A bone density scan is a test used to measure bone loss, according to the Radiological Society of North America. It is most often used to measure bone loss due to osteoporosis.
Osteoporosis is a condition where calcium is gradually lost from bones, making them more brittle and prone to breaking, according to the Radiological Society of North America. A bone density test uses X-rays to measure the amount of calcium present in a person's bones. It can also be used to monitor the effectiveness of osteoporosis treatment and assess the risk for developing fractures. It is recommended that all post-menopausal women have bone density tests, especially if they are tall or have a family history of osteoporosis.