[TA] the part of the medial or deltoid ligament that extends from the medial malleolus to the posterior process of the talus. Synonym(s): pars tibiotalaris posterior ligamenti collateralis medialis articulationis talocruralis [TA], ligamentum talotibiale posterius, posterior talotibial ligament, posterior tibiotalar ligament, posterior tibiotalar part of deltoid ligament