A case of calcifying tendinitis of the insertion of the gluteus maximus tendon is presented. Plain-film roentgenograms showed amorphous calcific densities extending from the posterior border of the femur. Computed tomography showed cortical erosion associated with the calcified mass. The patient responded well to needle lavage and injection with local anesthesia and corticosteroids. Fifteen-month follow-up roentgenograms showed resolution of the calcification. Recognition of this entity may make a workup and a biopsy unnecessary.
