Atraumatic disorders of the sternoclavicular joint.

The sternoclavicular joint is the diarthrodial articulation between the axial and appendicular skeletons. It is subject to the same disease processes that occur in joints, including degenerative arthritis, rheumatoid arthritis, infection, and subluxation. Most of these conditions present with swelling of the joint, which may be associated with pain and/or tenderness. Plain radiographs can demonstrate changes on both sides of the joint. Because of variations in anatomy, computed tomography scans and magnetic resonance images are often necessary to clarify the pathology. With the exception of acute infection, most conditions can be managed nonsurgically, with joint resection reserved for patients with persistent symptoms.