The chief pathologic features of osteoarthritis are a. stress fractures of the epiphysis, inflammation of the diaphysis, and accumulation of excessive synovial fluid. b. degeneration of articular cartilage, destruction of the bone under the cartilage, and thickening of the synovium. c. thinning of the joint capsule, resorption of bone, excessive formation of new bone, and formation of bone spurs. d. autoimmune damage to the synovium, destruction of articular cartilage by pannus, and thickening of synovial fluid.