TalusCalcaneus

TalusCalcaneus is a term used to describe the anatomical relationship and functional unit formed by the talus (ankle bone) and the calcaneus (heel bone) in the hindfoot. The key articulation between these bones is the subtalar joint, which enables inversion and eversion of the foot during gait. The subtalar joint comprises multiple articular facets where the inferior surface of the talus interfaces with the superior facets of the calcaneus, typically described as posterior, middle, and anterior facets. The joint is supported by a capsule and several ligaments, most notably the interosseous talocalcaneal ligament within the tarsal canal, along with surrounding cervical and lateral ligaments.

The talus transmits axial loads from the tibia to the calcaneus, while the calcaneus provides the primary weight-bearing surface for heel contact. Together, the talus and calcaneus participate in the hindfoot’s complex motion as part of the subtalar and talocalcaneonavicular region, contributing to overall foot flexibility, stability, and shock absorption. This talocalcaneal complex also interacts with adjacent joints, such as the talocalcaneonavicular and calcaneocuboid joints, to coordinate hindfoot movement during locomotion.

Clinical relevance of the talus–calcaneus unit includes conditions such as talocalcaneal coalition, a congenital fusion between these bones that can cause hindfoot rigidity and pain. Traumatic injuries, including fractures of the talus or calcaneus, can disrupt subtalar alignment and hindfoot mechanics, potentially leading to post-traumatic arthritis. Imaging modalities such as radiographs, computed tomography, and magnetic resonance imaging aid in assessment.

See also: talus, calcaneus, subtalar joint, talocalcaneal coalition, hindfoot.