Non-invasive methods for quantitating bone loss of aging.

The clinical utility of bone mass measurements has been the subject of considerable debate. The determination of whether a measurement has utility in clinical practice is difficult, but several elements must be present. First, the measurement must be predictive of clinical outcomes. Two recent studies have shown that bone mass measurements predict the incidence of both nonspine and vertebral body fractures. A second necessary element is the availability of therapeutic options which would be based on these measurements. The effectiveness of estrogen replacement therapy in preventing bone loss and subsequent fractures is well documented. It is also possible that alterations in glucocorticoid therapy or treatment of hyperparathyroidism might be based on bone measurements. Finally, it should be clear that the information available through bone mass measurements would not be otherwise obtainable. Researchers have yet to demonstrate that other risk fractures are adequate substitutes either in the prediction of bone mass or in the estimations of fracture risk. Although it is not yet clear that bone mass measurements should be used in screening, their clinical utility in specific circumstances is becoming established.