Introduction
People can have osteoporosis without any signs or symptoms. When you have osteoporosis, your bones become weak and are more likely to break. Because it is a disease that can be prevented and treated, an early diagnosis can make a difference. At any age, it is never too late to take steps to protect your bones and prevent fractures (broken bones).
You can find out whether you have osteoporosis or if you should be concerned about your bones by getting a bone mineral density (BMD) test. A BMD test uses a special machine to measure bone density. Some people also call it a bone mass measurement test. This test lets you know the amount of bone mineral you have in a certain area of bone. Bone density testing can be done on different bones of your body, including your hip, spine, forearm (between the wrist and elbow), wrist, finger or heel. A BMD test is safe and painless, and it provides important information about your bone health. Your healthcare provider uses this information to make recommendations to help you protect your bones.
If you are diagnosed with osteoporosis, your healthcare provider may order laboratory
and other tests. These tests can help your healthcare provider find out if you have another medical condition causing bone loss.
What A BMD Test Can Do
A BMD test is the only way to detect low bone density and diagnose osteoporosis. The lower a person’s bone mineral density, the greater the risk of having a fracture. A BMD test is used to:
• Detect low bone density before a person breaks a bone
• Predict a person’s chances of breaking a bone in the future
• Confirm a diagnosis of osteoporosis when a person has already broken a bone
• Determine whether a person’s bone density is increasing, decreasing or remaining stable (the same)
• Monitor a person’s response to treatment
Who Should Have a BMD Test?
There are some reasons (called risk factors) that increase your likelihood of developing osteoporosis. The more risk factors you have, the more likely you are to get osteoporosis and broken bones. Some examples are being small and thin, older age, being female, a diet low in calcium, lack of enough vitamin D, smoking and drinking too much alcohol.
Your healthcare provider may recommend a BMD test if you are:
• A postmenopausal woman under age 65 with one or more risk factors for osteoporosis
• A man age 50-70 with one or more risk factors for osteoporosis
• A woman age 65 or older, even without any risk factors
• A man age 70 or older, even without any risk factors
• A woman or man after age 50 who has broken a bone
• A woman going through menopause with certain risk factors
• A postmenopausal woman who has stopped taking estrogen therapy (ET) or hormone therapy (HT)
Some other reasons your healthcare provider may recommend a BMD test:
• Long-term use of certain medications including steroids (for example, prednisone and cortisone), some anti-seizure medications
and aromatase inhibitors
• A man receiving certain treatments for prostate cancer
• A woman receiving certain treatments for breast cancer
• Overactive thyroid gland (hyperthyroidism) or taking high doses of thyroid hormone medication
• Overactive parathyroid gland (hyperparathyroidism)
• X-ray of the spine showing a fracture or bone loss
• Back pain with a possible fracture
• Significant loss of height
• Loss of sex hormones at an early age, including early menopause
• Having a disease or condition that can cause bone loss (such as rheumatoid arthritis or anorexia nervosa
What your T-score means:
A T-score between +1 and -1 is normal bone density. Examples are 0.8, 0.2 and -0.5.
A T-score between -1 and -2.5 indicates low bone density or osteopenia. Examples are T-scores of -1.2, -1.6 and -2.1.
A T-score of -2.5 or lower is a diagnosis of osteoporosis. Examples are T-scores of -2.8, -3.3 and -3.9.
The lower a person’s T-score, the lower the bone density. A T-score of -1.0 is lower than a T-score of 0.5; a T-score of -2.0 is lower than a T-score of -1.5; and a T-score of -3.5 is lower than a T-score of -3.0.
Considerations
Regular BMD testing can be important in combating osteoporosis in certain people. The overall cost-benefit value of screening everyone, including those who are not at high risk, is still a matter of debate. Many insurance companies today will pay for bone density testing under certain circumstances.
Most experts agree postmenopausal women over age 65 years are at highest risk and should have bone density tests.
Woman under 65 may also be screened if they have additional risk factors, such as:
Chronic rheumatoid arthritis
Fracture (if they are over 50)
Early menopause (either from natural causes or surgery)
Smoking
Strong family history of osteoporosis
Taking corticosteroid medications (prednisone, methylprednisolone) every day for more than 3 months
Three or more drinks of alcohol per day on most days
Simple bone density scans using portable machines may be available as part of health fairs or screenings. These portable scanners may check the density of your wrist or heel. However, keep in mind that hip and spine scans are more reliable.
Alternative Names
BMD test; Bone density test; Bone densitometry
