Ultrasound in rheumatoid arthritis

Ultrasound in increasingly used in rheumatology practice in the assessment of inflammatory patient, including facilitating early diagnosis of rheumatoid arthritis (RA), predicting its outcome, measuring structural damage, and monitoring its progression. This imaging modality can visualize both inflammatory and structural changes in patients with unclassified arthritis and RA, as well as other inflammatory arthritides such as psoriatic arthritis (PsA), spondyloarthropathy (SpA), and crystal arthritis. This chapter aims to provide an overview of the recent advances of this technique for in the assessment of RA. Firstly, the principles which underpin the physics of ultrasound are summarized, followed by the musculoskeletal pathologies which are amenable to ultrasound examination. In addition, it also highlights the role of ultrasound in procedures (e.g. ultrasound-guided biopsy and ultrasound-guided injection).