Two Cases of Atypical Femoral Fractures after Bisphosphonate Therapy

Abstract

Bisphosphonate therapy decreases the risk of vertebral and proximal femoral fractures in patients with osteoporosis. However, recent reports have associated long-term bisphosphonate therapy with atypical femoral fractures. We report two cases of atypical femoral fracture in patients receiving bisphosphonate therapy. One patient had ipsilateral femoral pain before fracture, and the other did not. Both patients showed cortical thickening, short oblique orientation, medial spikes, minimal trauma, and absence of comminution. The association between bisphosphonate therapy and the occurrence of atypical fractures of the femur is highly likely. However, the incidence rate was very low. The need for continued bisphosphonate therapy should be carefully reassessed.