The talus is trapezoidal in shape, with the greater width anteriorly. As the joint moves into plantar flexion, the talus becomes narrower, resulting in a decrease in stability. During normal walking, the ankle joint bears 3-5 times the body weight. This factor increases severalfold during running and jumping activities. As weight is applied on heel strike, the fibula descends to increase stability of the ankle joint.
Associated fractures are the rule rather than the exception.
Ligamentous disruption varies according to the type of dislocation. Neurovascular injury is the principal concern, as with any dislocation. Vascular compromise may result in avascular necrosis of the talus if not promptly reduced. Tented skin may be subject to ischemic necrosis. This presumably is related to their increased risk overall for traumatic injury.