A previously unknown variant of the calcaneofibular ligament.

The lateral ankle joint is composed of 3 ligaments: the anterior talofibular ligament (ATFL), the posterior talofibular ligament (PTFL) and the calcaneofibular ligament (CFL). The ATFL and CFL demonstrate morphological variation, especially regarding their shape and number of bands. During standard anatomical dissection, an unusual type of triple CFL was observed: the CFL was composed of 2 bands originating on the lateral malleolus, and the presence of a lateral talocalcaneal ligament (LTC) originating on the talus bone. The insertion point of each band was located on the calcaneal bone. An understanding of these anatomical patterns allows a clearer view of ankle joint biomechanics, and improved planning and performance of surgical treatment.