Description
Purpose: Concomitant meniscal injuries are commonly observed in acute ACL injuries, with reported prevalence ranging from 44.4% to 65%. However, the incidence and location of meniscal tears have shown varying results among studies. Therefore, this study aimed to analyze the prevalence and geographic mapping of meniscal tears in acute ACL injuries.
Methods: A total of 139 patients who underwent primary ACL reconstruction within six weeks were included in this retrospective study from July 2015 to January 2023. Arthroscopic findings and surgical records were reviewed, and the posteromedial and posterolateral joint spaces were evaluated through intercondylar notch view or posteromedial or posterolateral portal to confirm menisco-capsular junctional tear. The Cooper’s classification system was used to document the location of tears, and radial and longitudinal components of meniscal tears were analyzed. Subgroup analysis was performed based on whether or not the remnant ACL fiber was attached to the femur, with Group 1 (n=90) defined as the case where ACL fibers remained partially attached and Group 2 (n=49) defined as the case where ACL fibers were completely ruptured.
Results: The prevalence of meniscal tears was 73%, with medial and lateral meniscal tears observed in 45% and 56% of cases, respectively. Radial tears were observed in 22.3%, with lateral root tear (12.9%) being the most common. Longitudinal tears were observed in 64.7%, with medial and lateral menisco-capsular junctional tears being the most common (42.4% and 40.3%). Zone A0 and A1 were the most commonly involved tear sites in the medial meniscus (39.6% and 42.4%), and Zone F0 and F1 were the most commonly involved tear sites in the lateral meniscus (36.7% and 41.7%). In subgroup analysis, medial and lateral menisco-capsular junctional tears were significantly more frequent in Group 1 compared to Group 2 (88.9% vs 25.6%, p<0.001, OR=25.3 and 62.2% and 6.1%, p<0.001, OR=7.2).
Conclusion: Menisco-capsular junctional tears are the most common type of tear in acute ACL injuries, with a higher prevalence of meniscal tears compared to previous reports. In acute ACL injuries, Zone A0-A1 and Zone F0-F1 should be checked through intercondylar notch view or posteromedial or posterolateral portal.
