Fig. 7.

Hip joint disease. Axial fat saturated T1-weighted MR image after IV Gd and axial STIR MR images. (a) Hip arthritis in a 13-year-old boy shows a joint effusion in the left hip joint with synovial enhancement (arrow) (b) Avascular necrosis (AVN) in a 17-year-old-boy demonstrates discrete T2 hyperintense signal changes in the femoral head on the right side (arrow), AVN was suspected and confirmed. (c) Radiography of the pelvis in the same patient one year later also confirmed the diagnosis of AVN. There is a subchondral fracture, subchondral sclerosis and flattening of the femoral head on the right side (arrow).