IS PERCUTANEOUS MEDIAL COLLATERAL LIGAMENT (MCL) RELAXATION DURING ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION A SAFE OPTION FOR GAINING ACCESS TO THE MEDIAL KNEE COMPARTMENT IN CHILDREN?

INTRODUCTION: With participation in youth sports anterior cruciate ligament (ACL) injuries are a common occurrence. Nearly 70% of ACL tears in children and adolescents have an associated meniscus tear. Percutaneous medial collateral ligament (MCL) relaxation has been described as utilitarian in accessing the medial meniscus for diagnostic assessment and treatment in the adult population to increase medial compartment working space in arthroscopic surgery. The technique has not been evaluated in the pediatric population. The purpose of this study was to compare the outcomes of children and adolescents that underwent anterior cruciate ligament reconstruction (ACLR) with and without percutaneous relaxation of the medial collateral ligament (MCL) for meniscal tear management. METHODS: A retrospective review was performed of patients aged 8 to 19 years old that had undergone knee arthroscopy for an (ACLR) with meniscus pathology. Those that underwent MCL relaxation were grouped together and compared to a matched cohort that did not have MCL relaxation performed. Preoperative, operative and postoperative data was analyzed. The primary measurement was obtained using a validated patient reported outcome score (Pedi-IKDC), secondary outcome measures were defined as superficial or deep infection, saphenous nerve dysesthesias, ACL graft failure and return to the operating room. Statistical analysis of the two cohorts was performed. RESULTS: Fifty-four patients were included in the study (27 in each group) with average age 15 years (range 10-19). Average follow-up for the MCL relaxation group was 22.4 months versus 58 months for the non-MCL relaxation group. The average Pedi-IKDC score was 93.3 for the MCL relaxation group and 91.4 for the non-MCL relaxation group (p=0.34). There was no difference in patient demographics, return to the operating room (p=0.49), saphenous nerve dysesthesia (p=0.49), superficial or deep infection (p=0.32). CONCLUSION: ACL reconstruction in children and adolescents with MCL relaxation for the management of medial meniscal tears appears to be a safe option. Equivocal patient reported outcome scores as compared to the control group were found with no increase in post-operative complications. In children with ACL tears, appropriate diagnosis and management of medial meniscal pathology is important to maintain secondary restraint to anterior tibial translation and prevent premature graft failure. Pediatric knees can have tight medial compartments, making access difficult, potentially leading to poor visualization and iatrogenic chondral damage. Percutaneous medial collateral ligament (MCL) relaxation has been described in the adult population to increase medial compartment working space without long term sequela. We report similar findings in an all pediatric cohort.