Clinical Outcomes of Primary Anterior Cruciate Ligament Reconstruction With Concomitant Lateral Meniscal Posterior Root Tear Repair Versus Isolated Anterior Cruciate Ligament Reconstruction: A Systematic Review and Meta-Analysis.

INTRODUCTION: Lateral meniscal posterior root tears (LMPRTs) commonly occur with anterior cruciate ligament (ACL) injuries, but clinical outcomes after concomitant repair remain unclear. AIM: This systematic review and meta-analysis compared postoperative outcomes after ACL reconstruction (ACLR) with concomitant LMPRT repair versus isolated ACLR with an intact lateral meniscus and summarized available evidence comparing repair with nonrepair. EVIDENCE REVIEW: MEDLINE, Embase, and CENTRAL were searched from inception to May 23, 2026. Comparative studies evaluating primary ACLR with concomitant LMPRT repair versus isolated ACLR with an intact lateral meniscus or untreated LMPRT with at least 1-year follow-up were included. The methodological quality of all included studies was assessed using the Methodological Index for Non-Randomized Studies (MINORS). Meta-analyses calculated pooled mean differences (MDs) with 95% confidence intervals (CIs) for patient-reported outcomes and objective stability using random-effects models. Outcomes not suitable for quantitative synthesis were summarized descriptively. FINDINGS: Nine retrospective comparative studies comprising 910 knees (340 ACLR with LMPRT repair and 570 comparators) were included. Seven studies used isolated ACLR with an intact lateral meniscus as the comparator, while two directly compared LMPRT repair with untreated LMPRTs. Meta-analysis demonstrated no statistically significant between-group differences in postoperative International Knee Documentation Committee (IKDC) scores (MD, -0.43; 95% CI, -2.78 to 1.93; p=.72; I2=15%), Lysholm (MD, 0.82; 95% CI, -1.25 to 2.89; p=.44; I2=42%), Tegner (MD, -0.09; 95% CI, -0.43 to 0.24; p=.59; I2=42%), or arthrometer-measured anterior tibial translation (MD, 0.23 mm; 95% CI, -0.04 to 0.51; p=.09; I2=73%) between ACLR with LMPRT repair and isolated ACLR with an intact lateral meniscus. Knee Injury and Osteoarthritis Outcome Score (KOOS) analyses showed no statistically significant differences across five subscales (all p≥.424), with moderate-to-high heterogeneity (I2=63%-84%). The two studies comparing repair versus untreated LMPRTs reported no statistically significant differences in postoperative IKDC or Lysholm scores at 2 years (all p > 0.05). Healing according to study-specific criteria was observed in 89/110 repairs (81%). CONCLUSION: and Relevance: ACLR with concomitant LMPRT repair showed favorable short-term outcomes. Comparisons with isolated ACLR with an intact lateral meniscus do not establish benefit over no repair, and direct evidence comparing repair with no repair remains limited. Future studies should determine whether repair technique influences outcomes and whether repair improves long-term chondral and radiographic outcomes. LEVEL OF EVIDENCE: III, systematic review PROSPERO ID: CRD420261412322.