Which one is the appropriate name? There is a lot of discussion going on as to which is the more suitable name. There are advantages for both name.
A lot of it depends on what the primary issue and whether it represents a primary concern of the posterior tibial tendon or is the main cause. https://podiatry-portal.com/adult-acquired-flatfoot-or-posterior-tibial-tendon-dysfunction-or-progressive-collapsing-foot-deformity/