[Simultaneous existence of unicameral bone cysts involving the femur and ischium].

We report a 30-year-old male patient with two unicameral bone cysts (UBC) simultaneously located in the proximal third of the right femur and ipsilateral ischium ramus, respectively. Fine needle biopsies were attempted for both lesions. Biopsy of the femoral lesion under local anesthesia was unsuccessful, so an open biopsy was performed which confirmed the diagnosis of UBC. Biopsy of the ischial lesion was not sufficient for diagnosis. Cytological examination of both specimens showed no other benign or malignant pathology. The femoral lesion was treated with intralesional (due to its large size) excision-curettage, bone grafting, and the introduction of a long gamma locking intramedullary nail to prevent the occurrence of a pathological fracture. The ischial lesion was left untreated and followed conservatively. The patient was free of any symptoms and complications three years postoperatively. This is the first report of an adult patient with UBCs simultaneously located both in a long tubular bone (femur) and a flat bone (ischium ramus).