Surgical Fixation of Atypical Femur Fractures in Bisphosphonate-treated Patients.

Objective To evaluate the outcomes of the surgical fixation of atypical femoral fractures in bisphosphonate-treated patients with an intramedullary device. Materials and methods This multicentric study was carried out at the department of orthopedics, Dr. Ruth Phau Civil Hospital and Medicare Hospital, Karachi, Pakistan, between 2013 and 2018. In this retrospective observational study, we reviewed 10 bisphosphonate-treated patients, fixed surgically with an intramedullary nail after presenting with radiologically characteristic atypical femur fractures identified according to the American Society for Bone and Mineral Research criteria. We excluded patients with fractures sustained by high-energy trauma, road traffic accidents, fall from a height, and those associated with underlying malignancy. Results A total of 11 atypical femoral fractures in 10 patients were included, all of whom were females with a mean age of 68.6 (range 57-82) years. Out of 11 fractures, 81.8% (n=9) were located in the subtrochanteric region and two were located in the femoral shaft. The mean bisphosphonate use was 58.3 months. All patients were treated with intramedullary devices; an intramedullary interlocking nail in two cases and proximal femoral nail antirotation in nine cases. The mean follow-up duration was 12 months. All fractures were united in an average time of 9.9 months (range 6 - 16 months). Implant failure and/or nonunion were not observed, whereas delayed union was noted in five patients. Conclusion Intramedullary fixation is a reliable method for the treatment of atypical femur fractures in bisphosphonate-treated patients owing to its intramedullary placement. These devices act as an internal splint and can provide much more axial stability, reducing the risk of implant fatigue failure due to a delay in fracture healing from prolonged bisphosphonate use.