Epidemiology of fracture risk with advancing age.

Bone loss and structural damage with advancing age lead to skeletal fragility as manifested by low bone mass and deficits in bone geometry, microarchitecture, and material properties. Skeletal fragility, in combination with a greater propensity to fall, results in an increased susceptibility to fractures with aging, known as fragility fractures. Fragility fractures exceed 2 million per year in number and account for nearly 20 billion dollars per year in health care costs in the United States. Advanced age, low bone mass, and previous fracture are strong risk factors for fractures at nearly all skeletal sites, but each type of fracture also has its own set of unique risk factors. Hip fractures are most strongly associated with adverse consequences, but these account for only a minority of fragility fractures. Vertebral fractures comprise the most common manifestation of fragility fracture, but the majority of these fractures are asymptomatic. Most research has focused on the epidemiology of fractures at the hip, vertebrae, and wrist and less is known about other fracture types, which account for 40% of total fragility fractures that are clinically recognized. Future research focused on identification of older adults at high risk of disabling fractures is warranted.