Poster 308: Clinical Outcomes After Multi-ligamentous Knee Injuries in Patients Over 40-Years-Old at Average 4-Years Follow-Up

OBJECTIVES: Multi-ligamentous knee injuries (MLKIs) are typically caused by high-energy mechanisms that warrant complex clinical decision-making and operative management to achieve optimal outcomes for patients. There is limited literature regarding these rare presentations, with even less information examining the clinical outcomes with respect to the age at which the injury was sustained. The purpose of this study is to investigate clinical outcomes following surgical treatment of MLKIs in patients who were at least 40-years-old at the time of their injury. METHODS: The study design was a multi-center retrospective cohort study. Forty-four patients who underwent surgical repair for MLKI from May 2013 to August 2021 and were at least 40-years-old at the time of their injury were identified from two separate institutions. Patients-reported outcomes assessed included International Knee Documentation Committee Subjective Knee (IKDC) Subjective Knee Form, the Lysholm Knee Score, the Tegner Activity Scale (TAS), return-to-sport and return-to-work surveys, and Visual Analogue Scale (VAS) for pain and satisfaction. A multiple regression model was used to quantify the impact of various factors related to the initial injury, including age, sex, BMI, time of follow-up, history of dislocation with injury, and mechanism of injury on the assessed outcome measures. RESULTS: The mean age of the cohort was 48.1 ± 7.0 years old. The mean overall follow-up was 60.8 months ± 36.3 (range 12-167)]. This cohort reported the following: mean IKDC of 63.4 ± 23.5, mean Lysholm score of 72.6 ± 23.6, and mean Tegner scores of 6.3 ± 2.2 before injury and 4.0 ± 2.0 at the time surveyed. These scores align similarly to the literature, indicating mediocre daily functional status. There were 18 patients that reported engagement in sports, with only 5 returning at a mean of 55.5 (± 26.2) weeks. The multiple linear regression model found dislocation to have a coefficient of -22.17 in relation to IKDC (p = 0.009), indicating that prior dislocation would predict a significant functional detriment as measured by the IKDC. A similar regression model with the Lysholm score as the outcome variable found dislocation to have a coefficient of -19.18 (p=.053), approaching significance. None of the other included variables were found to be significantly predicative of poorer outcome measures (p > 0.05), including age. CONCLUSIONS: These results demonstrate that age may not be a significant factor to consider with respect to operative management in patients over 40 years old. Instead, dislocation status was found to be a much more significant predictor of clinical outcomes following operative management of MLKIs. Further research should be directed toward understanding which predisposing factors affect the long-term outcomes of MLKI injuries, given the often random nature of their presentation.