Bone Mineral Density Test

What is a bone mineral density test?

A bone mineral density test (also known as a Dexa scan or a Bone Density Scan) measures the thickness, or density, of the spine, hip and/or forearm, which are common sites for fractures due to osteoporosis. Bone mineral density is measured with a painless, noninvasive test using a series of x-rays.

A bone mineral density test has very little radiation exposure, takes a short period of time and is highly accurate and inexpensive. Because of the accuracy of this test, repeated measurements are often taken during a bone mineral density test. Repeated measurements are taken to track bone loss over time, or to evaluate the effectiveness of a treatment.

During a bone mineral density test, you will lay on your back on a table while a scanner arm moves back and forth over the part of your body being studied. Typically, a bone mineral density tests takes approximately 10 to 15 minutes to complete.


  • You may continue with your usual diet and medications before and after the test.
  • Please wear comfortable clothing that does not have any metal zippers, buttons, buckles or decoration.
  • Remember to tell the technologist if you had recent fractures or metal implants (hip, knee, etc.).
  • You should not have any other medical tests that use barium at least 72 hours before your bone mineral density test. It is extremely important for you to tell the technologist if you had a test that used barium in the last three days.
  • Remember to bring the written order (prescription), for this test, given to you by your doctor.


  • There are no precautions with a bone mineral density test because the amount of radiation to which you are exposed is so low.