Finite element analysis of the influence of femoral neck system implantation angle on biomechanical stability in femoral neck fractures: a mechanistic exploration

The biomechanical performance of the FNS is fracture-type-dependent, necessitating angle-specific optimisation. For Pauwels type I/III fractures, optimal nail placement at 130° enhances stress distribution, whereas type II fractures may benefit from 120° angulation. These findings underscore the criticality of intraoperative angle control in mitigating fixation failure and non-union risk. Future studies should incorporate clinical follow-ups and multi-axis loading to validate these biomechanical insights.