Shoulder arthritis. Distinguishing among the many causes of inflammation.

Shoulder inflammation occurs in many rheumatic diseases. It is present in about half of the patients with rheumatoid arthritis but in a higher percentage of patients with less common diseases (eg, amyloid arthropathy, polymyalgia rheumatica). Shoulder arthritis, probably more than arthritis involving any other joint, requires prompt diagnosis and treatment to prevent loss of motion and function. For most patients, antiinflammatory medications, range of motion exercises, and instruction in joint protection constitute adequate treatment. A baseline shoulder roentgenogram is usually recommended. Intraarticular corticosteroid therapy may be a helpful adjunct, provided infection has been excluded.