A large multiloculated osteochondroma arises from the posterior right iliac crest, with a small portion extending into the superior portion of the sacroiliac joint, but the main part extends to the lateral right paraspinal muscles. The cartilage cap is identified on all portions and measures no more than 5 mm thick. Post contrast administration, patchy enhancement within the osseous component of the osteochondroma particularly posteriorly, is of uncertain significance. No fracture of the osseous component (including the stalk) and no bursa is seen. There is no soft tissue mass. Degenerative change is seen in the right sacroiliac joints with small subchondral cysts formed inferiorly. No mass is seen in the pelvis. A cyst anterior to the right ovary is likely to be functional.