Bone mineral density (BMD) measurement is currently the standard method to diagnose osteoporosis. But it serves not only as a diagnostic tool: the doctor also measures the bone density to control the effect of the therapy, and to predict your individual fracture risk in the future. But there is no method of BMD measurement which could state anything about the bone quality; all techniques focus on the quantity of bone minerals.

To assess bone mineral density, some techniques are available. The most widely used are based on X-ray absorptiometry and dual-energy absorptiometry (DXA) in particular. DXA can be used to assess the bone mineral content of the whole skeleton as well as of specific sites.
DXA measures your bone mineral density and compares it to the average score of a "young normal" healthy adult. Your result, called a "T score," reflects how far off your bone mineral density is from that of an average healthy adult. Scores are measured in negative points, which indicate your risk for breaking a bone.

Other techniques use ultrasound (QUS), or computed tomography (QCT), both applied to the spine or to other parts of the body like the forearm or the heel. So it’s not always necessary that your whole body is examined. But it is important that your doctor always uses the same technique and measures at the same site, because you can’t compare the different methods or the results of the different techniques.

In addition to the measurement of your BMD, your medical history and that of your family are as well as, further risk factors and your lifestyle are important Risk factors. So your doctor will ask you a lot of questions to find out whether you are at risk for osteoporotic fractures.