Epidemiology and Characteristics of Meniscal Tears in Patients With Combined ACL and Medial Collateral Ligament Injuries Versus Isolated ACL Tears: A Case-Control Study From the Francophone Arthroscopic Society

Background: The co-occurrence of anterior cruciate ligament (ACL) rupture with medial collateral ligament (MCL) rupture is a compound injury that can be associated with meniscal tears. Purpose: To report the characteristics of meniscal tears in knees with isolated ACL versus combined ACL and MCL injuries, analyzing their frequency, distribution by site, and lesion type. Study Design: Cross-sectional study; Level of evidence, 3. Method: This prospective, multicenter, case-control study, conducted across 10 hospitals in France as part of a symposium of the national French Society of Arthroscopy, compared patients undergoing ACL reconstruction with and without MCL injury. The 2 groups were matched by sex, age (±3 years), and body mass index (±3) to minimize imbalances between groups. All operations were performed by senior surgeons, who systematically explored for ramp, root, and other types of meniscal lesions as well as corner injuries. The primary outcome focused on meniscal injury frequency, with secondary outcomes examining lesion sites and types. A subgroup analysis was performed to compare these outcomes depending on the injury chronicity. Acute ACL injuries were those treated within 3 months of injury, and chronic lesions were those treated after this period. Results: A total of 722 patients were included, with a mean age of 30.32 ± 10.78 years. Meniscal injuries were observed more frequently in the ACL+MCL group, with 217 of 408 patients (53.2%) affected, compared with 130 of 314 patients (41.4%) in the isolated ACL group ( P = .001). Lateral meniscal lesions were significantly more common in the ACL+MCL group at 41.9% compared with 20.8% in the isolated ACL group ( P < .001). The same pattern was found independent of chronicity. Medial meniscal lesions were significantly more common in the isolated ACL group regardless of chronicity status. In terms of types of medial lesions, the ACL+MCL group primarily experienced longitudinal (45.9%) and ramp lesions (28.7%), whereas the isolated ACL group experienced mostly ramp lesion (58.3%; P < .001). No significant difference was observed in the distribution of lateral meniscal injury types. Conclusion: This study demonstrated a higher prevalence of meniscal injuries associated with ACL+MCL injuries compared with isolated ACL injuries, with lateral meniscal lesions particularly more frequent, independent of chronicity status.