Abstract: Milling tool for emptying the femoral medullary space, while creating a space for the shaft of a hip prosthesis, which comprises a flexible core and a plurality of conical, rotationally symmetrical milling segments, mounted in superimposed manner on the core and provided with a central through-bore, the milling segments being so connected to the core and/or the milling segments adjacent thereto, that a rotational force applied to the core and/or the upper segment is transferred to the individual milling segments, as well as a hip prosthesis with a conically directed shaft and a ball mounted on the proximal end of the shaft and which comprises a flexible core, a plurality of conical, rotationally symmetrically segments, mounted in superimposed manner on the core and provided with a central through-bore and a device for tensioning the core to bring a stiffening of the shaft formed from the individual segments.

Abstract: Milling tool for emptying the femoral medullary space, while creating a space for the shaft of a hip prosthesis, which comprises a flexible core (10) and a plurality of conical, rotationally symmetrical milling segments (12), mounted in superimposed manner on the core (10) and provided with a central through-bore, the milling segments (12) being so connected to the core (10) and/or the milling segments (12) adjacent thereto, that a rotational force applied to the core (10) and/or the upper segment (12) is transferred to the individual milling segments (12), as well as a hip prosthesis with a conically directed shaft and a ball (16) mounted on the proximal end of the shaft and which comprises a flexible core (10), a plurality of conical, rotationally symmetrical segments (12), mounted in superimposed manner on the core (10) and provided with a central through-bore and a device (14) for tensioning the core (10) to bring about a stiffening of the shaft formed from the individual segments (12).

Abstract: Milling tool for emptying the femoral medullary space, whilst creating a space for the shaft of a hip prosthesis, which comprises a flexible core and a plurality of conical, rotationally symmetrical milling segments, mounted in superimposed manner on the core and provided with a central through-bore, the milling segments being so connected to the core and/or the milling segments adjacent thereto, that a rotational force applied to the core and/or the upper segment is transferred to the individual milling segments, as well as a hip prosthesis with a conically directed shaft and a ball mounted on the proximal end of the shaft and which comprises a flexible core, a plurality of conical, rotationally symmetrically segments, mounted in superimposed manner on the core and provided with a central through-bore and a device for tensioning the core to bring a stiffening of the shaft formed from the individual segments.

Abstract: In an endoprosthesis including a ball-and-socket joint, the ball and a socket insert having a spherical surface are made of ceramic material. The opening edge of the socket is covered by a polyethylene protecting ring whose opening side is covered by a covering ring made of a resilient material. The inner edge of the protecting ring is appropriately covered by the protecting. The socket, the ceramic insert, the protective ring and the covering ring are configured so as to permit sliding of a ball seated in the socket and configured to conform to the spherical surface of said ceramic insert out of the endoprosthesis.