We studied the bone adaptation in a retrieved femur six years after
implantation of an Austin Moore prosthesis. Strains caused by loading of
the femoral head and greater trochanter were measured in this femur as well
as in the contralateral, normal femur before and immediately after
postmortem implantation of a prosthesis. Immediately after implantation the
strains were abnormally high, particularly in the calcar region. However,
six years after implantation all strains were close to normal. This was
found to be due to an increase in both the bone density and the bone area.
Changes were also noted in the structure of the osteons, particularly
adjacent to areas of endosteal compressive stress-transfer.