Description of the lateral fibulotalocalcaneal ligament in fetal specimens and its potential clinical implications

The increase in ankle sprains in children is a reflection of the greater inclusion of this population in sports. This places the calcaneofibular (CFL) and the anterior talofibular (ATFL) ligaments in focus for study. In adults, the presence of arcuate fibers extending between these two ligaments suggests the existence of a new anatomical and functional complex called the lateral fibulotalocalcaneal ligament of the ankle (LFTCL), which can be associated with the persistence of instability of the talocrural joint in ankle sprains. This study aimed to verify the presence of arciform fibers between the CFL and ATFL in human fetuses and to study the topography of the lateral ankle region.

Forty matched fetal ankles aged between 28 and 38 weeks, fixed in 4% formalin, were macroscopically, chemically and mesoscopically dissected and analyzed in stereoscope.

The ATFL was characterized as a capsular ligament consisting of two fascicles (proximal and distal). The CFL was characterized as an extracapsular ligament. The LFTCL complex was verified in all specimens, characterized by the arcuate fibers between the ATFL and the CFL.

Such results suggest that this functional unit is congenital and that it should be taken into consideration in the treatment of persistent ankle instabilities in the pediatric population.