[The history and present status of bone densitometry]

Measurement of bone mass would be playing a major role in the field of research and clinical decision making of metabolic bone diseases, especially osteoporosis. As the magnitude of bone loss and the response to treatment are different from site to site throughout the entire skeleton, it is important to know which bone should be measured by which technique. Although values of BMD at various sites in the skeleton are significantly correlated, measurement at the actual site of fracture should be the most accurate way to predict fracture risk. New techniques and machines are now still under-developing and highly precise and site specific measurement of BMD may provide the predictive power needed for assessing fracture risk in individual subjects.