ABSTRACT
Osteoporosis is operationally defined on the basis of bone mineral density (BMD) assessment, with recent refinements of the description focusing on measurements at the femoral neck as a reference standard. The principal difficulty for fracture risk assessment is that this threshold has high specificity but low sensitivity, so the majority of fragility fractures occur in individuals with BMD values of the osteoporosis threshold. Risk factors for osteoporotic fractures and for hip fracture were identified from unique population-based cohorts in diverse geographic territories using the primary individual data. The incorporation of fracture risk assessment into clinical practice demands a consideration of fracture probability at which to intervene, both for BMD testing and treatment. Intervention thresholds using age-specific fracture probabilities have been incorporated in a significant number of guidelines, including European guidance for postmenopausal osteoporosis and for glucocorticoid-induced osteoporosis. The hybrid model provides an enhancement of patient assessment by the integration of clinical risk factors alone or in combination with BMD.
