Poster 249: Low Failure Rate in a Young Cohort of Patients Undergoing Anterior Cruciate Ligament Reconstruction with Quadriceps Tendon is Independent of Graft Fixation Methods

OBJECTIVES: To determine failure and clinical outcomes of anterior cruciate ligament reconstruction (ACLR) with quadriceps tendon in a young cohort of patients, and, secondarily, determine if method of femoral and tibial fixation of the graft affects these outcomes. METHODS: All patients aged 10-30 years old who underwent primary ACLR with quadriceps tendon autograft from 2010 to 2021 were retrospectively analyzed. Patients with double-bundle ACLR, posterolateral corner augmentation, and revision ACLR were excluded. Patient demographics, surgical details, ACLR failure, and pre- and post-operative International Knee Documentation Committee (IKDC) scores were recorded. The primary outcome was ACLR failure and secondary outcome was post- operative IKDC score. Patients were further categorized into three groups based on femoral and tibial fixation: suspensory/suspensory (Group 1), suspensory/aperture (Group 2), and aperture/aperture (Group 3). Suspensory fixation included fixed loop, adjustable loop, and screw and washer fixation, whereas aperture fixation included use of interference screw. Chi Squared analyses were used to analyze categorical outcomes, and ANOVA and Kruskal-Wallis tests were used to analyze continuous outcomes. Significance was set at p < 0.05. RESULTS: A total of 350 patients were included for analysis. The average age of the cohort was 19.4 (+/- 4.3) years old, and the average follow-up length was 12.6 (+/- 7.0) months. BMI, sex, and laterality of procedure were statistically similar. ACLR failure rate in the cohort was 4.9% overall, and mean post- operative IKDC score was almost two times higher than mean pre-operative IKDC score (76.2 vs 38.8, respectively). When dividing the cohort based on fixation type, 122 patients had femoral and tibial suspensory fixation, 191 patients had femoral suspensory and tibial aperture fixation, and 37 patients had femoral and tibial aperture fixation. ACLR failure rate was statistically similar across groups (6.6% (1), 4.7% (2), 0% (3); p > 0.05). Further, post-operative IKDC scores did not differ significantly across groups (74.2 (1), 77.1 (2), 79.2 (3); p > 0.05). CONCLUSIONS: Results of this study suggest that quadriceps tendon autograft is a viable option for ACL reconstruction in young patients, as demonstrated by a low failure rate and marked increase in IKDC score post-operatively. The follow-up interval in this study was short, however, and slightly increased failure rates may be observed over time. Femoral and tibial fixation methods in this study did not influence failure rate or IKDC scores, suggesting they may not play a role in post-operative success following quadriceps tendon ACLR. Surgeons may utilize the information in this study during pre- operative planning and discussion of graft options with their patients.