Figure 1

Distribution of 117 bone marrow oedema (BME)/avascular osteonecrosis (AVN)-affected bones (98 joints) and Association Research Circulation Osseous (ARCO) stages according to roentgenological and MRI-based diagnosis. Before treatment with iloprost the hip joint was affected in 43%, followed by foot joints in 28%, the knee joint in 26% and the shoulder in 3%. The initial ARCO distribution was as follows: No ARCO 0, 82 ARCO I, 20 ARCO II, 13 ARCO III and two ARCO IV.