Radiological vignette. Insufficiency fracture of the acetabulum.

An insufficiency fracture (IF) involving the acetabulum is presented. This fracture occurred in a 67-year-old woman who had been hysterectomized and oophorectomized 27 years earlier for a carcinoma of the uterine cervix, and who had received external pelvic irradiation. This IF location has been rarely described earlier, and its awareness should preclude unnecessary aggressive diagnostic procedures especially in patients with osteoporosis and previous pelvic radiotherapy.