Evaluation of the anterolateral ligament of the knee with high resolution ultrasound

Abstract

Objectives: To determine whether high-resolution ultrasound is an exam that contributes to the identification and assessment of the integrity of the anterolateral ligament of the knee in patients with anterior cruciate ligament injury. Methods: 41 patients, 16 to 55 years old, with primary lesion of the anterior cruciate ligament were evaluated. Demographic data were collected, and a Pivot Shift test was performed. An ultrasound examination was performed, with a high- resolution probe, on both patients' knees, initially, seeking the visualization of the anterolateral ligament in all its extension and later assessing its integrity, ending with an assessment of the lateral meniscus. Results: 100% of the evaluated cases, it was possible to visualize the anterolateral ligament through ultrasound with 46.3% of injuries, with the tibial portion being the most injured. 19 patients (46.3%) had anterolateral ligament injury on the same side as the anterior cruciate ligament injury, while in 19 cases (46.3%) no anterolateral ligament injury was observed on either side. 5 patients had a pivot shift test considered positive with 80% of associated anterolateral ligament injury. 31 patients had lateral meniscus injury by magnetic resonance imaging. Of the 31 patients, 25 were confirmed by ultrasound. Of the 11 patients without lesion of the lateral meniscus by MRI, none had an ultrasound lesion. Adding these two groups, 92.6% of results favorable to ultrasound, (p <0.001). Conclusion: The data obtained suggest that ultrasound contributes to the identification and assessment of the integrity of the knee anterolateral ligament in patients with anterior cruciate ligament injury. Level of Evidence IV.