[Variations in the calcaneo-fibular ligament (lig. calcaneofibulare). Application to the kinematics of the ankle].

The authors observe variations in the calcaneo-fibular ligament because this ligament controls two articulations, the talo-crural and the subtalar. This study is based on the dissection of the ankle of 20 specimens. The calcaneo-fibular ligament is reinforced by the ventral and lateral talo-calcaneus ligaments with variations. 3 types of disposition have been described. Type A: A lateral talo-calcaneal ligament reinforces the calcaneo-fibular ligament. These two ligaments are divergent on the proximal, medial, or distal part. Type B: There is an independent lateral talo-calcaneal ligament forward of the calcaneo-fibular ligament. Type C: A ventral talo-calcaneal ligament is observed, parallel to the interosseous ligament. The authors consider the consequences of variation in the lateral ligaments of the ankle for the functioning of the tibio-tarsal articulation, the subtalar articulation and the astragalo-scaphoid articulation in order to propose specific radiographic examination of the kinematics of the ankle.