Femoral nerve palsy following total hip arthroplasty via posterolateral approach: a report of two cases and literature review

Femoral nerve palsy is a rare but serious complication following total hip arthroplasty (THA), particularly when performed through the posterolateral approach. Early diagnosis and prompt rehabilitation are crucial for functional recovery. We report two cases of femoral nerve palsy following THA, highlighting the clinical course, management, and outcomes. The first case involved a 53-year-old male with ankylosing spondylitis that underwent right-sided uncemented THA via the posterolateral approach. Postoperatively, he developed femoral nerve palsy, likely due to skin traction applied for residual hip flexion contracture. Early removal of traction, initiation of physiotherapy, and use of a static knee brace led to gradual recovery, with full restoration of quadriceps function by one year. The second case involved a 46-year-old obese female with a history of hip tuberculosis who underwent uncemented THA via the posterolateral approach. She developed femoral nerve palsy immediately postoperatively, likely related to intraoperative retractor placement difficulties due to tight soft tissues. Early mobilization and physiotherapy led to complete recovery of quadriceps strength within six months. Femoral nerve palsy, though uncommon after posterolateral THA, can significantly impact postoperative recovery. Awareness of risk factors such as soft tissue tightness and traction, combined with early diagnosis, rehabilitation, and supportive bracing, can lead to favorable outcomes. Surgeons must be cautious during soft tissue handling and retractor placement to minimize this complication.