General applications of ultrasound in rheumatology

Ultrasound (US) is a noninvasive imaging technique that continues to gain interest among rheumatologists because of its undoubted utility for the assessment of a wide range of abnormalities in rheumatic diseases. It also has a great potential to be used at the time of consultation as an extension of the clinical examination. Current data demonstrate that the standard clinical approach could result in an insensitive assessment of some the different aspects of the various rheumatic diseases for which US has become a feasible and effective imaging modality that allows early detection of anatomical changes, careful guidance for the aspiration and/or local treatment, and short- and long-term therapy monitoring at the joint, tendon, enthesis, nail, and skin levels. The spectrum of pathological conditions for which US plays a crucial role continues to increase over time and includes rheumatoid arthritis, spondyloarthropathies, osteoarthritis, crystal-related arthropathies, connective tissue disorders, and vasculitis. It is expected that the inclusion of more longitudinal studies with a larger number of patients and more rigorous methodological approach will undoubtedly provide a better understanding of the significance of the abnormal US findings detected in order to provide the proper diagnostic and/or therapeutic approaches. In this article, we analyze the current potential applications of US in rheumatology and discuss the evidence supporting its use in the daily rheumatologic practice.