Mayo Clinic Health Manager
Get free personalized health guidance for you and your family.
Get StartedDefinition
By Mayo Clinic staffYears ago, the only time osteoporosis — a disease that causes bones to become more fragile and more likely to break — could be detected was after you broke a bone. By then, however, your bones might already be quite weak.
Today a bone density test, also called densitometry or DEXA scan, can determine if you have osteoporosis or are at risk of osteoporosis before you break any bones.
A bone density test uses special X-rays to measure how many grams of calcium and other bone minerals are packed into a segment of bone.
A bone density test is a fairly accurate predictor of your risk. The results from a bone density test can let you know how you compare with other people of your age, sex and other similar characteristics.
Why it's done