Proximal femoral nail anti-rotation (PFNA) with a lag screw that is shaped like a spiral blade shape is an orthopedic implant to fix trochanteric fractures of the proximal femur. In addition the reason of the biomechanical advantages, PFNA widely been used recently. We report an 83-year-old man with excessive sliding of the helical blade and a femoral neck fracture after AO/OTA type A2 intertrochanteric fracture, which was fixed with a PFNA.