TALOCRURAL JOINT ANATOMY
Known as the ankle joint, the talocrural joint
is actually two basic articulations working in cohesive junction. Each are hinge joints
, with one formed at the end of the tibia
and one formed at the lateral malleolus of the fibula
. Each joins with the talus.
TALOCRURAL JOINT STRUCTURE
The distal joint is formed with the juncture of the medial malleolus and the tibia joining the talus. The lateral joint is formed at the juncture of the lateral malleolus and the fibula with the talus. With 4 ligament supports, the entire joint process in encapsulated within one joint capsule.
The ligaments support the ankle joints from the outside of this capsule. The tibia brings the deltoid ligament while the fibula brings the anterior talofibular ligament, the posterior talofibular ligament, and the calcaneofibular ligament.
TALOCRURAL JOINT DIAGRAM
Image: Talocrural Joint
Side to side movement of the ankle joint is restricted by the malleoli which form a capped protective covering along the upper joint surface.
TALOCRURAL JOINT FUNCTIONS
While the wrist is permitted various lateral movements as well as flexion
, the ankle joint is restricted by the denial of lateral movements and can only perform flexion
. Along the anterior of the capsule, the extensor tendons provide tension to prevent excessive plantar flexion (ankle extension) while the tendo calcaneous provides tension to prevent too much dorsiflexion.