[Occurrence of pannus in arthrosis]

Eight human femoral heads, surgically removed from patients with the clinical diagnosis: coxarthrosis or necrosis, were examined. In six of these we found severe arthrosis combined with synovitis and pannus formation. The pannus appeared as granulation tissue or fibrous connective tissue covering the surface of the cartilage or growing into it. In most cases the pannus showed a destructive appearance, although newly formed cartilage repair tissue was also observed. There was no indication for a pannus originating from the bone marrow. We therefore assume that we are dealing with a pannus of synovial origin. The possibility of a local transformation of chondrocytes into fibroblasts, is also discussed. The earlier reports concerning the occurrence of arthrosis in combination with pannus, are contradictory. We suggest that coxarthrosis can occur both with and without pannus. These two possibilities may represent different forms of arthrosis.