Buttress and stretch effect of internal fixation for femoral intertrochanteric fractures / 中华骨科杂志

ABSTRACT

Intertrochanteric fractures of femur are common osteoporotic fractures in the elderly, and internal fixation is the preferred treatment method. The purpose is to use internal fixators to share the load conducted by the hip joint. Most of the current researches focus on theories of the lateral wall, medial wall, apex distance, and ratchet mechanism etc of the proximal femur. However, neither the extramedullary nor the intramedullary designs of single head-neck screws or double head-neck screws based on these theories can completely avoid the occurrence of femoral head penetration. According to the distribution of trabecular bone in proximal femur and the biomechanical change characteristics before and after fracture, the lever-balance reconstruction theory was proposed, and the therapy clarified the dynamic changes of stress on head-neck screws after internal fixation. On the basis of this theory, the author further proposed the buttress and stretch effect that affected the stability of internal fixation of femoral intertrochanteric fractures, and clarified the causes and mechanisms of internal fixation screw penetration of femoral head after fracture operation. In view of this effect, it is recommended to use proximal femoral bionic nail (PFBN) for the treatment of femoral intertrochanteric fractures to prevent the screw from penetrating the femoral head, providing a new idea for the internal fixation of intertrochanteric fractures in the future.