Nerve Injuries After Total Knee Arthroplasty: A Systematic Review and Meta-Analysis

Background Nerve injury is an uncommon but clinically meaningful complication following total knee arthroplasty (TKA). Reported incidences vary widely across the literature, and the specific patterns, predictors, and recovery trajectories remain unclear. This systematic review and meta-analysis aimed to determine the prevalence, types, risk factors, management approaches, and recovery outcomes of nerve injuries after TKA. Methods A comprehensive search identified eight eligible studies reporting postoperative nerve injuries following primary or revision TKA. Data extracted included patient demographics, surgical and perioperative characteristics, nerve injury types, management strategies, and recovery outcomes. Random-effects models were used to pool incidence and recovery proportions. Meta-regression evaluated demographic and procedural predictors, while sensitivity analyses assessed robustness. Publication bias was examined using funnel-plot visualization. Results Across 1,599,948 TKAs, 4,746 nerve injury events were identified. The pooled incidence was highly variable, with a random-effects estimate of 12.86% and substantial heterogeneity (I² = 99.6%). The common peroneal nerve accounted for the majority of injuries, while tibial, femoral, sciatic, and saphenous nerve injuries were less frequent. Demographic factors such as age, sex, BMI, comorbidities, and preoperative deformity were not significant predictors (p > 0.05). Among procedural factors, only tourniquet use was significantly associated with increased nerve injury risk (p = 0.0136). Overall recovery was favorable, with a pooled recovery rate of 73% (I² = 86.4%). Time to full recovery ranged from approximately 10 to 22 months. Conservative management was the mainstay, with selective surgical intervention for compressive etiologies. Funnel-plot asymmetry suggested potential publication bias. Conclusion Nerve injury after TKA remains uncommon but clinically significant, with the common peroneal nerve most frequently affected. Tourniquet use appears to be the key modifiable risk factor. Most patients recover function, though recovery may be prolonged. Further standardized prospective research is needed to refine prevention and management strategies.