What happens during the test?
The bone mineral density test is non-invasive (nothing is inserted through the skin or into a body cavity) and pain-free. Areas tested may include the lower part of your spine (also called the lumbar region), the upper part of the thigh bone near the hip joint, the wrist, the forearm, the finger, or the heel.
For most bone mineral density tests, you lie on a table while an X-ray detector moves above your spine and hip. You may have one or both sides of your body scanned. The detector measures the amount of radiation, in the form of X-rays, which are able to pass through your bone. The denser (stronger) your bones are, the less radiation will be able to pass through.
How should I prepare for this test?
BMD tests require very little preparation. You only need to avoid wearing jewellery and metal objects or buttons. You may need to wear a hospital gown. Tell your doctor or the person doing the test if you have had a bone fracture in the area being scanned (this can artificially increase your score, making your bones appear thicker than they are) or a test involving barium or dye injections in the last 2 weeks (this can interfere with the test).
Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications that you are taking. Also tell them about any medication allergies and medical conditions that you may have. Ask your doctor or pharmacist whether you need to stop taking any of your medications before the test.
What can I expect after the test?
You can return to your normal activities immediately after the test.
Results
By comparing your results with those of other people, your doctor determines your T-score. The T-score is a calculation that lets you know how dense your bones are compared to the average for young healthy adults of your gender who are at their highest lifetime bone mass.
If you have a high amount of bone loss, your doctor will tell you, in standard deviation units (SDs), how much below "normal" you are. If your bone density is more than 2.5 SDs below normal, you will be diagnosed with osteoporosis.