PAPAIN-INDUCED DEGENERATIVE ARTHRITIS OF THE HIP IN RABBITS

Abstract

1. Degenerative arthritis has been produced consistently in adult rabbits by the injection of the proteolytic plant enzyme papain into the hip joint. Arthritic changes were recognisable radiographically after six weeks. 2. A progression of changes occurred, from loss of acid mucopolysaccharide staining in the matrix, fibrillation, fissuring and erosion of articular cartilage with death of chondrocytes in the weight-bearing areas, to secondary bony changes of subchondral sclerosis, occasional cysts and osteophyte formation. 3. Synovial inflammation occurred with accumulation of cartilage and bone debris in the inferior capsule and later capsular thickening. 4. It is suggested that this arthritis is sufficiently similar to human osteoarthritis to be useful as a model for further studies of the pathogenesis of the disease and the effects of different methods of treatment.