A doctor can see osteoporosis on a dual X-ray scan, but not always on a traditional radiograph.

In some cases, a doctor may suspect a loss in bone mineral density by examining conventional X-rays of the spine or hip, but these radiographs don’t usually predict, detect, or confirm early osteoporosis with precision.

In general, a loss of more than 30% bone mineral density is necessary for an X-ray to reveal osteoporosis.

Conventional X-ray radiography is useful for detecting fractures, dental cavities, pneumonia, digestive blockages, some tumors, and foreign objects, among similar uses.

If a doctor or radiologist examines your X-rays and believes you may have a loss or change in bone mineral density, they may suggest you have a dual X-ray absorptiometry (DEXA or DXA) scan. This is the gold standard for screening osteoporosis.

DEXA is a noninvasive and quick test that uses low dose X-rays to measure bone mineral density, mainly in the spine or hip bones.

Absorptiometry means the test measures how much radiation a tissue absorbs to find out how dense it is.

Healthcare professionals use DEXA to diagnose osteoporosis and monitor progress once treatment starts. It can also predict the risk of fractures and detect osteopenia, which is when bone mineral loss is observed but not enough to qualify as an osteoporosis diagnosis.

For a DEXA scan, you lie on an exam table while a computerized scanner device moves slowly over you. A healthcare professional may instruct you to rest your legs over a bolster pillow under the knees and to not move while the scanner passes over you.

The whole process may take about 7 minutes and no preparation is necessary on your part.

Most DEXA scans will examine your hip and spine bones. But peripheral DEXA of the wrists and heels is also available, although considered not as accurate as hip and spine scans to predict the risk of fractures.

A doctor may refer you to a DEXA test if they see or suspect changes in bone density in an X-ray or another imaging test, or if you have one or more osteoporosis risk factors.

  • females over the age of 65 years
  • males over the age of 70 years
  • females or males who’ve had a bone fracture after the age of 50 years
  • females and males over age 50 years who:

A doctor will compare the results of a DEXA scan with the average or expected bone density of a younger person without osteoporosis and a person of your age, sex, and race. If they find your bone density is lower than expected, they may diagnose osteopenia or osteoporosis.

DEXA test results are provided as T-scores, which indicate standard deviations from the average. Here’s what DEXA results for a hip scan may mean:

  • T -1 or above: Normal
  • Between T -1 and T -2.5: Osteopenia
  • T -2.5 or lower: Osteoporosis
  • T -2.5 or lower with the presence of a small fracture: Severe osteoporosis

Although a DEXA scan is the most accurate method of predicting and diagnosing osteoporosis, other specialized tests may also help detect or predict the condition or assess the risk of bone fractures. These may include:

  • quantitative computed tomography (QCT)
  • biomechanical computed tomography (BCT)
  • radiofrequency echographic multi spectrometry (REMS)
  • pulse-echo ultrasound (P-EU)

However, DEXA is usually the preferred screening test for bone mineral density loss.

If you have a history of osteoporosis in your family, have had several fractures (especially after age 50 years), have vitamin D deficiency, or have gone through early menopause, consider asking your healthcare professional about an osteoporosis screening. Most insurance companies will cover some of the cost of a bone density test.