AN ABSENCE OF STRUCTURAL-CHANGES IN THE PROXIMAL FEMUR WITH OSTEOPOROSIS

The hypothesis that osteoporosis occurs not as a preferential loss of the tensile trabeculae but as a general loss of bone was tested by usi ng bone mineral densitometry and an indention test on dissected proxim al femora. As osteoporosis advanced a significantly correlated decreas e was found in both bone mineral density and mechanical properties bet ween the principal compressive and tensile trabeculae. The decrease co rrelated with a decrease in the Singh index. These findings led to the conclusion that a sequential bone loss from the tensile trabeculae to the compressive ones did not occur as Singh reported, but instead a g eneralized loss of bone mineral in both the tensile and compressive tr abeculae supervened. The structural changes, on which the grading syst em by Singh was based, were not observed in the proximal femur affecte d by osteoporosis.