Group 2: 150U (x 7.5 ml) Xeomin® 20U/ml Sol + 150U (x 7.5 ml) placebo RF + 100U (5ml) Xeomin® distributed between tibialis posterior, FHL (flexor hallucis longus), FCB (flexor digitorum brevis), gastrocnemius muscles or peroneus longus, based upon investigator clinical judgment.