Does anterolateral ligament rupture affect functional outcomes in patients who underwent an anterior cruciate ligament reconstruction?

Background: Studies have shown that the anterolateral ligament contributes to knee stability. This study aims to compare the results of postoperative physical examinations, knee joint stability tests, and functional assessment tests of patients with intact anterolateral (AL) ligaments and patients with ruptured anterolateral (AL) ligaments. Material and method: This study consisted of 101 patients, with at least a 12-month follow-up period, who underwent an anterior cruciate ligament reconstruction between 2010 and 2016, and whose AL ligaments were evaluated by the radiologist with the preoperative and postoperative magnetic resonance images (MRI). Of these patients, 41 had intact AL ligament (Group 1) in MRI and other 60 had ruptured AL ligament (Group 2). Groups were compared according to postoperative physical examinations, knee joint stability tests, and functional assessment tests. Results: The average Lysholm score of Group 1 was 94.9 (range: 81-100), and the score of Group 2 was 87.2 (range: 74-100). The modified Cincinnati score of Group 1 was 28.7 (24-30), while the score of Group 2 was 25.6 (21-30). The average IKDC subjective knee evaluation score of Group 1 was 91.9 (range: 83-100), and the score of Group 2 was 86.6 (range: 75-100). The average thigh atrophy value was 1.5 centimeters (cm) in Group 1 and 2.4 cm in Group 2. Thirty-three patients in Group 1 were able to jump over 85% of the distance in single-legged hop test compared to the intact side, while 16 patients in Group 2 were able to jump over this distance successfully. As a result of the analysis, it was determined that the Lysholm activity scoring results, the Modified Cincinnati scoring results, IKDC subjective knee evaluation results, two-cycle IKDC activity scale results, comparison of thigh diameters and the single-legged hop tests of two groups showed a statistically significant difference, and the results of the patients with intact AL ligaments who underwent an ACL reconstruction were found to be better (p < 0.05). No significant difference was found in other examinations and tests. Conclusion: Since the rupture of the AL ligament has negative effects on functional outcomes, we think that the reconstruction of the AL ligament in the same session with the ACL reconstruction or later will have a positive effect on functional outcomes.