Bone Density


Bone densitometry machine

What is Bone Densitometry (DEXA)?

Bone densitometry, also called dual-energy x-ray absorptiometry, DEXA or DXA, uses a very small dose of ionizing radiation to produce pictures of the inside of the body (usually the lower (or lumbar) spine and hips) to measure bone loss. It is commonly used to diagnose osteoporosis, to assess an individual’s risk for developing osteoporotic fractures. DXA is simple, quick and noninvasive. It is also the most commonly used and the most standard method for diagnosing osteoporosis.

How to prepare for a Bone Density exam?

This exam requires little to no special preparation. Tell your doctor and the technologist if there is a possibility you are pregnant or if you recently had a barium exam or received an injection of contrast material for a CT or radioisotope scan. Leave jewelry at home and wear loose, comfortable clothing. You may be asked to wear a gown. You should not take calcium supplements for at least 24 hours before your exam.

What to expect during a Bone Density exam?

In the examination, which measures bone density of the hip and spine, the patient lies on a padded table. An x-ray generator is located below the patient and an imaging device, or detector, is positioned above.

To assess the spine, the patient’s legs are supported on a padded box to flatten the pelvis and lower (lumbar) spine. To assess the hip, the patient’s foot is placed in a brace that rotates the hip inward. In both cases, the detector is slowly passed over the area, generating images on a computer monitor.

You must hold very still and may need to hold your breath for a few seconds while the technologist takes the x-ray. This helps reduce the possibility of a blurred image. The technologist will walk behind a wall or into the next room to activate the x-ray machine.

How long does a Bone Density exam take?

Bone density tests are a quick and painless procedure. The DXA bone density test is usually completed within 10 to 30 minutes.

When should I know the results of my Bone Density exam?

After your DEXA scan, a radiologist will analyze the images. The radiologist will send a signed report to your ordering healthcare provider within 24 hours of the scan.  Your provider will share the results with you.