Insufficiency fractures are stress fractures that occur from normal weight-bearing on weakened bone. Radiation treatment to malignancies in the prostate, rectum, anus, or cervix may increase the risk of insufficiency fractures in the pelvic region by damaging osteoblasts that are essential to bone formation. In elderly women with cancer, this risk is greater due to their susceptibility to developing osteoporosis. These fractures may be confused with pathological fractures resulting from bone metastases on imaging and should be identified for proper management. We report two cases in which two women developed painful insufficiency fractures in the pelvic region after receiving radiation treatment to the rectum. After consulting an orthopedic surgeon, one patient underwent a cementoplasty, while the other patient was encouraged to take bone strengthening medications.
Keywords: Bone metastases; insufficiency fracture; radiotherapy.