Growth disturbances in experimental juvenile arthritis of the dog knee.

In the study of pathophysiological mechanisms in growth abnormalities of the juvenile knee in arthritis an animal model in dogs was developed. Arthritis was induced by intra-articular injections of Carrageenan. Prominent growth changes were enlargement of the distal femoral epiphysis, patellar squaring and decreased endochondral and appositional growth of the distal femur. Generalized osteoporosis of the arthritic limb was present. The induced growth disturbances bear resemblance to the growth abnormalities in juvenile chronic arthritis and hemophilic arthropathy of the knee.