Kit of parts for a modular femur head prosthesis, in particular, a reoperation prosthesis, and a femur head prosthesis from such a kit of parts

The kit of parts comprises a distal shaft part (2) and a neck part (3) which can be equipped with a joint ball (10), with the neck part being supported on the shaft part (2) by approximately rectangular shaped supporting surfaces (2c) and (3c) positioned transverse to the longitudinal axis (L) of the shaft part (2). The shaft part (2) and the neck part (3) are provided with prismatic guide surfaces (2d) and (3d) brought together in a form-fit and orientated parallel to the longitudinal axis (L), and are rigidly connected to each other by an extensible shaft screw (11) which can be elastically prestressed to carry a predetermined bending moment. The guide surfaces (2d) and (3d) are formed at a spigot extension (2b) of the shaft part (2) and at a complementary recess (3b) of the neck part (3), respectively. This design allows a form-fitted centering and accurate positioning of the neck part (3) on the shaft part (2) by the guide surfaces (2d, 3d) and, independent therefrom, a force-locked connection between the neck part (3) and the shaft part (2) by way of the supporting surfaces (2c, 3c) which can be clamped against one another with the bias force of the extensible shaft screw (11).