Osteoporosis is a silent disease which can significantly increase an individual's risk of fracture. Fractures can be physically debilitating and consequently cause a financial burden on the patient, so it is key to treat osteoporosis before a fracture occurs. Osteoporosis is defined based on the patient's bone mineral density (BMD) as compared to a young adult's BMD using standard deviations (SD). Normal BMD is within 1 SD of young adult mean, osteopenia is between 1 and 2.5 SD less, and osteoporosis is greater than 2.5 SD less than the mean. Severe osteoporosis is defined similar to osteoporosis but includes the presence of fragility fractures.