Fig. 1.
Anteroposterior radiograph of the pelvis in a 27-year-old man, showing erosions of the right sacroiliac joint and demarcation of the cortex of the right ischial tuberosity
Anteroposterior radiograph of the pelvis in a 27-year-old man, showing erosions of the right sacroiliac joint and demarcation of the cortex of the right ischial tuberosity