What is a DXA scan?
The bone densitometry (DXA) scan assesses quantity of bone. The test can be compared to light shining through curtains on a sunny day. Just as the amount of light that reaches your eye depends on the thickness of the curtains, the amount of light from the DXA scanner that passes through your bones depends on how thick or thin your bones are.
Why does bone density matter?
Low bone density or mass occurs when too much tissue has been lost or not enough has been made. Once this has happened, the bones become weak and as a result, may easily fracture or break.
How does the test work?
During the test you will lie on your back for several minutes. A small x-ray detector will scan your spine and at least one of your hips. You may be asked to lift your legs onto a support to straighten your back.
Who should be tested?
The World Health Organization recommends that males over 50 and females over 40 have a FRAX screening test to determine their 10-year probability of a major fracture. This initial test will indicate if a DXA scan is necessary.
Does the test hurt?
The test does not require injections and will not cause discomfort. You are exposed to the same amount of radiation as a four-hour plane ride.
What comes after the test?
The DXA scan reports the quantity of bone you have. You then should have a through exam and medical history to determine the quality of your bones. Evaluating the quality and quantity determines the strength of your bones which indicates your fracture risk. From there, treatment and monitoring recommendations can be made.