The sternocostoclavicular joint: normal and abnormal features.

Many physicians are unfamiliar with the characteristics of the sternocostoclavicular joint (SCCJ). Disorders of the SCCJ, although common, frequently escape recognition. Computed tomography (CT) with thin slices and no gap is at presentthe best means of investigating the SCCJ. CTfeatures in normal subjects have been described in detail; some are misleading. The most common SCCJ disorder is degenerative disease manifesting as osteoarthritis or as periarticular lesions causing antero-medial dislocation of the clavicle. Septic arthritis is the most severe disorder and can lead to mediastinitis. All inflammatory joint diseases, including spondyloarthropathies, can affect the SCCJ. SCCJ involvement is a typical component of the osteoarticular manifestations seen in patients with palmoplantar pustulosis.