An inner-side pillar supporter according to the present invention includes a plate-shaped pillar including: a fixed portion coming into contact with an inner side of an ankle joint at the malleolus medialis from an inner side of a calcaneus, and an inversion preventing portion formed integrally with the fixed portion to extend over the malleolus medialis； and a fixing member press fixing the fixed portion of the pillar onto the inner side of the ankle joint at the malleolus medialis from the inner side of the calcaneus.
