Overview of the radiology of juvenile idiopathic arthritis (JIA).

Plain films remain the basic tool for diagnosis and follow-up evaluation of juvenile idiopathic arthritis (JIA). In this paper, we review the new classification of JIA: systemic arthritis. oligoarthritis (persistent), oligoarthritis (extended), polyarticular arthritis (rheumatoid factor negative), polyarticular arthritis (rheumatoid factor positive), enthesitis-related arthritis, psoriatic arthritis and unclassified arthritis. We will also review regional abnormalities of three stages: an early stage, an intermediate stage, a late stage, as well as the differential diagnosis.