The central joints of 19 patients identified as suffering from polymyalgia rheumatica were examined using ultrasonography (US). At US 13 patients (68%) were found to have an effusion in the hip and/or glenohumeral joints. Synovial fluid analyses were conducted on the central joints of four patients. These findings suggest that at least one patient group with the syndrome of PMR could better be designated as having axial arthritis and this synovitis might play an important role in the understanding of their symptoms.