Rheumatoid arthritis (RA) is a systemic, chronic inflammatory disease in which chronic polyarthritis involves diarthrodial joints symmetrically and bilaterally. Synovial lining cells undergo hyperplasia. The result is a synovial lining thrown into numerous villi and frond-like folds that fill the peripheral recesses of the joint. As the synovium undergoes hyperplasia and hypertrophy, it creeps over the surface of the articular cartilage and adjacent structures. This inflammatory synovium is termed a pannus (cloak). The pannus covers the articular cartilage and isolates it from the synovial fluid. Synovial calcification (choice A) does not occur in RA. Pannus may destroy cartilage (choice C) by depriving it of nourishment.Diagnosis: Rheumatoid arthritis