The damage is basically a dislocation of the tibialis posterior tendon plus the tibialis posterior tendon runs along the internal ankle and it’s held back by like a little bit rubber band which we phone a retinaculum https://www.google.com/maps/d/edit?mid=1FpQiYaE-1vkfw-VwpPYM4zOIX5GqnGc&usp=sharing