The posterior talocalcaneal ligament: an MRI evaluation.

Purpose: A wide inter-individual variability in terms of size, orientation and insertion is observed regarding ankle ligaments. The aim of this study is to identify and describe the anatomical features of the posterior talocalcaneal ligament (PTCL) observed through the use of magnetic resonance imaging (MRI) of the ankle.

Methods: The study was retrospectively carried out on 893 ankle MRI's exams. The exams have all been performed using a 1.5-T (T) MRI. The same scanning protocols and scan planes were carried out in all the exams. The first evaluated parameter was the recognition of the PTCL. Subsequently, in all those cases where the ligament was present, its features such as insertion sites, length, and thickness were evaluated.

Results: The PTCL identification was possible in 77 exams (8.6% of the total number). Among these, we were able to identify some variants regarding insertion sites, length, and thickness. The PTCL could be further classified into four categories based on the most common characteristics observed.

Conclusions: Our study has identified different characteristics of the PTCL that allow us to further understand the characteristics of the ligament itself. In conclusion, the need for further studies focused on the biomechanical role of the PTCL in the ankle joint appears mandatory.