Pathologic femur fractures following surgery and radiotherapy for soft tissue sarcomas: A case series

Combined limb-sparing surgery and radiation therapy are considered the standard of care for higher grade soft tissue sarcomas (STS) of the extremities. The risk of post-radiation fracture after this treatment modality is well known, but still underestimated, and can end in serious long-term secondary problems years later.

We reviewed the records of three patients with pathological femur fractures years after wide local excision of an STS of the proximal lower extremity. All patients received more than 50 Gy (Gy) to the entire femur circumference. During surgery, all patients had bone exposure, and in two patients with stripping of the periosteum. The median time from surgery to fracture was 116 months (range from 84 to 156 months). The median age at the time of diagnosis was 66 years old. Despite standard operative fracture treatment, all three patients developed a non-union. One patient later died due to uncontrolled pulmonary metastasis independent from the femoral non-union. In the second case, an exarticulation at hip level due to an uncontrolled infected non-union had to be performed. The third patient finally achieved fracture union after two years of treatment.

Our study confirms the high occurrence rate of postoperative complications and difficulties one encounters in treating these pathologic fractures. Only in one patient, following several revisions with intramedullary nailing, the fracture healed. In pathologic femur shaft fractures we recommend a minimal invasive procedure using intramedullary nailing devices.

The risk of pathological fractures at the former treatment site is high, even years later. The rate of non-unions after a difficult fracture treatment in this particular clinical situation seems to be very high and may be associated with severe complications.