Epidemiology of osteoporosis.

Osteoporosis and related fractures represent a major, and growing, public health concern for the United States and worldwide. The pathogenesis of osteoporosis is complex, requiring attention to the different life phases involved in growth, maintenance, and loss of bone, in addition to non-skeletal factors associated with falls and fractures. While the current clinical definition is based upon bone density measurements, other determinants of skeletal strength, particularly bone quality, are important to identify for future areas of research and prevention efforts. This epidemiologic review describes the definition, pathogenesis, and risk factors, as well as the frequency and impact of osteoporosis, with particular emphasis upon hip fracture.