Bone Density

The purpose of the Bone Scan

A bone mineral density (BMD) test can help your health care provider confirm a diagnosis of osteoporosis. The test can help in several ways:

• BMD testing is one of the most accurate ways to assess your bone health.
• When repeated over time, it can be used to monitor your rate of bone loss.
• It can detect osteoporosis at its earliest stage, so treatment can begin sooner.
• If you are being treated for osteoporosis, BMD testing can help your health care provider monitor your response to the treatment.

Prep

Remove any jewelry before the BMD test. Inform your health care provider if you may be pregnant.

What to Expect

The scan is painless, although you will need to remain still during the test.

Normal Values

The results of your test are usually reported as a "T score" and "Z score."

• The T score compares your bone density with that of healthy young women.
• The Z score compares your bone density with that of other people of your age, gender, and race.

In either score, a negative number means you have thinner bones than the standard. The more negative the number, the thinner your bones. A T score is within the normal range if it is -1.0 or above.

What Abnormal Results Mean

• A T score from -1 to -2.5 indicates the beginning of bone loss (osteopenia).
• A T score below -2.5 indicates osteoporosis.

   

What the Risks Are

BMD testing involves exposure to a low level of radiation. Most experts feel that the risk is very low compared with the benefits of identifying osteoporosis before you break a bone.