What does the equipment look like?

There are two types of DXA equipment: a central device and a peripheral device.

Most of the devices used for DXA (also known as Bone Densitometry) are central devices, which are used to measure bone density in the hip and spine. They are usually located in hospitals and medical offices. Central devices have a large, flat table and an “arm” suspended overhead.

Peripheral devices measure bone density in the wrist, heel or finger and are often available in drugstores and on mobile health vans in the community. The pDXA devices are smaller than the central DXA devices, weighing only about 60 pounds. They may have a portable box-like structure with a space for the foot or forearm to be placed for imaging. Other portable technologies such as specially designed ultrasound machines, are also sometimes used for screening. However, central DXA is the standard technique.


How does the procedure work?

The DXA machine sends a thin, invisible beam of low-dose x-rays with two distinct energy peaks through the bones being examined. One peak is absorbed mainly by soft tissue and the other by bone. The soft tissue amount can be subtracted from the total and what remains is a patient’s bone mineral density.

DXA machines feature special software that compute and display the bone density measurements on a computer monitor.


What will I experience during and after the procedure?

Bone density tests are a quick and painless procedure.

Routine evaluations every two years may be needed to see a significant change in bone mineral density, decrease or increase. Few patients, such as patients on high dose steroid medication, may need follow-up at six months.