Multi-lobulated osseous mass, the medullary cavity of which is continuous with the superior aspect of the right iliac crest, just next to the sacroiliac joint is present. The largest component extends into the lateral right paraspinal muscles. A large soft tissue mass is not seen. No fracture of the lesion is detected. There is degenerative change in the right sacroiliac joint, with subchondral cysts formed inferiorly.