Ankle Joint It consists of a deep socket formed by the lower end of the tibia & fibula , into which is fitted the upper part of the body of the talus . The talus is able to move on a transverse axis in a hingelike manner. The shape of the bones & the strength of the ligaments and the surrounding tendons make this joint strong and stable Articulation It is between the lower end of the tibia & the 2 malleoli and the body of the talus. The articular surfaces are covered by hyaline cartilage. The inferior transverse tibiofibular ligament , which runs between the lateral malleolus and the posterior border of the lower end of the tibia ,deepens the socket into which the body of the talus fits.

Ankle Joint Type : it is a synovial hinge joint Capsule: It is attached to the bones near their articular margins & it encloses the joint . Ligaments The lateral ligament It is week than medial ligament and consists of 3 bands . 1- The anterior talofibular ligament it runs from the lateral malleolus to the lateral surface of the talus. 2- The calcaneofibular ligament it runs from the tip of the lateral malleolus downward and backward to the lateral surface of the calcaneum. 3- the posterior talofibular ligament it runs from the lateral malleolus to the posterior tubercle of the talus .

The medial or deltoid ligament tibiofibular talofibular The medial or deltoid ligament It is strong and is attached to the tip of the medial malleolus. Its deep fibers are attached to the nonarticular area on the medial surface of the body of the talus. Its superficial fibers are attached to the medial side of the talus , the sustentaculum tali , the plantar calcaneonavicular ligament ( spring ) and the tuberosity of the navicular bone.

Ankle Joint Synovial Membrane : It lines the capsule. Nerve Supply : Deep peroneal & tibial nerves Movements: Dorsiflexion & plantar flexion . N. B. inversion & eversion tack place at the tarsal joints . Dorsiflexion is performed by the tibialis anterior , extensor hallucis longus, extensor digitorum longus, and peroneus tertius. It is limited by the tension of the tendocalcaneus , the posterior fibers of the medial ligament and the calcaneofibular ligament. During dorsiflexion the wider anterior part of the articular surface of the talus is forced between the medial & lateral malleolus, causing them to separate slightly & tighten the ligaments of the distal tibiofibular joint. This arrangement increases the stability of the ankle joint when the foot is in the initial position for major thrusting movements in running , jumping and walk .

Plantar flexion is performed by the gastrocnemius, soleus,plantaris, peroneus longus & brevis , tibialis posterior, flexor digitorum longus and flexor hallucis longus It is limited by the tension of the opposing muscles , the anterior fibers of the medial ligament and the anterior talofibular ligament . When the ankle is fully plantar flexed, the ligaments of the distal tibiofibular joint are less taut and small amounts of rotation , abduction & adduction are possible. Important Relations anteriorly : tibialis anterior , extensor hallucis longus ,anterior tibial vessels, deep peroneal nerve, extensor digitorum longus and peroneus tertius. Posteriorly : tendo calcaneus & plantaris. Posterolaterally: peroneus longus& brevis posteromedially: tibialis posterior, flexor digitorum longus, posterior tibial vessels ,tibial nerve and flexor hallucis longus Tibiofibular Talofibular

Tarsal joints 1- Subtalar joint It is between the inferior surface of the body of the talus and the facet on the middle of the upper surface of the calcaneum. 2- Talocalcaneonavicular joint It is between the rounded head of the talus , the upper surface of the sustentaculum tali and the posterior concave surface of the navicular bone. 3- Calcaneocuboid joint It is between the anterior end of the calcaneum & the posterior surface of the cuboid . The talocalcaneonavicular & calcaneo-cuboid joints are together referred as midtarsal or transverse tarsal joints . N.B. The inversion & eversion movements take place at the 3 previous joints .