Outcomes following anterior cruciate ligament injury with concomitant damage to the medial collateral ligament.

Abstract

Introduction: Anterior cruciate ligament (ACL) rupture with concomitant damage to the medial collateral ligament (MCL) is frequently seen following knee trauma. Non-surgical treatment of the MCL lesion generally results in good internal healing, but surgery may be necessary depending on the location of the lesion, the severity, and the laxity.

Objectives: To determine outcomes following ACL reconstruction surgery when there is concomitant damage to the MCL compared to isolated ACL lesions, as assessed through a prospective, multi-center cohort study in France.

Materials and methods: In this prospective, multi-center cohort study, patients who had a primary ACL lesion with or without concomitant damage to the MCL, and who had undergone ACL reconstruction surgery were included. Complications related to the surgery were evaluated prospectively (ACL re-rupture, contralateral rupture, reoperation), and functional scores were obtained until the last follow-up (subjective IKDC, Tegner, ACL-RSI, and SKV).

Results: A total of 722 patients were included in the study: 314 (43.5%) with an isolated ACL lesion and 408 (56.5%) with a combined ACL + MCL lesion. The ACL + MCL group had a significantly higher reoperation rate than the ACL group (7.4% versus 3.2%, p = 0.015). The ACL + MCL group also had mean IKDC and SKV scores at the last follow-up that were significantly poorer than the ACL group (p < 0.0001). High-grade MCL lesions (grade II or III) were identified in 18.2% of cases, and this was found to be predictive of poorer functional scores at the last follow-up. The mean IKDC score was significantly better when non-surgical MCL treatment was possible (p = 0.005). When MCL surgery was indicated, all of the functional scores were significantly better for ligament reinsertion surgery compared to ligament reconstruction.

Conclusion: For combined ACL + MCL lesions, the outcomes are poorer, with a higher reoperation rate and lower functional scores. For high-grade MCL lesions, the functional recovery is poorer, particularly when there are chronic lesions that require multi-ligament reconstruction.

Level of evidence: II; prospective cohort study.