[TA] a wide band passing from the medial malleolus to the medial and upper border of the calcaneus and to the plantar surface as far as the navicular bone; it holds in place the tendons of the tibialis posterior, flexor digitorum longus, and flexor hallucis longus. SYN: retinaculum musculorum flexorum membri inferioris [TA], laciniate ligament, ligamentum laciniatum, retinaculum of flexor muscles.