Heterogeneity of age-related fractures: implications for epidemiology.

Despite a general impression to the contrary, the risk factors for age-related fractures are poorly understood. There are indications, however, that these risk factors may vary from one skeletal site to another, depending on the pathophysiology of bone loss at the site and on the relative contributions of trauma and bone strength. Accurate knowledge of risk factors for specific fractures could help in the design of efficient screening and treatment programs for osteoporosis, while a clear understanding of fracture heterogeneity might lead to new hypotheses concerning etiology. However, a much more comprehensive approach to the study of the risk factors for age-related fractures will be necessary to achieve these ends.