The study goal was to use population-based data to model aspects of lifetime osteoporosis impact not previously studied, specifically: (1) to estimate person-years of fracture-related functional impairment against the trajectory of functional status in the general population; (2) jointly to consider hip, vertebral, and Colles' fractures in estimating the percent of women who will ever fracture; and (3) to estimate the lifetime number of fractures expected in a cohort of 10,000 50-year-old white postmenopausal women. The model estimates that 54% of 50-year-old women will sustain osteoporosis-related fractures during their remaining lifetimes. Beyond the functional impairment expected in similarly aged, unfractured women, osteoporosis-related fractures are estimated to cause 6.7% of women to become dependent in basic activities of daily living; 7.8% are expected to require nursing home care for an average of 7.6 years.