Prevalence of Medial Meniscus Injury After Delayed ACL Reconstruction

Background: The menisci serve as secondary stabilizers in the knee, and anterior cruciate ligament (ACL) tears have been associated with meniscal tears. Previous studies have indicated that a delay ≥12 months is associated with development of new meniscal pathology in an ACL-deficient knee. Some studies have indicated that the time period might be shorter in the pediatric and adolescent population, and other predictive factors remain poorly defined. Purpose: To examine the association between time, patient-related factors, and the extent and location of meniscal pathology for patients of all ages with ACL reconstruction. Study Design: Cohort study (prognosis); Level of evidence, 3. Methods: This multicenter retrospective cohort analysis of 2033 patients with ACL reconstruction, aged 9 to 73 years, included those who underwent ACL reconstruction between 2013 and 2023. Multivariable logistic regression analysis was used to model meniscal tear patterns based on age, sex, activity level, and surgery interval. Results: Delayed ACL reconstruction (>120 days postinjury) was associated with a significantly higher prevalence of medial meniscus tears ( P < .001). Multivariable analyses revealed that delayed surgery increased the odds of medial meniscus tears by 80% (adjusted odds ratio [aOR], 1.80; 95% CI, 1.47-2.21; P < .001) and both medial and lateral tears by 47% (aOR, 1.47; 95% CI, 1.10-1.97; P < .009). Furthermore, male sex was associated with an elevated prevalence for meniscal tears at all time points compared to female sex, demonstrating 43% higher odds of medial meniscus tears (aOR, 1.43; 95% CI, 1.18-1.74; P < .001), 61% higher odds of lateral meniscus tears (aOR, 1.61; 95% CI, 1.34-1.93; P < .001), and 50% higher odds of both medial and lateral meniscus tears (aOR, 1.50; 95% CI, 1.13-1.98; P < .005). Conclusion: These results highlight the importance of timely surgical management to mitigate progressive intra-articular damage, with special consideration for male athletes and patients at high risk for delayed intervention.