nilkkaniveltä

Nilkkanivel (ankle joint) is a hinge-type synovial joint that connects the lower leg to the foot. It comprises two adjacent joints: the talocrural joint, formed by the distal ends of the tibia and fibula articulating with the trochlea of the talus, and the subtalar joint, between the talus and calcaneus. The talocrural joint primarily permits dorsiflexion and plantarflexion, while the subtalar joint enables inversion and eversion, aiding balance and adaptation to uneven surfaces. The joint is stabilized by a complex ligamentous system and a fibrous capsule.

Ligaments and stability: Medially, the deltoid ligament provides strong support; laterally, the anterior talofibular, calcaneofibular, and posterior talofibular ligaments form the lateral ligament complex. The distal tibiofibular syndesmosis, reinforced by anterior and posterior tibiofibular ligaments, stabilizes the connection between the tibia and fibula. Blood supply comes from the tibial and peroneal arteries, and innervation is primarily through branches of the tibial nerve.

Function and clinical relevance: The ankle bears body weight during standing and locomotion and enables walking, running, and jumping. Common injuries include lateral ankle sprains (often affecting the ATFL), malleolar fractures, and, less frequently, syndesmotic injuries. Chronic instability and osteoarthritis may develop after recurrent injuries.

Diagnosis and treatment: Evaluation combines physical examination and imaging (X-ray, MRI as needed). Management depends on injury severity. Minor sprains are treated with rest, ice, compression, elevation, and gradual rehabilitation; more severe injuries may require immobilization or surgical repair or fixation. Recovery typically involves rehabilitation to restore range of motion and strength.