Isolated ACL Reconstruction Versus Combined ACL and Anterolateral Ligament Reconstruction: Functional Outcomes, Return to Sport, and Survivorship: An Updated Meta-analysis of Comparative Studies

Background: Failure, persistent knee instability, and reinjury rates after anterior cruciate ligament (ACL) reconstruction are still concerns. Biomechanical investigations have highlighted the role of the anterolateral ligament (ALL) as a crucial knee stabilizer, and clinical outcomes after combined ACL and ALL reconstruction appear to indicate the success of the procedure. Purpose: To compare the functional outcomes, return-to-sport (RTS) rate, and complications between combined ACL and ALL reconstruction and isolated ACL reconstruction. Study Design: Meta-analysis; Level of evidence, 4. Methods: The PubMed/MEDLINE, Scopus, and Cochrane Central databases were used to search keywords, and a total of 16 studies were included. The data extracted for quantitative analysis included the Tegner activity scale score, Lysholm knee score, International Knee Documentation Committee (IKDC) score, laxity measured using the KT-1000 knee arthrometer, number and types of complications, RTS rate, and survival rate. Random- and fixed-effects models were used for the meta-analysis of pooled mean differences and odds ratios. Results: A total of 2329 patients were identified, 1116 of whom underwent combined ACL and ALL reconstruction and 1213 of whom underwent isolated ACL reconstruction. The mean ages were 25.4 ± 7.2 years and 26.5 ± 7.8 years for the combined ACL and ALL reconstruction and isolated ACL reconstruction groups, respectively. The mean follow-ups were 40.3 ± 21.4 months and 42.5 ± 21.6 months, respectively. Comparable Tegner activity scale ( P = .16), Lysholm knee ( P = .13), and IKDC ( P = .83) scores were found between groups. Significantly greater postoperative knee laxity was found in the isolated ACL reconstruction group (mean difference, –0.44; 95% CI, –0.85 to −0.04; P = .03). The combined ACL and ALL reconstruction group showed a significantly lower rate of graft failure (odds ratio [OR], 0.37; 95% CI, 0.18-0.77; P = .008), a higher RTS rate (OR, 1.41; 95% CI, 1.11-1.80; P = .005), and a higher survival rate (OR, 2.94; 95% CI, 1.97-4.37; P < .001). Conclusion: Compared with isolated ACL reconstruction, combined ACL and ALL reconstruction yielded comparable functional outcomes but significantly less residual knee laxity and a lower graft failure rate. Patients who underwent combined ACL and ALL reconstruction also had higher RTS and survival rates.