Bisphosphonates reduce the risk of fractures associated with osteoporosis but increase the risk of atypical subtrochanteric femur fractures. After unilateral atypical femur fracture, there is risk of contralateral fracture, but the indications for prophylactic fixation are controversial.

Questions/purposes The purpose of this study is to use Markov modeling to determine whether contralateral prophylactic femur fracture fixation is cost-effective after a bisphosphonate-associated atypical femur fracture and, if so, what patient-related factors may influence that determination.