rocker bottom foot
isolated congenital vertical talus (CVT) is a rare pedal deformity recognizable at birth by a dislocation of the talonavicular joint, resulting in a characteristic radiographic near-vertical orientation of the talus
en-US/ˈɹɑkɚ ˈbɑdəm ˈfʊt/
en-GB/ˈɹɒkə ˈbɒtəm ˈfʊt/