Shaft for hip joint prosthesis - has upper part with open cell surface structure and lower part with smooth surface

摘要

A hip joint prosthesis has a shaft with a collar (6) and a conical upper end piece (7) for fitting in a ball end. The proximal part of the shaft immediately below the collar has an open cell surface structure whilst the distal part has a smooth surface structure. The open cell surface structure extends further towards the distal end on the inner side of the shaft than it does on the outer side of the shaft. The smooth surface part (10) extends upwards inside the open cell surface part (13). ADVANTAGE - The open cell structure enables the bone to grow into the shaft.