RESUMO
Early internal fixation for intertrochanteric fracture of the femur can improve the quality of patients′ life and reduce disability and mortality. In the past, treatment of intertrochanteric fracture of the femur had some problems, such as head and neck screw cut-out, hip varus deformity, nail withdrawal, femoral neck shortening, and internal fixator fracture, etc., for which no reasonable explanation could be provided. The "lateral wall" theory has been recognized by most scholars and used to guide the development and clinical application of internal fixation, which has not entirely avoided the occurrence of the complications mentioned above. A correct understanding of the mechanics of the lateral wall of the proximal femur helps choose a reasonable internal fixation method for the treatment of intertrochanteric fracture of the femur to reduce the incidence of complications. The author firstly discusses the lateral wall measuring and fixation strengthening methods, reasonably explore the reasons for postoperative complications according to the theory of lever-pivot balance, and proposes that the proximal femoral bionic nail (PFBN) is an ideal choice for the treatment of intertrochanteric fracture of the femur.