Bilateral Atypical Femur Fractures After Denosumab in a Bisphosphonate Naive Patient: A Case Report

A case report of bilateral atypical femur fractures (AFF) in a bisphosphonate naive patient. A 62-year-old female bisphosphonate naive patient was started on denosumab for osteoporosis. Approximately 3 years later she complained of right hip pain and was found to have a bilateral incomplete AFFs. She was asymptomatic on the left lower limb. Patient was managed conservatively and placed on protected weight bearing on both legs. Symptoms subsequently resolved over a period of 3 months, although radiographic findings remained at approximately 1 year. AFFs may be associated with patients on denosumab therapy even without a prior history of bisphosphonate use. Patients should be counselled appropriately and monitored for such complications.