Bone Densitometry (DEXA)
Bone densitometry is also known as dual-energy X-ray absorption, or DEXA for short. It is a painless test to help your healthcare provider diagnose bone disorders.
The results from your DEXA exam can help you understand the strength of your bones. Your results will be compared with the peak bone mass of a similar healthy adult. A bone densitometry exam is more precise than conventional diagnostic imaging (X-rays). It can help to diagnose bone loss at an early stage.
What are DEXA scans used for?
A bone density test is used mainly to diagnose osteopenia and osteoporosis. It is also used to determine your risk of future fracture. The testing procedure typically measures the density of the bones of your spine, lower arm, and hip. Healthcare providers may also order a DEXA scan to:
- Track bone health changes over time.
- Monitor your response to treatment, such as an osteoporosis medication.
- Evaluate body composition, such as how much fat and muscle mass your body has (and where).
Who needs a DEXA scan?
Talk with your healthcare provider about having a bone densitometry test if you have one or more of the following risk factors:
- Your parent, grandparent, or other close relative had osteoporosis or bone fractures.
- You have low body weight, a slight build, or a light complexion.
- You have a history of cigarette smoking or heavy drinking.
- You experienced the onset of menopause before the age of 45.
- Over a long period of time, you have taken medication that accelerates bone loss, such as corticosteroids for treating rheumatoid arthritis or some anti-seizure medications.
- You have already experienced a bone fracture as a result of thinning bones.
- Your ethnicity is either white or Asian.
How does a DEXA scan work?
DEXA scans measure the mineral content in certain bones, such as the hip, spine, and/or wrist. It works this way:
- You will be asked to lie on a special DEXA x-ray table. The technologist will help position you correctly and use positioning devices such as foam blocks to help hold the desired position.
- As the arm of the DEXA machine passes over the body, IT uses two different x-ray beams. The beams use very little radiation to keep the test safer and help to distinguish bone from other tissues.
- The scanner translates the bone density measurement data into pictures and graphs. Bone is most easily seen in white, while the fat and muscle tissue looks like shadows in the technologist’s computer monitor background.
- These results are then reviewed and interpreted by a radiologist or other physician trained in DEXA interpretation.
- Your healthcare provider is sent a copy of the written report to discuss with you and consider what treatment is most appropriate.
Bone Density Test Results
A bone density test determines bone mineral density (BMD). Your BMD is compared to two norms—healthy young adults (your T-score) and age-matched adults (your Z-score). In addition to bone densitometry testing, your healthcare provider may recommend other types of tests, such as blood tests, which may be used to find the presence of kidney disease, evaluate the function of the parathyroid gland, evaluate the effects of cortisone therapy, and/or assess the levels of minerals in the body related to bone strength, such as calcium.
What should I ask my healthcare provider?
Medical experts consider DEXA scans to be the most reliable method for diagnosing osteoporosis and fracture risk. Many individuals lose bone density as they age. But that doesn’t mean you have to accept fragile bones simply as a reality of getting older. It is never too early to learn how to take care of your bones! Ask your provider if a DEXA scan may help assess your bone health today. Then, talk about steps you can take to slow bone loss or protect your bones for years to come.
Bone Density appointments are available at our Lompoc Health - North Third Center.