Concomitant Anterior Cruciate Ligament and Medial Collateral Ligament Reconstruction: A Systematic Review

Concomitant anterior cruciate ligament (ACL) and medial collateral ligament (MCL) injuries are among the most commonly reported injury patterns in high-energy knee injuries. Concomitant ACL and MCL reconstruction (ACLR + MCLR) is indicated in patients with full-thickness tears and persistent valgus laxity.

To systematically review the literature to identify studies reporting on patients undergoing concurrent primary ACLR + MCLR to better understand current indications, surgical techniques, complications, and outcomes.

Systematic review; Level of evidence, 4.

Under the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, 702 studies published in PubMed, EMBASE, and the Cochrane Library reporting on patients undergoing ACLR + MCLR from inception to April 2025 were initially identified. The inclusion criteria included studies reporting on human subjects undergoing ACLR + MCLR with injury mechanism, tear characteristics, surgical technique, graft types used for reconstruction, complications, and postoperative outcomes. Incidence rates for variables of interest were pooled as proportions with inverse variance weighting and displayed in forest plots, with heterogeneity of included studies assessed using the I ² statistic.

Seventeen studies, including 902 patients undergoing concurrent ACLR + MCLR, with a mean follow-up of 30.6 months (range, 15-61 months), were identified. The weighted mean patient age was 32.9 years (range, 14-74 years), and 68.4% (n = 471/689) of patients were men. Sports-related traumatic knee injuries accounted for 51.3% (n = 309/602) of injuries, while motor vehicular accidents comprised 12.1% (n = 73/602). Reported indications for MCLR in the setting of ACL injury were chronic (≥6 weeks) valgus knee laxity despite nonoperative management (81.5%, n = 667/818) and grade 3 MCL injury (22.2%, n = 182/818). Autografts were utilized in 69.7% (n = 265/380) of ACLR and 61.1% (n = 140/262) of MCLR procedures, while anterior tibialis allografts (28.4%; n = 108/380) and hamstring tendon autografts (53.4%; n = 140/262) were the most frequently reported graft types in ACLR and MCLR, respectively. Complications were reported in 14 cases, including persistent medial knee pain (n = 7) and reconstruction failure (MCLR, n = 1; ACLR, n = 2). Mean Lysholm scores improved from 55.9 to 87.6, while mean Tegner and subjective International Knee Documentation Committee (IKDC) scores improved from 3.1 to 4.8 and 46.5 to 88.5, respectively.

Our review revealed that concomitant ACLR + MCLR is most commonly performed for injuries sustained during pivoting sports, which result in persistent valgus laxity. Autografts were used in 70% of ACLR and 61% of MCLR procedures. Improvements in Lysholm, Tegner, and IKDC scores were noted in the majority of patients with a low incidence of complications (7.9%) and reconstruction failures (1.7%). These findings may enhance the understanding of proper surgical indications and methodology, thereby optimizing treatments and postoperative outcomes.