The tibiocalcaneal ligament is the most posterior component of the superficial deltoid ligament, running from the medial malleolus to the medial surface of the sustentaculum tali. It is the deepest of the superficial deltoid bands and the strongest, providing the primary medial ankle support against eversion and subtalar valgus during the stance phase of walking.
The primary medial ankle stabiliser against eversion, providing hindfoot valgus restraint and preventing excessive subtalar eversion during walking and running. It works synergistically with the deep tibiotalar ligament to stabilise the medial mortise.
The tibiocalcaneal ligament is assessed clinically by palpating the sustentaculum tali region posterior to the navicular. In chronic medial ankle instability, this ligament's attenuation allows progressive hindfoot valgus deformity. In adult-acquired flatfoot, the tibiocalcaneal and tibiospring ligaments are reconstructed as part of the deltoid ligament repair when addressing the medial ankle deficiency. Repair of this ligament during calcaneal fracture surgery may be required when the sustentaculum is disrupted.
Attenuation of the tibiocalcaneal and other deltoid components from chronic eversion sprains or inflammatory arthritis produces medial ankle laxity with hindfoot valgus gait pattern, managed with orthotic support, physiotherapy, or deltoid ligament reconstruction for functional instability.
