Awareness, Prevalence, and Magnetic Resonance Imaging Landmarks of the Aberrant Anterior Tibial Artery of the Knee.

Background: Anatomic variations of the popliteal artery are critical to recognize during preoperative planning to avoid complications. The aberrant anterior tibial artery (AATA) arises higher than the usual site of the anterior tibial artery, and it passes between the posterior tibial cortex and anterior to the popliteus muscle. Purpose: To assess AATA prevalence, magnetic resonance imaging (MRI) landmarks, intraoperative vascular injuries, and surgeon acknowledgment of the AATA presence. Study Design: Cross-sectional study; Level of evidence, 3. Methods: This study was conducted in 2 stages. During the first stage, 787 knee MRIs were reviewed to detect the AATA prevalence. In the second stage, 10 board-certified knee and sports surgeons were invited to comment on 10 knee MRIs, 5 of which showed AATA variation. This assessment was performed 3 times: (1) at baseline; (2) immediately after an instructional orientation session; (3) 2 weeks after the orientation session. Results: The prevalence of the AATA was found to be 2.03%. MRI measurements revealed that the AATA was, on average, 5.69 mm from the tibial attachment of the posterior cruciate ligament (PCL) and 9.89 mm from the posterior horn of the lateral meniscus. The anatomic variation of the AATA was most consistently visualized at the level of the tibial attachment of the PCL in 81.25% of cases. Before instructional orientation, observer surgeons failed to identify the presence or absence of the AATA on all MRI images. However, after the orientation, all observers accurately identified the AATA in both positive and negative cases immediately and after 2 weeks, achieving 100% intraobserver reproducibility. Conclusion: Popliteal artery anatomic variations may often be overlooked in preoperative planning; a detailed understanding of these variations is crucial to prevent unfortunate intraoperative complications. None of the surgeons detected the AATA on the first encounter. This highlights the importance of education in improving the detection and diagnosis of the AATA.