Talocruralleddet

The talocrural joint, also known as the ankle joint, is a hinge-type synovial joint that connects the distal ends of the tibia and fibula with the upper part of the talus. The distal tibia and fibula form the ankle mortise, a shallow bony socket that houses the trochlea of the talus. The articular surfaces include the tibial plafond and the medial and lateral malleolar contributions, which together constrain the talus within the mortise.

Movement at the talocrural joint is primarily dorsiflexion and plantarflexion, allowing the foot to move up and down relative to the leg. The joint’s bony configuration and strong ligamentous support limit excessive medial-lateral movement and rotation, though the tibia-tibiofibular articulation and the mortise permit a small amount of axial rotation when the ankle is flexed.

Stability of the talocrural joint is provided by several ligaments. The lateral ligament complex, consisting of the anterior talofibular, calcaneofibular, and posterior talofibular ligaments, resists inversion injuries. Medially, the deltoid ligament provides strong restraint to eversion. The distal tibiofibular syndesmosis, reinforced by the anterior inferior and posterior inferior tibiofibular ligaments and the interosseous tibiofibular ligament, stabilizes the relationship between the tibia and fibula, especially during weight-bearing. The joint is surrounded by a fibrous capsule and a synovial lining, with vascular and neural supply typical of synovial joints.

Clinically, the talocrural joint is commonly injured through ankle sprains, particularly lateral ligament injuries, or through syndesmotic (high ankle) injuries. Osteochondral lesions and degenerative changes can occur with recurrent or severe trauma.