[The evolution and practice on design concepts of internal fixation devices for intertrochanteric femur fractures].

Surgical treatment has been established as the standard method for the treatment of intertrochanteric fractures in the elderly. The design of internal fixation devices has become the key to improve surgical outcomes and reduce postoperative complications. Centered on optimizing biomechanical performance and minimally invasive implantation, coupled with continuous material improvements, the design philosophy of internal fixation devices has also been constantly evolving. There have been several milestone advancements, such as the transition from eccentric fixation to central fixation, the adoption of sliding compression fixation, the replacement of traditional screws with spiral blades, and the shift from single to double (combination) nails. However, the incidence of internal fixation-related complications has remained at a relatively high level of 5% to 10%, without significant breakthroughs. Increasing evidence suggests that in-depth analysis of the anatomy, physiological mechanisms, and mechanical transmission characteristics of the proximal femur can help elucidate the root causes of internal fixation failures. Based on this, the proximal femoral bionic nail (PFBN) has emerged as a new design concept. By fully mimicking the anatomical, mechanical, and biological characteristics of the proximal femur, the PFBN can regulate the local mechanical environment, providing a revolutionary solution and a new approach for the treatment of proximal femoral fractures. This innovative design also has the potential to drive the paradigm shift in the treatment strategies of other fractures.