Anterolateral Ligament of the Fetal Knee: An Anatomic and Histological Study

Abstract

The findings of this study help to better understand the ALL's anatomy and histology from the fetal period to adulthood. The study presents the existence of the ALL since fetal development, emphasizes the characterization of the ALL, and brings important information to future pediatric ALL lesion studies.

The anterolateral ligament: A cadaveric study in fetuses

“…All authors have considered that the tibial attachment of the ALL is always located half way between the centre of Gerdy's tubercle and the tip of the fibular head. Helito et al () in their fetal study described a tibial attachment of the ALL slightly anterior to half the distance between the fibular head and Gerdy's tubercle (Caterine et al, ; Rezansoff et al, ) and approximately 2.5 ± 0.8 mm below the lateral articular cartilage. In contrast, in our study, the tibial attachment of the ALL was slightly posterior to half the distance between the fibular head and Gerdy's tubercle (Helito et al, ; Dodds et al, ; Runer et al, ) and it was also lower, approximately 4.1 ± 2.5 mm below the lateral articular cartilage.…”

“…Some authors have advocated that the ALL is an extracapsular ligament (Helito et al, ; Dodds et al, ; Cavaignac et al, ; Macchi et al, ; Runer et al, ), while others have identified it as a capsular thickening (Kosy and Mandalia, ; Caterine et al, ; Stijak et al, ). One study failed to identify any capsular or extracapsular ligament (Ingham et al, ).…”

“…Histological studies have demonstrated that it consists of parallel collagen bundles, mainly collagen I fibers (90%) and propioceptive nerve fibers, typical of a ligamentous structure and not a capsular joint thickening (Caterine et al, ; Macchi et al, ). Helito et al () performed a histological study of the ALL in 20 fetuses, demonstrating that it was a dense, well‐organized collagenous structure with elongated fibroblasts and a greater cell concentration than the adult ALL.…”

“…This recalls the morphology of the posterior part of the tibial collateral ligament. However, some authors have described a bifurcation of the ALL distally into two different attachments: the suprameniscal fibers that run into the lateral meniscus, and the inframeniscal fibers that extend from the meniscus to the anterolateral aspect of the tibia (Helito et al, , 2016a, ; Kosy et al, ; Parker and Smith, , Potu et al, ; Van Dyck et al, ; Corbo et al, ; Roessler et al, ).…”

“…Those authors, and others (Stijak et al, ; Macchi et al, 2016), suggested that the ALL could be developed during stress forces to the anterolateral capsule. In contrast, Helito et al () demonstrated a constant presence of the ALL in a sample of 20 fetuses.…”