Abstract: A medical drill for drilling holes in a bone or cartilage is formed with an end drill section. The end drill section has a specially formed drill tip at the distal end. The drill tip includes a flattened section which is located diametrically in relation to the central axis of the drill. The drill may be formed on the end of a router to provide a single loop to drill a pilot hole and then continue with the routing process. The drill section minimizes the heat created within the bone or cartilage.

Abstract: The present invention relates to a system for osteosynthesis at the vertebral column, in particular for stabilizing spinal segments including at least one rodlike connecting element (14) and at least two retaining units (12). Each retaining unit can be anchored to a spinal segment with a tuning-fork-shaped head, (15) the two limbs (16, 17) of which delimit an approximately U-shaped receptacle (18) for the connecting element (14) A clamping screw (19) can be screwed into the receptacle (18) to fix the connecting element (14) between the two limbs (16, 17) of the tuning-fork-shaped screw head (15) The floor (22) of the receptacle (18) has a concave shape to correspond to a swivel-bearing element (23) disposed between the floor (22) of the receptacle (18) and the connecting element (14) The element (24) has a bearing surface (24) faces the floor (22) of the receptacle (18) and, has a complementary convex curvature.

Abstract: The hemispherical acetabulum has a pin which projects from the cup of the acetabulum on an angle of 45.degree. relative to the polar axis. A sleeve which closes over the pin is rotatably mounted on the pin to facilitate twisting of the cup into a correct position when implanted in a pelvis. The sleeve is made of metal to preclude direct contact between the pin which may be made of plastic and the pelvis bone tissue.

Abstract: The shank is provided with a recess in the proximal medial region and a U-shaped wire mesh structure is secured within the recess. The wire mesh structure provides for an ingrowth of bone tissue at the medial narrow side of the shank and an absorption of shear micro movements between a bone and the implant. The mesh structure can be secured in place by rivets or by weld seams.

Abstract: The shaft portion of an artificial hip joint intended for cement-free anchoring in a femur which is generally rectangular in cross-section and is provided with outwardly projecting steps for direct transfer of axial forces between the shaft and the bone tissue, one half of the steps being transversely inclined with respect to the shaft axis with the other half of the steps inclined in the opposite direction by an equal amount to prevent rotation of the shaft as a result of the development of equal and opposite components of force.

Abstract: The thigh portion of an endoprosthesis for hip joints is provided with stepped projecting surfaces to distribute forces in the bone tissue.

Abstract: A rotary cutter for making the socket bed for a complete endoprosthesis is slidable on a guide rod, which rod is first inserted into a guide bore which has previously been made in the hip bone. The relative axial position of the cutter with respect to the rod indicates the depth of penetration of the cutter.

Abstract: A socket for hip joint prosthesis is secured to a cavity in the bone tissue by a series of radially arranged pegs which can be projected outwardly from the wall of the socket into the surrounding tissue by a central screw member which also has a self-tapping thread which also enters the tissue.