End-stage osteoarthritis of the hip joints of the 15-year-old patient with MED type 4. Anteroposterior radiograph of the hips: abnormal shape and structure of the epiphysis of the femoral head on the right side—half-moon shape (white arrow), secondary reduced size of the epiphysis and narrowing of the joint space on the left side (black arrow), secondary deformity of the acetabulum—doubled “seagull-like” contour (black lines).