Outcomes Following ACL and Grade III MCL Injuries
Authors: Westermann Robert W. , Spindler Kurt P. , Hettrich Carolyn M. , Wolf Brian R. 
Published: March 2017

Objectives: Complete disruptions of the medial collateral ligament (MCL) are rare, but do occur with anterior cruciate ligament (ACL) tears. Complete ACL/MCL injuries may be managed with ACL reconstruction and either conservative or operative treatment of the MCL. MCL tear location has also been associated with outcome. We hypothesized that outcomes would be best with acute surgery and worse with proximal MCL tears.We also hypothesized that operative management of MCL injuries would not influence outcome. Methods: Patients enrolled in a multicenter prospective longitudinal cohort who underwent unilateral primary ACL reconstruction between 2002-2008 and who had 2-year follow-up were evaluated. Patients with concomitant grade III MCL injuries treated either operatively or non-operatively were identified. Concurrent injuries (to meniscus or articular cartilage) and subsequent surgeries were documented. Comparisons of surgical chronicity (before and after 30 days from injury) and MCL tear location (femoral or tibial) were performed. Patient reported outcomes (KOOS, IKDC and Marx activity scores) were measured at the time of ACL reconstruction and at 2-year follow-up. Results: Initially, 3028 patients were identified to have undergone primary ACL reconstruction in the cohort during the identified time frame, with 2586 patients completing 2-year follow-up (85%). Complete MCL tears were documented in 1.1% (27/2586) of the cohort: 16 operatively managed patients and 11 conservatively treated MCLs during ACL reconstruction. Concurrent articular pathology was similar between groups. Clinically important differences were seen in baseline KOOS (all subscales) and IKDC scores, with lower scores seen in patients who underwent operative MCL treatment. Reoperation for arthrofibrosis was higher after operative repair of the MCL (19%) versus nonoperative treatment (9%). At 2 years the non-operative MCL cohort maintained significantly better KOOS Sports Rec (88.2 versus 74.4), KOOS QOL (81.3 versus 68.4), and IKDC (87.6 versus 76.0) scores compared to the MCL surgery group. Marx activity scores were equal between groups at the time of study enrollment, however patients who underwent operative MCL management had lower activity scores at 2 years (6.5 versus 10.7). Tibial-sided MCL injuries were associated with worse baseline outcomes compared with femoral-sided MCL injuries in terms of KOOS ADL, Sports Rec, and QOL subscales, but these differences were resolved by 2 years. Surgical chronicity did not influence 2-year outcome. Conclusion: Complete and combined ACL/MCL injuries are rare. Both operative and nonoperative management of MCL tears in our cohort demonstrated clinical improvements between study enrollment and 2-year follow-up. MCL surgery during ACL reconstruction was associated with more frequent stiffness, worse patient-reported outcomes and lower activity at 2 years. There may be a subset of patients with severe combined ACL and medial knee injuries that may benefit from operative management, however, that patient population has yet to be defined.