Dual energy X-ray absorptiometry (DEXA) is a test that measures the density of your bones.
The DEXA scan is an x-ray scan that uses a small amount of radiation to take pictures of different bones. These pictures are used to measure the density of the bones at the spine, hip, and forearm. It can also take pictures of other bones such as a finger or the heel bone. Measurements of the spine and hip are called central DXA. Those done on the arms or legs are called peripheral DXA. In some cases, your doctor may order a whole body scan.
This test will help your doctor assess the density of your bones. It will help determine if you have osteoporosis, a bone-thinning disease. This information may be used to predict your risk of bone fractures.
An x-ray uses radiation to make images. The low levels of radiation from a single x-ray will not affect most people. If you are pregnant or think you may be pregnant, talk to your doctor before the x-ray. Radiation may be harmful to developing babies.
Central DXA measures bone density in the hip and spine. You will be asked to lie on a table. Your position will depend on the area being examined. You will be asked to hold still and may be asked to hold your breath while the X-ray is taken. The X-ray will be taken and sent to a computer monitor.
The test results are usually available within a few days. Your test results will show 2 types of scores:
These test results will help your doctor determine your risk for bone fractures.
National Osteoporosis Foundation
Ortho Info—American Academy of Orthopaedic Surgeons
American College of Radiology. Guideline for the Performance of Dual Energy X-ray Absorptiometry. Available at: http://www.acr.org/~/media/eb34da2f786d4f8e96a70b75ee035992.pdf. Updated 2014. Accessed February 18, 2016.
Bone density scan. RadiologyInfo.org—Radiological Society of North America website. Available at: http://www.radiologyinfo.org/en/info.cfm?pg=dexa&bhcp=1. Updated February 12, 2015. Accessed February 18, 2016.
National Osteoporosis Foundation. Clinician's Guide to Prevention and Treatment of Osteoporosis. Washington, DC: National Osteoporosis Foundation, 2010. Available at: http://www.nof.org/files/nof/public/content/file/344/upload/159.pdf. Accessed February 18, 2016.
Osteoporosis: bone density tests. Am Acad Orthop Surg Bull. 1999;47(3).
Osteoporosis. EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed. Updated December 13, 2015. Accessed February 18, 2016.
Sartoris D, Dalinka MK, Alazraki N. Osteoporosis and bone mass measurement. Radiology. 2000;215(suppl):397-414.
Last reviewed March 2017 by EBSCO Medical Review Board Michael Woods, MD, FAAP
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.