Femoral part of a hip joint endoprosthesis

Abstract

Abstract 1. Upper thigh part of a hip-joint endoprosthesis, consisting of a fibre-strengthened, curved endoprosthesis shaft (6) with unidirectional or partially unidirectional arrangement of the fibres (8) in the longitudinal direction of the shaft, which comprises an upper shaft part (7), a sharply curved central part and a lower shaft part (11) which tapers toward the free end, and of an endoprosthesis head (1) consisting of ball (2) and collar section (3), in which the endoprosthesis shaft (6) which is firmly connected with the endoprosthesis head (1) does not have a collar, and in which the head axis (A) given by the perpendicular line through the central point (5) of the ball onto the base (4) of the head, and the upper shaft axis (B), given by the principal orientation of the fibres (8) in the upper shaft part (7) and the central point (9) of the virtual intersecting plane (4a) through the shaft (6) determined through the basal plane of the head, are not identical, in which the head axis (A) and the upper shaft axis (B) form an acute angle (alpha), characterized in that the endoprosthesis head (1) consists of polycrystalline, isotropic, ceramic material, that the upper shaft part (7) is constructed substantially conically and protrudes into the endoprosthesis head (1) up into the ball (2), and that the angle (beta) formed between the head axis (A) and the lower shaft axis (C), given by the principal orientation of the fibres (8) in the lower shaft part (11), is greater than the angle (gamma) formed between the upper shaft axis (B) and the lower shaft axis (C).

Inventors

• 👤 K. J. Prof. Dr. Hüttinger
• 👤 H. Dr. Brückmann

Bibliographic Details