Pubic osteolysis mimicking a malignant lesion: report a case with a fracture dislocation of the sacroiliac joint.

We report the case of a 67-year-old woman who presented to our institution with osteoblastic and osteolytic lesions of the pubis and fracture dislocation of the left sacroiliac joint. She had presented 7 months earlier to an outside institution with a left gluteal mass, which had been biopsied and had been believed to represent malignancy. A second biopsy at our institution showed no evidence of malignancy and was felt to represent fracture healing. A diagnosis of public osteolysis was made based on the radiographic and histologic findings. A follow-up radiograph 6 years after presentation revealed healing of the lesions, confirming its benignity.