The typical radiographic characteristics of osteoarthritis include ( Fig. 48.1 ). Asymmetric joint space narrowing - This indicates loss of articular cartilage. For example, the hip migrates superiorly because of the loss of cartilage superiorly along the weight-bearing surface. Subchondral sclerosis ( also called eburnation ) - This is caused by trabecular compression and fracture with callus formation. Osteophyte formation.