Bisphosphonate associated femoral stress fracture distal to an orthopaedic implant: They are predictable!

Abstract

Stress fractures are uncommon and often occur in young athletes with high intensity physical activity. These stress fractures occur in weight bearing long bones. Recent literature suggests association of thigh pain, tension side cortical thickening of femoral shaft or a femoral subtrochanteric atypical stress fractures in patients on long term bisphosphonate therapy. The reports of peri-implant bisphosphonate associated atypical stress fractures are very rare. We describe a series of three cases of femoral shaft stress phenomenon around orthopaedic implants who presented with similar prodromal thigh pain and tension side cortical thickening. Two patients sustained fractures as the condition was not recognised despite presenting with prodromal symptoms and one patient with a stress riser who was treated prophylactically. Thus this series aims to highlight the importance of identifying the stress phenomenon around orthopaedic implants, be it intra or extra-medullary implants. The location of these fractures is just distal to the implants and are classically transverse fractures. The treatment of peri-implant stress fractures needs a personalised approach in every case with appropriate choice of implants.