The ankle joint is made up of three bones: the tibia, the fibula and the talus. These bones are held together by a series of tendons and ligaments. Tendons attach muscle to bone. The tendons attach to various muscles which provide mobility. Ligaments attach bone to bone.
An ankle sprain is a insult to the integrity of the ligament. The most commonly injured ligament is the anterior talo-fibular ligament. This ligament connects the front part of the fibula to the talus bone on outside part of the ankle joint.
Abnormal loading onto the muscles, tendons, and ligaments of the ankle are caused most commonly by a twisting force such as when the ankle “rolls over.”