Another look at osteoarthritis.

One hundred consecutive cases of osteoarthritis seen in a medical clinic have been reviewed and contrasted with 100 patients with rheumatoid disease. Osteoarthritis was usually a polyarticular disease and as symmetrical in distribution as rheumatoid; the knees and hands were the most commonly involved sites. Evidence of inflammation was often found in patients with osteoarthritis and included morning stiffness, redness of distal interphalangeal joints, warmth, and effusions in the knees. In many cases there was either radiological or electron microscopical evidence of deposition of calcium salts. These findings do not support the concept of osteoarthritis as a mechanical, noninflammatory 'wear and tear' condition. An active metabolic abnormality of articular cartilage resulting in cartilage destruction, calcification, and inflammation is suggested as being more compatible with the findings.