Atypical Femoral Fractures — Are They Associated with Bisphosphonate Therapy, and Why Should a Dermatologist Care?

Atypical fractures of the femur have been reported in recipients of bisphosphonate therapy, but causality and the extent of risk are controversial. Conflicting studies have found both no association and an increased risk (particularly with more than 5 years of use). Bisphosphonates now carry label warnings about atypical fractures.

Researchers reviewed the records of 477 patients aged 50 years or older who were treated for subtrochanteric or femoral shaft fractures over a period of 10 years at a single Swiss center. Of these patients, 39 had atypical fractures (0.7% of all femur fractures), 32 of whom had received bisphosphonate therapy (82.1%). Of the 438 patients with characteristic femoral fractures, 28 had a history of bisphosphonate use…