A bone densitometry scan (DXA or DEXA) is carried out to assess your bone mineral density (BMD)
From this measurement, a diagnosis of osteoporosis (T-score of -2.5 or below) can be made. During a DXA scan, you lie down on the scanner bed (no tunnel); while a low-dose X-ray scanning arm passes over you.
A diagnosis of osteoporosis is only part of the picture; many other factors will contribute to your risk of breaking a bone.
Doctors are now using a fracture risk assessment tool (www.shef.ac.uk/FRAX), to assess your ten year risk of breaking a bone. If you are over 75 years of age you may not need to have a DXA scan.
Most people do not need a repeat DXA scan. However, in certain circumstances a repeat scan may be indicated. This would not usually be carried out until at least 2 years after the previous scan.