Why is a DEXA scanner used in a bone density scan?

DEXA uses low-dose X-rays to compare how much radiation passes through bone and soft tissue. The measurement commonly focuses on areas where bone loss can be clinically important, such as the hip and lower spine. A clinician interprets the result alongside your age, medical history, medicines, previous fractures, and other factors.

The result is not a prediction that a fracture will happen. It is one piece of information that can help decide whether lifestyle measures, investigation for an underlying cause, monitoring, or treatment should be considered.

Follow the imaging centre’s instructions before you attend. Tell the staff if you are pregnant or think you might be pregnant, have recently had imaging involving contrast, or cannot lie flat comfortably. Wear clothing without metal around the area being scanned if possible, and remove jewellery or other metal items when asked.

During the scan you lie still on a padded table while the machine passes over the relevant area. The appointment team can explain the position and when you can resume normal activities.

Arrange a medical review after a fracture from a minor fall or impact, noticeable loss of height, new persistent back pain, or if you have been advised to assess bone health because of a health condition or medicine. Seek urgent care after a fall if there is severe pain, a visible deformity, inability to bear weight, or numbness or weakness.

Ask which body areas will be measured, how your result will be explained, and whether repeat scanning is useful for your situation. You can also ask whether your diet, exercise, falls risk, medicines, or other health conditions need review.