Osteoporosis FRAX Basics

Osteoporosis is a disorder of reduced bone strength that increases fracture risk, often before the patient has symptoms. A T-score helps describe bone density, but density alone does not capture the patient’s entire probability of fracture. Age, previous fragility fracture, glucocorticoid exposure, falls, frailty, and other clinical factors can make a patient more vulnerable than the BMD value suggests. FRAX converts selected risk factors, with or without femoral neck BMD, into two 10-year probabilities: major osteoporotic fracture (MOF) and hip fracture. MOF includes clinical spine, hip, forearm, and proximal humerus fractures. The result supports a treatment discussion; it is not a diagnosis and is not a substitute for clinical judgment. The Canadian decision is especially vulnerable to two errors. One is importing a risk calculator from another country, whose calibration is not interchangeable with the Canadian model. The other is treating the percentage as decisive when the patient has a recent fracture, repeated falls, frailty, or a fracture pattern that FRAX underrepresents. A reassuring number does not make a recent vertebral fracture safe to defer.