Imaging techniques in rheumatology: conventional radiography in rheumatoid arthritis

Conventional radiography is still regarded the gold standard for imaging techniques in rheumatoid arthritis (RA). It is a very important tool for the diagnosis, the differential diagnosis, and the evaluation of the course and prognosis of the disease. Special advantages of conventional radiography are the worldwide availability and experience with the method over decades and the relatively low costs. Moreover, x-rays can be stored and re-evaluated over long periods of time. Joint damage caused by RA can be quantified by means of scoring methods. The amount of destruction correlates well with functional disability over time. The inhibition of damage progression seen on radiographs is the most important characteristic of a DMARD. Typical radiographic changes are part of the ACR classification criteria of RA. Technically, bone structure can be demonstrated with a high local resolution better than with all other imaging techniques, whereas only indirect conclusions can be drawn concerning soft tissue and cartilage lesions. This review includes recommendations given by the "Commission on Imaging Techniques" of the German Society of Rheumatology regarding technical and personal preconditions, costs, indication as well as practical performance of radiography in RA. In addition, radiographic changes that can be expected in RA including destruction and repair are discussed briefly.