Explanation:
Antegrade intramedullary interlocking nailing is the gold standard for closed diaphyseal femur fractures in stable patients. It provides biomechanical stability, allows early mobilization, and has lower rates of malunion compared to traction or plating. Skeletal traction is obsolete as definitive care. Plates have higher soft tissue disruption. External fixation is reserved for damage control in unstable patients. References: Rockwood and Green’s Fractures in Adults; Campbell’s Operative Orthopaedics.