Peri-implant Atypical Fractures Associated with Bisphosphonates: Should this Clinical Entity be Included in the Definition of Atypical Femoral Fracture? Case Report

INTRODUCTION: In recent years, growing evidence of the association between bisphosphonate use and incidence of atypical femoral fractures has emerged. Cases of peri-implant fractures associated with bisphosphonate use suggest the emergence of a new clinical entity because they are not currently covered by the definition of atypical femoral fracture. CASE REPORT: We present here two rare clinical cases treated in our hospital. Two women (68 and 76 years old) with peri-implant (cephalomedullary nail) fractures and history of prolonged bisphosphonate use (11 and 14 years). Both fractures occurred after minor trauma and showed an atypical fracture pattern. One of the patients underwent revision osteosynthesis and had a 12 months follow-up. The second patient was submitted to orthopedic treatment and had a 6months follow-up. CONCLUSION: Although reports of periprosthetic fractures and peri-implant(plate and screws) have been published, references to peri-implant cephalomedullary nail fractures were not found in the literature. Here, we question if these fracture types should be included in the current definition of atypical femoral fracture, or form a new clinical entity.