Double-Bundle Anterior Cruciate Ligament Reconstruction Provides Superior Short-to-Midterm Rotational Stability But Not Clinically Important Functional Gains Over Single-Bundle: A Systematic Review and Meta-analysis.

Abstract

Purpose: To compare the biomechanical and functional outcomes between single-bundle and double-bundle (DB) anterior cruciate ligament reconstruction techniques using the most current evidence, stratified by follow-up duration.

Methods: PubMed, Embase, and Cochrane databases were searched from 2013 to September 2025 for randomized controlled trials comparing single-bundle versus DB anterior cruciate ligament reconstruction with a minimum follow-up of 24 months. Primary outcomes included anterior tibial translation, rotational stability (pivot shift), and patient-reported outcomes (subjective International Knee Documentation Committee, Lysholm score). Secondary outcomes included return-to-sport and graft failure rate. Continuous outcomes were pooled using inverse-variance random-effects models (DerSimonian-Laird) and dichotomous outcomes using Mantel-Haenszel fixed-effect models, with stratification by follow-up duration (24-48 months vs >48 months). Heterogeneity was assessed using the I ² statistic.

Results: Thirteen randomized controlled trials (1041 patients; 536 single-bundle, 505 DB; mean age 30.2 years; 68% men; follow-up 24-122 months) were included. At 24 to 48 months, DB reconstruction significantly reduced the risk of a positive pivot shift (risk ratio 0.60, 95% confidence interval [CI] 0.43-0.84, P = .003; number needed to treat = 10) and showed statistically higher subjective International Knee Documentation Committee (mean difference 5.88 points, 95% CI 0.44-11.33) and Lysholm (mean difference 7.47 points, 95% CI 0.06-14.88) scores; however, neither reached established minimal clinically important difference thresholds (11.5 and 8.9 points, respectively). Anterior tibial translation did not differ significantly between techniques (mean difference -0.34 mm, 95% CI -1.04 to 0.35, P = .327). No study reported sex-disaggregated outcomes or individual-level minimal clinically important difference attainment. Beyond 48 months, no significant differences were observed for any outcome.

Conclusions: DB reconstruction shows statistically significant improvements in rotational stability and patient-reported functional scores at 24 to 48 months, but functional differences do not reach established minimal clinically important difference thresholds. No significant differences were observed beyond 48 months, a finding likely influenced by substantial study heterogeneity and graft selection. The current evidence does not support a universal clinical advantage for the DB technique; shared decision-making based on patient activity demands and surgeon experience remains essential.

Level of evidence: Level I, systematic review and meta-analysis of randomized controlled trials.