Imaging of sternocostoclavicular joint in spondyloarthropaties and other rheumatic conditions.

OBJECTIVE To retrospectively evaluate the role of the various imaging techniques in the study of the sternocostoclavicular joint, in patients with spondyloarthropathies and other rheumatic conditions and to assess potential pitfalls in the radiological diagnosis. SUBJECTS AND METHODS Thirty patients, 11 male and 19 female, mean age 45 years, with involvement of the sternocostoclavicular joint as part of rheumatologic disorders (psoriatic arthritis, ankylosing spondylitis, Tietze syndrome, SAPHO syndrome, and condensing osteitis of the clavicle) were studied. Conventional radiography, CT, MRI and bone scintigraphy were performed. The following imaging findings were evaluated: soft tissue swelling, bone sclerosis, cortical bone erosions, joint space narrowing, subchondral sclerosis, periosteal new bone formation, synovial reaction and intrarticular effusion. All the images were independently reviewed by two musculoskeletal radiologists. RESULTS Conventional radiography demonstrated only sclerosis of the clavicula in 8 pts (26%) and the sternum in 3 pts (10%), cortical bone erosions in 7 pts (23%), joint space narrowing in 6 pts (23%) and periosteal bone formation in 2 pts (10%). At the CT examination sclerosis of the clavicula and the sternum was observed in 13 pts (44%), cortical bone erosions in 22 pts (76%), joint space narrowing in 10 pts (34%), ligament ossification in 12 pts (41%), subchondral sclerosis in 9 pts (34%) and periosteal bone formation in 10 pts (34%). The MRI was the most sensitive technique in the evaluation of the soft tissue swelling in 9 pts (56%), intrarticular effusion in 13 pts (81%) and synovial reaction in 13 pts (81%). Finally, bone scintigraphy showed an increased uptake at the sterno-costoclavicular joint in all patients who underwent the examination. CONCLUSION The radiological evaluation of the anterior chest wall in patients with different rheumatic disorders represents a problem of difficult diagnostic evaluation both for the anatomic region complexity and for the variability of the radiographic findings. The integrated use of X-ray, CT, MRI and nuclear medicine is suggested to avoid misdiagnosis.