Synthetic augmentation in ACL reconstruction may reduce re-rupture rates and increase return-to-sport rates: A systematic review and meta-analysis.

Abstract

Synthetic augmentation (SA) in anterior cruciate ligament reconstruction (ACLR) aims to enhance graft durability, but its benefits remain unclear. To evaluate whether SA in ACLR improves return-to-sport (RTS) rates, reduces graft failure, enhances patient-reported outcomes (PROs) and varies in effectiveness across materials and techniques. A systematic search of five databases was conducted until February 2025. Comparative studies were pooled using Hedges' random-effects meta-analysis with subgroup analysis based on materials and publication year. Non-comparative studies were analysed narratively. Risk of bias was assessed using the Risk of Bias in Non-randomised Studies of Interventions and the Cochrane risk-of-bias tools for randomised studies. Grades of Recommendation, Assessment, Development and Evaluation (GRADE) approach was used to assess the certainty of evidence. Forty-seven studies were included (n = 4289): 7 randomised and 40 non-randomised studies (21 comparative; 19 non-comparative). SA systems included InternalBrace (FiberTape, 16 studies), Ligament Augmentation and Reconstruction System (polyester, 5), Ligament Augmentation Device (polyethylene, 18) and other materials (8). GRADE assessment showed moderate-certainty evidence for improved mid-term RTS rate from eight studies (odds ratio [OR]: 1.58; 95% confidence interval (CI): 1.12-2.22; N = 716; I² = 0%; p = 0.01). Internal brace showed a reduction in re-rupture rates in the long-term (OR: 0.17, 95% CI: 0.04-0.64; N = 218; I² = 0%; p = 0.01); however, pooled analysis of all techniques showed no statistically significant difference. Contemporary studies showed a better return to sport rates with SA. PROs showed no clinically meaningful differences. Non-comparative studies showed low graft failure rates (<8.7% for InternalBrace; <16.4% for other SA), high RTS rates (>90% for InternalBrace; >56.7% for other SA) and satisfactory PROs. SA, particularly InternalBrace, may improve RTS rates and reduce re-rupture risk, though PROs remain inconclusive. Findings are limited by a moderate-to-serious risk of bias, emphasising the need for high-quality research. Level III.