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tude of external forces applied to it. The presence of a rigid prosthetic stem exerts a stress shielding effect on the proximal femur. Experimental stress analysis of the proximal femur both with and with-out a cemented intra-medullary stem has shown stress reduction of up to 60 % in the surrounding bone of the proximal part of the implanted stem (10). This leads to significant loss of bone stock in the proximal femur. In an endeavour to retain the physiological stress pattern and bone stock as far as possible, the thrust plate prosthesis (TPP) was developed by Jacob and Huggler (10). The principle of the thrust plate prosthesis is to transfer the resulting forces from the hip joint via a thrust plate directly to the femoral neck and above all to the cortical bone of the calcar (12). This force transfer is as close to physiological as possible, Acta Orthopædica Belgica, Vol. 71- 2- 2005 Early results with the thrust plate prosthesis in young patients with osteoarthritis of the hi