Plain radiography plays an important role in the differential diagnosis of arthritis. Rheumatoid arthritis is associated with erosion, osteopenia and soft tissue swelling in a diffuse, bilateral symmetrical distribution in the proximal hands and feet. In contrast, seronegative arthritis shows bony proliferation and often involves the axial skeleton. Radiographic features of osteoarthritis are joint space narrowing, subchondral sclerosis, cysts and osteophytes. Newer techniques of magnetic resonance imaging and ultrasound show great promise for the early detection of arthritis and the demonstration of early response to treatment.
R Hodgson is a senior lecturer at the NIHR Leeds Musculoskeletal Biomedical Imaging Unit, Leeds teaching Hospitals Trust, UK. Competing interests: none declared
PJ O'Connor is a consultant musculoskeletal radiologist at the NIHR Leeds Musculoskeletal Biomedical Imaging Unit, Leeds teaching Hospitals Trust, UK. Competing interests: none declared