Development of periprosthetic bone mass density around the cementless Metha (R) short hip stem during three year follow up-a prospective radiological and clinical study

摘要

Purpose The purpose of this study was to check the concept of the cementless Metha (R) short hip stem in order to find out whether proximal physiological load transfer can be achieved. Methods Fourty-three patients were included. Epidemiological factors were established. The Harris Hip Score was determined and measurement of bone mass density as well as osteodensitometric and radiological measurements was carried out pre-operatively, post-operatively, and after six, 12, 24, and 36 months. Results Harris Hip Score improved from 55.9 +/- 12.4 pre-operatively to 94.8 +/- 8.2 after 36 months (p < 0.001). After initial reduction of bone density in zones 1 and 7 up to six months post-operatively, there was a steady approximation of bone density to the initial values (p < 0.05). Conclusion The Metha (R) short hip stem shows good clinical results. Furthermore, there is an increase of bone density in the proximal zones 1 and 7 between six and 36 months serving as a sign of physiological load transfer.