The established standard bone density test is dual-energy X-ray absorptiometry, or DEXA.
Measurements are most commonly taken of your lower spine and both hips. Occasionally, the test may include the bones in the forearm.
The exam is performed with you comfortably lying down on your back. During the spinal portion of the examination, your legs are raised and resting on a soft foam cushion, which straightens your spine.
When examining your hips, your feet are placed in a brace to rotate your hips inward. The scanner slowly passes above the areas of interest as it collects information that is used to make a diagnosis.
The exam usually lasts for about 30 to15 minutes.