- Concurrent articular disease interfering with the evaluation of OA and/or pain such as articular dysplasia, aseptic osteonecrosis, acromegaly, Paget's disease, hemophilia, hemochromatosis, chondromatosis, villonodular synovitis of the knee, seronegative spondyloarthropathy, rheumatoid arthritis, gouty arthritis , infectious arthritis, radiculalgia in the lower limbs, arteritis, etc.