You are here:

Ask the doctor: Which bone density test should I have?

Q. My doctor has recommended a bone density screening, but the medical center with the full-body scanner is a 45-minute drive from my house. A health fair at a neighborhood church offers a bone density test using a foot scanner. Would that be as accurate?

A. The foot scan is called a quantitative ultrasound, and it usually measures the bone density of the heel bone.
It appears to be at least as good as clinical risk factors—such as older age, family history of bone fractures, low body mass index, smoking, corticosteroid use, and excessive alcohol consumption—for identifying people at high risk for osteoporosis.

However, there are limitations to ultrasound. It doesn’t reliably exclude or confirm osteoporosis that would be found using a DEXA scanner, and there are no established criteria for diagnosing osteoporosis and recommending treatment based on ultrasound. If ultrasound finds that you’re at high risk for a fracture, you’ll need a DEXA scan to determine whether you need treatment.

So although ultrasound might be able to predict whether you might have a fracture in the future, the full-body DEXA scan is recommended for screening and for making decisions about treating osteoporosis. If you can find the time to get to the medical center for a DEXA scan, I’d advise you to do that. If not, an ultrasound might be an acceptable alternative.

— Anne Fabiny, MD
Editor in Chief, Harvard Women’s Health Watch

Posted by: Dr.Health

Back to Top