Anatomical Insights into the Lateral Meniscus and Anterolateral Ligament: A Cadaveric Study.

Background/Objectives: This study aims to describe in detail the previously reported close relationship between the anterolateral ligament (ALL) and the lateral meniscus. Few previous studies identified and characterized this relation. This study further characterizes the anatomical relation between the ALL and the lateral meniscus through meticulous cadaveric dissection. Methods: A total of 31 cadaver knees were dissected. The ALL relation with the lateral meniscus was explored using a specific dissection protocol that involved removing the central pivot (cruciate ligaments) and medial structures of the knee to enhance visualization of the anterolateral complex. The zone and attachment pattern of the ALL on the lateral meniscus were recorded. Results: The ALL was found in all 31 dissected knees and in all cases has an attachment to the lateral meniscus. It was attached in zone 2b of the lateral meniscus in 97% of cases. The median anteroposterior length of attachment of the ALL on the lateral meniscus was 6 mm (25th and 75th percentiles of 5-7 mm). Almost 80% (77.4%) of ALL attachments on the lateral meniscus were full thickness or bipolar (superior and inferior margins). In the remaining knees, the ALL was fixed only in the upper part (4 knees, 12.9%) or only in the lower part (3 knees, 9.7%) of the lateral meniscus. Conclusions: The ALL has an attachment to the lateral meniscus in all studied knees, with its most prevalent site at zone 2b. The most frequent types of ALL attachment on the lateral meniscus were full thickness or bipolar. These anatomic insights support targeted anterolateral augmentation and meniscal preservation to optimize clinical results.