A bone density test — also called densitometry or DXA scan — determines whether you have osteoporosis or are at risk of osteoporosis. Osteoporosis is a disease that causes bones to become more fragile and more likely to break. A bone density test uses X-rays to measure how many grams of calcium and other bone minerals are packed into a segment of bone.
Bone density tests are easy, fast and painless. Virtually no preparation is needed.
Be sure to tell your doctor beforehand if you’ve had recent oral contrast or nuclear medicine tests. These tests require an injection of radioactive tracers that might interfere with your bone density test.
What to expect
Bone density tests are easy, fast, and painless. Virtually no preparation is needed. Bone density tests are usually done on bones that are most likely to break because of osteoporosis. You will not have to change into a gown for this test if you wear loose, comfortable clothing without zippers or metal buttons. You will lie on a padded table and asked to hold very still for approximately five minutes while a mechanical arm passes over your body. The amount of radiation you’re exposed to is very low, much less than the amount emitted during an X-ray. The test usually takes about 10 to 30 minutes. After the exam, you can resume normal activity.