing concave and convex contact surfaces on adjacent teeth using the tooth abrading body ( ) of the invention.

Dental abrading body for treating tooth crowding

An exoprosthesis/orthosis for the human knee-joint comprised of an upper leg part ( ) which can be connected to the human upper leg, and a lower leg part ( ) which can be connected to the human lower leg. Both leg parts ( ) are connected at least via a joint which constructs a joint with two joint axes (M , M ), 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 ( ) with regard to the momentary joint axis of said leg parts, whereby curved teeth ( ) are constructed on the upper leg part ( ) and on the lower leg part ( ). The teeth interact similar to sprocket gearing in the movement functional area of the joint ( ), whereby the curved teeth coincide with the polodes (t, f) of both leg parts ( ) in the movement functional area.

Exoprosthesis for the human knee-joint

An artificial condyle (,) for use in a human hip joint in which the condyle has a spherical joint shell (,) which has a radius of curvature R,and a curvature midpoint M,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 (,) is designed as a sphere such that when it is inserted in the shell (,), in a longitudinal plane X&mdash;X passing through the midpoint M,, a radius R,&equals;R,is formed which has a midpoint M,coinciding with M,. A transverse plane Y&mdash;Y perpendicular to the longitudinal plane X&mdash;X has, passing through the midpoint M,, a radius R,<R,having the midpoint M,. In the transverse plane Y&mdash;Y a stable dimeric joint chain is formed, with which the joint axis path of the midpoints M,and M,has a joint path radius R&equals;R,&minus;R,.

Artificial condyle for the human hip joint

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 (L,) of one of the articulation faces is part of an elliptical section contour of a first cylinder (,) or cone having the cylinder radius (R,) or the cone angle (&agr;1). The other contact line (L,) takes the form of a counter track of a second cylinder (,) or second cone having the cylinder radius (R,) or the cone angle (&agr;2) and rolling and/or sliding on the first cylinder (,) or first cone. The articulation faces comprise control faces (F,, F,) formed from a plurality of straight contact lines (B). On one side, these control faces (F,, F,) adjoin the contact lines (L,, L,) opposite one another, and each of the contact lines is the connection line between an instantaneous contact point (K) of the contact lines (L,, L,) and an instantaneous common point (Q) or the instantaneous pole of the respective movement systems in a reference plane (X, Y) or a reference sphere in the moved/unmoved system.

Artificial joint, in particular endoprosthesis for replacing natural joints

Artificial joint, in particular an endoprothesis for the human knee joint, consisting of at least two joint parts moving with respect to each other, a joint head and a joint base, with toroidal joint surfaces, that have function surfaces with differing circular intersection contours in mutually perpendicular planes--a longitudinal plane and a transverse plane--whereby the curve ratios of the function surfaces are defined in each of the planes as either convex-convex, convex-concave, or concave-concave, and the joint geometry of the function areas to each other in each of the two planes is determined by a link chain with two link axes (dimeric link chain), which proceed through the rotation centers of the function areas with the radii of the attendant intersection contours, respectively.

Exoprosthesis for the human knee joint

Artificial joint to replace the human patella

Artificial joint, in particular an endoprothesis for the human knee joint, consisting of at least two joint parts moving with respect to each other, a joint head and a joint base, with toroidal joint surfaces, that have function surfaces with differing circular intersection contours in mutually perpendicular planes--a longitudinal plane and a transverse plane--whereby the curve ratios of the function surfaces are defined in each of the planes as either convex--convex, convex-concave, or concave--concave, and the joint geometry of the function areas to each other in each of the two planes is determined by a link chain with two link axes (dimeric link chain), which proceed through the rotation centers of the function areas with the radii of the attendant intersection contours, respectively.

The invention at hand concerns an artificial joint, in particular an endoprosthesis for a human shoulder joint, consisting of two parts, a joint head (3) and a joint pan (2) with spherical joint surfaces moving relative to one another. The bending conditions of the functional surfaces (5,7) are convex-concave in the frontal plane as well as in the perpendicular transverse plane. The joint geometry of the functional surfaces towards each other in both planes is determined through a dimeric joint chain which runs through the rotation centers of the functional surfaces of each of the intersection contours. The joint head (3) and the joint pan (2) are arranged in relation to their functional surfaces such that in their position corresponding to the rest position of the arm in a dangling state the functional surfaces (5,7) have the same radius of curvature in the contact area (8) on both sides in the frontal plane with a linear contact of the functional surfaces (5,7), and such that a roll-off area (9) adjoins, in which the radii R.sub.P1, R.sub.K1 of both functional surfaces (5,7) are selected such that a circumferentially widening gap section covers the area between both joint parts (2,3).

Artificial joint as an endoprosthesis for the human shoulder joint

Artificial joint for replacing human joints in particular, consisting of at least two joint parts with spherical functional surfaces that can move relative to each other. 2 The curvature relationships of the functional surfaces having a circular cross-sectional contour are convex/convex, convex/concave or concave/concave relative to each other, and the geometric design of the joint is determined by a joint chain with two joint axes running through the centers of rotation M.sub.1 and M.sub.2 of the functional surfaces with radii R.sub.1 and R.sub.2, where R.sub.1 is the radius of the circular cross-sectional contour of the functional surface with center of rotation M.sub.1, and R.sub.2 is the radius of the circular cross-sectional contour of the functional surface with center of rotation M.sub.2.

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Goettingen, Germany

Dietmar Kubein-Meesenburg