Use of DXA-based technology for detection and assessment of risk of vertebral fracture in rheumatology practice.

Measurement of bone mineral density (BMD) by dual-energy X-ray absorptiometry (DXA) is the recommended method for diagnosis of osteoporosis and assessment of future fracture risk. However, most patients who will suffer fractures do not have osteoporosis by DXA (T-score of -2.5 or less). Bone strength, which is most closely associated with resistance to fracture, is a composite of both bone density and bone quality, and the latter is not measured by DXA. Thus, other technology is needed for non-invasive and inexpensive assessment of bone strength and fracture risk. Vertebral fractures, the most common clinical fracture in the general population, are of even greater importance in rheumatoid arthritis and other rheumatic disorders. Vertebral fracture assessment (VFA) and trabecular bone scores (TBS), two techniques which can aid prediction of future fracture risk, can be used with currently available DXA machines. Description of these techniques and their potential application to clinical rheumatology practice will be the focus of this paper.