Dual-Energy X-Ray Absorptiometry (DXA) Test: About This Test

What is it?

Dual-energy X-ray absorptiometry (DXA) is a test that uses two different X-ray beams to check bone thickness (density) in your spine and hip. This information is used to estimate the strength of your bones.

Why is this test done?

Bone density testing is often done for:

• People who are at risk for osteoporosis, including:
  • Women who are age 65 and older.
  • Older men.
  • People who take some medications, such as steroids.
  • People who have certain medical conditions, such as hyperparathyroidism.
• People who have osteoporosis, to see how well treatment is working.

How is the test done?

• You will lie on your back on a padded table. You probably can leave your clothes on, but you will remove any metal buttons or buckles for the test.
• You may need to lie with your legs straight or with your lower legs resting on a platform built into the table.
• The machine will scan your bones and measure the amount of radiation they absorb. During this test you are exposed to a very low dose of radiation.

How long does the test take?

The DXA scan, which scans the hip and lower spine, takes about 20 minutes. Other kinds of bone density scans may take 30 to 45 minutes.

What happens after the test?

• You will probably be able to go home right away.
• You can go back to your usual activities right away.

Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor if you are having problems. It's also a good idea to keep a list of the medicines you take. Ask your doctor when you can expect to have your test results.