Purpose: Although injury of the lateral femoral cutaneous nerve (LFCN) is a known complication after total hip arthroplasty (THA) via the direct anterior approach (DAA), the impact of this complication on postoperative quality of life (QOL) is unclear. This study aims to investigate the incidence of LFCN injury after DAA for THA, and to determine the impact of LFCN injury on QOL and hip function.
Methods: We prospectively investigated 122 hips operated upon using the DAA regarding the incidence of LFCN injury using self-reported questionnaires, hip functional scores such as the Harris Hip Score (HHS) and the Japanese Orthopaedic Association (JOA) score, and patient-reported outcomes such as the Western Ontario and McMaster Universities Osteoarthritis Index, the Japanese Orthopaedic Association Hip disease Evaluation Questionnaire (JHEQ), and the Forgotten Joint Score-12 (FJS).
Results: LFCN injury was seen in 39 hips (31.9 %). In affected hips, the leading symptom was hypo-aesthesia (46.2 %), followed by tingling or jolt-like sensation (28.2 %). There was no difference in the HHS and JOA score between those with LFCN injury and those without. There was a significant difference in the FJS-12 between the two groups (50.9 ± 25.3 for hips with LFCN injury vs 64.3 ± 25.7 without, p = 0.01). There was a non-significant tendency for patients with LFCN injury to have a lower JHEQ than those without (63.6 ± 19.6 for hips with LFCN injury vs 70.8 ± 22.9 without, p = 0.13).
Conclusions: The incidence of LFCN injury decreased QOL but not hip function after DAA for THA.
Keywords: Direct anterior approach; Forgotten joint score; JHEQ; Lateral cutaneous femoral nerve; Patient reported outcomes; Quality of life.