How does a Bone Density (DEXA) scan work?

A bone density scan, also known as a DEXA scan, BMD test, or DXA scan, is a type of low-dose x-ray scan. This type of scan measures the amount of calcium and minerals within the bones, and can also measure the strength (bone density) and thickness (bone mass) of your bones.

It’s recommended for women over the age of 65 to have a bone density scan, as well as men over the age of 70. If you’ve experienced several bone fractures, have a very low body weight, or have decreased in height more than half an inch in one year it is also recommended to have a DEXA scan done to check for osteopenia or osteoporosis. 

What is it used for?

A bone density scan can be used to:

  • Diagnose ostopenia or osteoporosis: it is common for people’s bones to become thinner as they age. Osteopenia (low bone mass) can eventually lead to the condition Osteoporosis, which causes bones to become very thin and brittle. Individuals with osteoporosis have a high risk of bone fractures.
  • Predict risk of future fractures: as mentioned above, thin and brittle bones can lead to an increased risk of painful bone fractures. A bone density scan can determine how susceptible a patient may be to fractures in the future. This can be helpful for creating safety guidelines for patients at home and in their daily lives to lower the chances of experiencing a fracture.
  • Determine whether osteoporosis treatments are working: most treatments for osteoporosis and osteopenia are targeted at remineralizing the bones or preventing further demineralization. DEXA scans can be used to check the progress of these treatments and determine whether changes need to be made to a treatment plan to improve their effectiveness.