What is Bone Mineral Densitometry?

Bone mineral densitometry (BMD) determines the amount of bone and over time can track loss (and the risk of developing osteoporosis) by measuring radiation absorption by the skeleton. Various bones are used, but the best indication comes from those in the hip and spine.

What conditions is it designed to treat?

BMD is used to identify and monitor changes in bone mass. Calcium, which increases bone mass, is constantly added to and taken from bone. In other words, bone growth is a dynamic and constantly changing process. If calcium is not replaced at the same rate that it is lost, bones become porous. Eventually, osteoporosis develops and bones become brittle and break easily.

How is the procedure done?

There are several methods used to measure bone density: (1) Single-photon Absorptiometry (SPA)– an x-ray of the forearm and heel, (2) Dual-photon Absorptiometry (DPA) and (3) Dual-energy X-ray Absorptiometry (DXA)—both x-ray spine and hip, (4) Quantitative Computed Tomography (QCT)—an x-ray of spine and forearm, (5) Radiographic Absorptiometry—an x-ray of the hand, (6) Peripheral Dual-energy X-ray Absorptiometry (PDA)—an x-ray of the wrist, and (7) Ultrasound—sonar waves pass through air or water measuring density in outlying areas of the body, such as the heel.

What are the potential risks?

There are essentially no known risks. One potential risk includes exposure to harmful radiation due to x-rays. This amount is very low. There is no pain associated with the procedure.

What are special instructions after the procedure?

Since the procedure is non-invasive, patients can return to normal activities immediately.

Remember: Women can help prevent osteoporosis by taking calcium supplements, performing weight-bearing activities such as weight-lifting and walking, using hormone replacement therapy (HRT) to increase estrogen levels, limiting alcohol intake, and not smoking.

Thomas G. Stovall, M.D.

Dr. Stovall is a Clinical Professor of Obstetrics and Gynecology at the University of Tennessee Health Science Center in Memphis, Tennessee and Partner of Women’s Health Specialists, Inc.