What is a bone density test or DEXA?
This simple and non-invasive imaging test uses very low dose Xray to measure bone thickness and strength. Medical experts consider DEXA scans to be the “gold standard” when it comes to diagnosing osteoporosis, tracking changes in your bones as you age, and determining what bone health medications you may need. The test is quick, easy, painless, and inexpensive.
What is osteoporosis?
Osteoporosis is a term used to describe brittle bones. As you age, your bones can lose thickness and strength. Over time, bones can get weaker and can break more easily. This is most common in postmenopausal women. Osteoporosis is considered a “silent” disease because it doesn’t hurt. Many people don’t realize they have osteoporosis until after they break a bone from a minor fall.
What is Osteopenia?
Osteopenia is a term used to describe “low bone mass.” Many individuals, including those who are slender and very active, have lower bone mass. But this does not necessarily mean that they will develop osteoporosis. Osteopenia is not “pre-osteoporosis,” but sometimes, if a person has other risk factors for fracture, an osteoporosis medication will be recommended to help prevent future fractures.
How does a DEXA scan work?
DEXA scans measure the mineral content in certain bones, such as the hip, spine and/or wrist.
- You will be asked to lie on a special DEXA x-ray table. The technologist will help position your correctly and use positioning devices such as foam blocks to help hold the desired position.
2. As the arm of the DEXA machine passes over the body, it uses two different x-ray beams. The beams use very little radiation.
3. The scanner translates the bone density measurement data into pictures and scores.
4. Your healthcare provider is sent a copy of the report and scores to discuss with you. This report can also be provided directly to you.
The entire scan is less than 15 minutes.
Who should get a DEXA scan?
Research shows women start losing bone mass earlier and faster than men. So, it’s usually recommended women get a DEXA scan to screen for osteoporosis at younger ages compared to men.
Consider a DEXA scan if you have one or more risk factors for osteoporosis or fractures:
- Bone density tests are recommended for all women aged 65 and older; and for younger women at higher-than-normal risk for a fracture. Men should consider screening if they’re over 70 or at high risk for thinning bones.
- Family history: If one or more family members have had osteoporosis or more than one fracture, you could be at a higher risk for bone loss.
- Previous fracture injuries: Breaking a bone, especially after age 50, may be a sign that you’re at greater risk. Porous (less dense) bones break more easily.
- Medications: Some medications, such as the steroid prednisone, cancer drugs, and drugs used after an organ transplant can weaken your bones.
- Your overall health: Many chronic medical disorders can make your bones more likely to break. Risky conditions include rheumatoid arthritis, lupus, diabetes, liver disease and kidney disease.
How often should a DEXA scan be done?
Medicare allows a DEXA scan to be done once every two years, and this is the current recommended timeframe. There are exceptions to this rule if you have certain diseases.
How should I prepare for a DEXA scan?
Before your test, please do the following:
- Stop taking calcium supplements 24 hours before your test: This includes multivitamins as well as antacids such as TUMS® (commonly used to treat heartburn).
- Wear loose-fitting clothing with no metal: Wear comfortable clothes. Try to choose items that don’t have metal (zippers, buttons or buckles). Sweatpants and a casual top may be good choices.
- You will be asked to fill out a questionnaire that asks about your current health, your family history of broken bones, smoking history, and current medications
What should I expect after a DEXA scan?
DEXA scans are quick and painless. You should be able to resume your usual activities immediately after the test.
Your healthcare provider will explain your test results and help you understand what they mean for your health.