Bone Densitometry
Bone densitometry, or DEXA (Dual Energy X-ray Absorptiometry), measures the strength of your bones to determine whether you are at risk for developing osteoporosis or osteopenia (decreased bone mass) — osteopenia often develops into osteoporosis. Doctors use the test to develop an appropriate treatment plan to slow the progression of disease and prevent fractures. Early detection can allow doctors to begin therapy when it can be most beneficial.
Osteoporosis is caused by more bone cells being resorbed than being deposited. This imbalance results in a progressive loss of bone density and a thinning of bone tissue. Osteoporotic bones are more porous and therefore more vulnerable to fracture.
What is a DEXA Bone Density Scan?
DEXA stands for dual energy X-ray absorptiometry and is the most widely used test to measure bone mineral density. A DEXA bone density test is more accurate than a regular X-rays or CAT scans and requires less radiation exposure. DEXA scans are now the best method of diagnosing and monitoring osteopenia and osteoporosis.
Using a bone densitometer, physicians can measure patient bone density and follow it over time. If the patient's bone density is low, or decreases at an abnormally fast rate, the patient may be at risk for osteoporosis. Through changes in diet, exercise habits and/or medication, further deterioration of bone can be prevented.
Who Should Get a Bone Density Scan?
Anyone at risk for osteoporosis should get a bone density scan. Postmenopausal women are at highest risk, because estrogen (which falls after menopause) preserves bone strength. But men get osteoporosis, too. Some guidelines include:
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Women older than 65
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Postmenopausal women under age 65. For women under 65, a bone scan is not universally recommended.
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Men age 70 or older
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Women with risk factors for osteoporosis:
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History of bone fracture as an adult
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Current smoking
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History of ever taking oral steroids for more than 3 months
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Body weight under 127 pounds
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Having an immediate family member with a fragility fracture (a broken bone from a minor injury, suggesting osteoporosis).
Contact your doctor about your risk factors for osteoporosis and ask for a referral for a bone density examination. There is no special preparation involved. The exam is very brief and comfortable.