Femur shaft fracture following osteoid osteoma radiofrequency ablation.

INTRODUCTION: Radiofrequency ablation is an effective modality in treating osteoid osteoma while avoiding the complications of an open procedure. Its complications are usually self-limited consisting mostly of local skin burns. This report presents a major complication, a femur shaft fracture following an osteoid osteoma radiofrequency ablation. The fracture occurred approximately one year after the ablation at the site of the osteoid osteoma.

DISCUSSION: Few case reports have been published regarding subtrochanteric femur fracture after ablation of an osteoid osteoma. To our knowledge this is the first report of a femoral shaft fracture following an ablation. Another unique characteristic of the presented case is the late presentation, approximately one year following ablation. Factors which may have contributed to the fracture include lateral entry point of the drill which may have weakened the femur when taking its biological and mechanical properties into account, and the fact that the patient was a soldier who was allowed to continue his military training only six weeks after the ablation.

CONCLUSION: Radiofrequency ablation is an effective and relatively safe technique in treating osteoid osteomas, however the physician should be aware of the fracture risk involved, consider mechanical and biologic factors of the bone prior to drilling, and be very conservative when recommending return to high level activity. In addition, a close follow-up should be carried on after the procedure in order to supervise bone remodeling.