Treatment of Femoral Fracture Nonunion After Long-term Bisphosphonate Use

Bisphosphonates are a class of drugs that prevent bone loss by decreasing bone resorption. They represent a major treatment for osteoporosis and other metabolic bone diseases. Recent reports suggest that a potential complication of long-term bisphosphonate therapy may be atypical insufficiency fractures of the femur. Concern exists about delayed union after fracture stabilization in patients taking bisphosphonates. This article describes 2 patients on long-term bisphosphonate therapy treated for atypical femur fractures that failed to heal with intramedullary nailing. Both patients' fractures occurred after at least 4.5 years of bisphosphonate use and displayed classic findings of bisphosphonate fractures reported in the literature, including a subtrochanteric location, presentation after minimal trauma, transverse fracture, no comminution, and cortical beaking. The original fractures were treated at other institutions with intramedullary nails. Subsequently, both patients presented with pain and atrophic nonunion of their fractures. Evaluation included a computed tomography scan of the fracture and a metabolic workup. The patients discontinued bisphosphonate therapy. They were treated with nail removal and definitive plating to achieve compression across the fracture site. Both fractures went on to heal after this treatment with no further complications. The literature currently recommends treating bisphosphonate fractures with an intramedullary nail. Perhaps initial treatment of these fractures should be similar to an atrophic nonunion, involving compression plating to obtain bone-on-bone contact and promote healing. This would address the biologic and mechanical etiologies of the bisphosphonate fracture.