The prosthesis has a longitudinally elongated rod (1) with two ends and a joint unit (2) which is arranged at the latter end of the rod. The rod and the joint unit are coupled with complementary cone connectors (18,29) over a plug connection. A longitudinal adjusting unit (3) is designed in modular shape and is provided with the complementary cone connectors at its proximal and distal ends. An independent claim is also included for a prosthesis system with a shaft element.
