The recent evolution of ultrasound in juvenile idiopathic arthritis.

Juvenile idiopathic arthritis (JIA) is the most common chronic joint disease in paediatric rheumatology. Over the last two decades, ultrasound (US) has emerged as a tool with the potential to enhance disease assessment and management of JIA. This imaging modality is safe and well tolerated by children and can be easily applied bedside in the clinical setting. Owing to the lack of published studies regarding the validity and reproducibility of US in JIA and the difficulties in interpreting images of children, US was initially perceived like an art rather than a science. In recent years, a great deal of efforts has been made in order to fill the gap of scientific knowledge on US between paediatric and adult rheumatology. This has yielded significant breakthroughs, such as the achievement of valuable information about the anatomical peculiarities of the growing skeleton on US, including internationally agreed definitions on B-mode and Doppler US of components for the normal joints, and the development of a standardised scanning protocol for US examination suitable for use in children. The precise role of US in JIA, however, is yet to be fully defined. Although further research regarding the use of US in joint inflammatory pathology in paediatrics is required, this imaging modality may well possess the necessary properties to pursue the best practice in the care of children with JIA in the near future. The present review provides information on the recent advances that have made the application of US increasingly promising for the management of JIA.