Abstract: Porous coatings on high-performance ceramics attempt to combine the mechanical and thermal characteristics, which fulfil stringent demands, of the substrate material with the advantageous properties of coating materials. The subsequent application of layers of this type to the pre-sintered substrate produces unsatisfactory results in several areas of use with regard to possible layer thickness, porosity and adhesion. According to the invention, a shaped body consisting of a sintered, inorganic material, whose surface comprises a porous layer is produced in such a way that the base body is first formed as a green body. A layer in the form of a suspension, also containing an inorganic material, is then applied to the surface or to one section of the surface of the base body. A predetermined fraction of a pore-forming substance is mixed with at least the material of said layer and the green body with its applied layer is subjected to the thermal treatments required for producing a monolithic sintered body.

Abstract: Porous coatings on high-performance ceramics attempt to combine the mechanical and thermal characteristics, which fulfil stringent demands, of the substrate material with the advantageous properties of coating materials. The subsequent application of layers of this type to the pre-sintered substrate produces unsatisfactory results in several areas of use with regard to possible layer thickness, porosity and adhesion. According to the invention, a shaped body consisting of a sintered, inorganic material, whose surface comprises a porous layer is produced in such a way that the base body is first formed as a green body. A layer in the form of a suspension, also containing an inorganic material, is then applied to thc surface or to one section of the surface of the base body. A predetermined fraction of a pore-forming substance is mixed with at least the material of said layer and the green body with its applied layer is subjected to the thermal treatments required for producing a monolithic sintered body.

Abstract: Joint prostheses, in which one joint partner is formed as a socket and the other joint partner is formed as a spherical head which is rotatably mounted in the socket, are known in particular as shoulder-joint and hip-joint prostheses. The force-fit connection, in particular conical jamming, is also used here as the connecting technique between metallic or ceramic spherical heads and the cone. A coupling element (6) is inserted between the cone (5) and the spherical head (3) of the force-fit connection (1). The elasticity and damping properties of the coupling element (6) can be predetermined by its porosity and the structure of its surface.

Abstract: The invention relates to a knee-joint endoprosthesis with a metallic femoral part (2) anchored in the femur that articulates with a tibial part anchored in the tibia bone, the articulating surface of the femoral part (2) being a ceramic structural member (3) that is connected to the femoral part (2) in mechanically stable manner. With a view to optimising the attachment of the ceramic structural member (3) to the femoral part (2), various possible solutions are proposed.

Abstract: An instrument for manipulating, detachably holding and placing an insert portion of a joint socket prosthesis into an outer shell of a said prosthesis. The instrument includes a handle and a holding tool. The holding tool includes two or more grasping claws which extend radially from the longitudinal axis of the handle over the insert, and serve to engage the insert to the holding tool. The handle is elongated and slideably positioned within a longitudinal bore or hole in the holding tool and typically includes a plunger. The insert is released when an operator causes the handle to slide within the holding tool towards the insert with sufficient force to disengage the insert from the grasping claws.

Abstract: According to the state of the art, the replacement of a basal finger joint is effected by, for example, interposition of soft part tissue or a distance piece, which does not, however, constitute a replacement joint. In joint prostheses with a metal-metal sliding combination, but in particular with a metal/polyethylene sliding combination, wear of the material can lead to osteolyses at the bone ends. Owing to the tact that the metal or plastic joint prostheses known from the state of the art are as a rule multipart, loosening of the individual components can occur, which shortens the service life of the implant.

Abstract: Prostheses with artificial joints have only a few metallic and ceramic materials whose compatibility with human or animal tissue has been established. These materials, however, cannot be combined with one another in any manner if a friction pairing occurs as a result, for example, in the case of artificial joints. With artificial joints, joint partners are required to have good mechanical properties as well as tribological properties. According to the invention, a sintered material is thus provided which is comprised of zircon oxide with an addition of 0.1 to 40 wt. % aluminum oxide. This sintered material enables an artificial joint of a prosthesis whose other ceramic materials are comprised of aluminum oxide or zircon oxide with the given proportions of aluminum oxide to be assembled with joint partners.

Abstract: A hip-joint socket of a hip-joint endoprosthesis is provided, in which the bearing shell of the socket that mounts the ball head of the shaft is made of a ceramic material. The bearing shell (2) of the hip-joint socket (1; 11), in the region of its surface (4) with which it is inserted into the hip bone, is covered with a coating (5; 15) that is made of a biocompatible metal or a biocompatible metal alloy.

Abstract: The invention relates to a hip joint prothesis having a metallic prothesis shell (1) with a cavity insert (2) having a spherical recess (3) and with an intermediate element (4) which is made of plastics and arranged between the prothesis shell (1) and the cavity insert (2). In order to avoid osteolysis, it is suggested that the intermediate element (4) consist of an upper portion (5) and a lower portion (6), that it be possible for upper portion (5) and lower portion (6) to be connected to each other, and that the cavity insert (2) be retained between upper portion (5) and lower portion (6).

Abstract: A knee-joint endoprosthesis includes a metallic femoral part (2) anchored in the femur that articulates with a tibial part anchored in the tibia bone, the articulating surface of the femoral part (2) being a ceramic structural member (3) that is connected to the femoral part (2) in a mechanically stable manner. The attachment of the ceramic structural member (3) to the femoral part (2), can be accomplished by using a conical clamping device, by use of a fixing screw, by shrinking, soldering or welding it on, or by vapor deposition or spray application.

Abstract: A ceramic socket or ceramic socket insert for a hip joint prosthesis is tested prior to implantation in a human body by subjecting the portions of the interior of the socket or socket insert to a load that generates stresses that are greater than the physiological load. This may be accomplished either by pressing a hemispherically-shaped deformable material such as polymer or plastic into the interior of the socket or socket insert or by exposing the interior of the socket or socket insert to a fluid under pressure. The interior of the socket or socket insert may be sealed off with a test punch that has a supply line for the fluid. To reduce the amount of fluid that is required, the test punch may have a bulge that projects into the interior of the socket or socket insert and leaves only a gap for the fluid.

Abstract: The invention relates to a knee-joint endoprosthesis with a femoral part anchored in the femur and a tibial plate connected to the tibia bone, on which tibial plate tibial parts are arranged by way of gliding surfaces, and preferably with meniscus elements disposed between the femoral part and the tibial parts. With a view to mechanically stable anchorage of the tibial part on the tibial plate that may optionally be subsequently released, even at the implanted joint, so that the tibial part can be exchanged, it is proposed that the tibial part or parts are detachably connected to the tibial plate by wedging, screwing and/or bracing.

Abstract: Joint prosthesis (1) with a cup-shaped supporting part (2) in whose interior a ceramic insert (3) is fastened by conical clamping. Clamping surface (6) of insert (3) runs at an angle (.alpha.) to clamping surface (7) of supporting part (2).

Abstract: Disclosed is a hip joint socket for insertion into bone tissue, having an outer metal shell and an inner antifriction liner. The antifriction liner is fixed in the metal shell by means of a taper lock. To safeguard the socket insert and antifriction liner against misalignment and separation, and enable a non-destructive removal of the liner and replacement thereof, the angle (.alpha.) of the taper lock of the liner in the shell is between 10.degree. and 25.degree..

Abstract: Disclosed is a hip-joint socket for insertion into bone tissue. The hip-joint socket has an outer metal shell and an inner antifriction shell, the contact surface of the antifriction shell in the metal shell being conical in shape. The antifriction liner lies upon the conical contact surface without self-locking and the antifriction liner is fixed in the metal shell by a retaining ring. The antifriction shell is thus protected against canting and drop-out but can be removed out of its seat nondestructively and replaced.

Abstract: The invention relates to a hip joint socket for insertion into bone tissue, with an outer metal shell and an inner ceramic shell, the ceramic shell being anchored in the metal shell. To reduce its size while simultaneously reducing the wall thickness of the ceramic shell the inside of the metal shell and the outside of the ceramic shell have a spherical shape accurately fitted to one another and means are disposed for equalizing the transmission of force between the ceramic shell and the metal shell.