Abstract: A saddle-type prosthesis for replacement of a hip joint; includes a shank assembly for engagement in a femur, a saddle-shaped head having a seat to form a bearing area for engagement by a portion of a pelvic bone, and a mounting for so coupling the saddle-shaped head to the shank assembly as to permit a pivoting of the saddle-shaped head relative to the shank assembly about at least two predetermined axes for rotation with at least two degrees of freedom wherein one of the predetermined axes is positioned above the bearing area of the saddle-shaped head.

Abstract: A knee joint prosthesis with a tibial component, a femoral component and a hinge which connects the two components and defines a pivot axis at a fixed distance from both components. The planes of the axes of shanks of the two components are located at selected distances from each other and from the pivot axis, and the pivot axis is placed nearer to the rear portions than to the front portions of the two components. This reduces the need for resection of affected bones and enhances the transfer of forces as well as the stability of the prosthesis.

Abstract: A knee joint prosthesis kit which is composed of a femoral component having a housing and a shank implantable in a femur, a first tibial component having a first hinge leaf and a shank implantable in a tibia, a second tibial component having a second hinge leaf and a shank implantable in a tibia, and a pintle which can pivotally connect the housing of the femoral component with that tibial component whose leaf is inserted into the housing. This enables the femoral component and the first tibial component to pivot relative to each other abut a first axis which is normal or nearly normal to the shanks of the coupled components so that the resulting prosthesis can serve as a flexion type prosthesis.

Abstract: A hip prosthesis wherein a saddle-shaped head has a seat flanked by two horns and engageable with the surface bounding a recess in the lower part of a damaged pelvic bone. The head is rotatably or rigidly secured to a substantially S-shaped adapter which, in turn, is rotatably or non-rotatably secured to the adjacent end of a shank that is implantable in the cavity of a femur. One or more distancing rings can be inserted between the adapter and the head.

Abstract: An internal prosthesis for the partial or total replacement of a bone such as a femur has a rod-like bridging member which spans the major part of the gap between two joints. An abutment member is mounted at either end of the bridging member and each of the abutment members engages a bone adjacent that which is to be partially or totally replaced. Each of the abutment members may constitute part of an artificial joint. The bridging member and/or the abutment members are adjustable so that the prosthesis may be fitted to the particular physical characteristics of a patient. To this end, the bridging member may be composed of sections for the purpose of length adjustment. The abutment members may be rotatable relative to one another and to the bridging member about the longitudinal axis of the latter in order that the abutment members may assume a relative angular orientation best suited to the characteristics of the patient.

Abstract: A knee joint prosthesis wherein a first component which is partially embedded in the femur carries a pivotably mounted tubular guide for a pin-shaped second guide mounted on a second component which is partially embedded in the tibia. The second guide is rotatable and reciprocable in the tubular guide, and the extent of the reciprocatory movement is limited by two abutments one of which is mounted on the first component and the other of which is mounted on the second component.

Abstract: A prosthesis which is particularly well-suited for use in the region of the hip joint has a shaft which carries a bearing at one end. The bearing has a rim at its junction with the shaft. The end of the bearing opposite the rim has a saddle-shaped portion including a pair of protrusions which flank a depression. The depression has a pair of bearing surfaces separated by a protuberance which is formed in the depression and extends from one of the protrusions to the other. The prosthesis is installed at a hip joint by inserting the shaft into the end of the femur nearest the pelvis. The shaft is pushed into the femur until the rim on the bearing contacts the end of the femur. One of the protrusions is passed through an opening in the wall of the pelvis so that the wall is received in the depression of the bearing. The wall is contoured so as to conform to the shape of the depression and the protuberance therein and rests on the surface of the protuberance as well as the bearing surfaces of the depression.

Abstract: A prosthesis for the knee joint has a tibial component and a femoral component. No mechanical connection exists between these components. The tibial component includes a shaft which carries a platform and is received in the cavity of the tibia so as to position the tibial component. The platform supports a bearing element which engages the femoral component and, in addition, a projection is mounted on the platform and extends towards the femoral component. The femoral component includes a shaft which carries a hinge and is received in the cavity of the femur to position the femoral component. The hinge, which defines a pivot axis for bending of the knee, comprises a hinge pin having a recess which faces the tibial component. The projection is slidably received in the recess and defines a rotational axis about which limited rotation of the tibial component relative to the femoral component may take place. In addition, the projection maintains the hinge pin in requisite position.

Abstract: A knee joint endoprosthesis includes a femoral component, a tibial component and a slide bearing providing for relative pivotal movement between the components and formed of a femoral bearing half carried by the femoral component and a tibial bearing half carried by the tibial component. The bearing halves are arranged for being pressed to one another while free from being connected to one another. There is further provided an arrangement for cardanically guiding the bearing halves with respect to one another with degrees of freedom in horizontal and vertical directions.

Abstract: An ultrasonic tool is used for dissolving the bond between nested components cemented together by a plastic layer. The vibrating tool causes softening of at least portions of the plastic layer, and subsequently the components can be readily detached from one another.