To analyse the validity of Cyriax's concept of the "capsular pattern" in the diagnosis of osteoarthritis (OA) of hip and knee, data on 200 patients were analysed. The capsular pattern with limitations of medial rotation, flexion, and abduction, was not present as a distinct pattern in patients with OA of the hip. In patients with OA of the knee, an indication of the existence of a capsular pattern of the knee, with limited ranges of motion for both flexion and extension was found in subgroups of patients. It is concluded that the capsular pattern cannot be regarded as a valid test for the diagnosis of OA of the hip or knee. Further investigations in subgroups of patients are recommended.