Bone Densitometry (DEXA)

What is Bone Densitometry?
Bone densitometry is a widely used technique for measuring bone mineral density and diagnosing the presence of osteoporosis. To detect osteoporosis, doctors use a form of x-ray technology called dual- energy x-ray absorptiometry (DEXA). DEXA is a quick and painless procedure for measuring bone loss. Measurement of the spine and hip are most commonly done.

When is Bone Densitometry used?
Bone densitometry is commonly used to diagnose osteoporosis, a condition that often affects women after menopause, but also can be found in men. Osteoporosis is a gradual loss of calcium that causes the bones to become thinner, more fragile and more likely to break. Bone densitometry can assess your risk for developing fractures. If your bone density is low, your physician can work with you on developing a treatment plan to help prevent fractures. Bone densitometry can also track the effects of treatment for osteoporosis.

Some of the reasons your doctor may recommend a bone density test include:

  • You are post-menopausal and not taking estrogen
  • You have a history of hip fracture or smoking
  • You are a post-menopausal female with a small, thin frame
  • You are a male with clinical conditions associated with bone loss
  • You use medications known to cause bone loss, including steroids, anti-seizure medications or high-dose thyroid replacement drugs.
  • You have type 1 diabetes, liver disease, kidney disease or a family history of osteoporosis
  • You have a thyroid condition, such as hyperthyroidism
  • You received a fracture from only minimal trauma
  • You have had a recent x-ray that shows a vertebral fracture or signs of osteoporosis.

How do I prepare for the procedure?
Wear loose, comfortable clothing. Try to avoid clothes that have zippers, belts or buttons made of metal. Inform your physician if you have recently had a test that required you to drink barium or be injected with contrast material (such as a CT scan or nuclear medicine test); you may have to wait several days after these tests to have a bone density test. There are no restrictions on what you can eat before the exam.

What does the DEXA equipment look like?
Our DEXA device has a large flat table with an arm suspended overhead.

What should I expect during my exam?
The exam will last approximately 15-30 minutes. Depending on what you wear to the exam, you may be asked to change into a gown or scrub pants. If your clothes do not have any metal on them, you won’t need to change. You will lie on your back on a padded table.

We will examine your spine and left hip. During the examination of you spine, your legs will be supported on a padded box in order to flatten your pelvis and lower spine. Sometimes we look at the spine from the side. For that picture, you will be asked to lie on your left side. During the exam of the hip, your feet will be placed in a brace that helps to rotate the legs inward. Once you are in position, a detector moves slowly over the area to be imaged and sends information to a computer.

While the exam is in progress, you will be asked to hold as still as possible to ensure a clear and useful image. The procedure is painless. The amount of x-ray used is very small – equivalent to about 1/10 the dose received from a chest x-ray.

How do I get the results of my exam?
After your exam is completed, the results of your bone density exam are interpreted by a radiologist - a physician specially trained to diagnose conditions by interpreting medical images. A detailed report of your results is sent through the mail to your doctor. It may take a few days to reach your doctor. When he/she receives the results, they will discuss them with you and develop a treatment plan for you if necessary.

What are the limitations of Bone Densitometry?
DEXA Bone Densitometry is of limited use in people with spinal deformity or those who have had previous spinal surgery. It is also limited in patients who have had bilateral hip replacements. Osteoarthritis and verterbral compression fractures may also interfere with the accuracy of the test.

Our Bone Densitometry table has a weight limit of 300 pounds. There are other options if you weigh more that 300. Call for more information.