Summary Flexor Hallucis Longus Origin Inferior 2/3 of posterior surface of fibula, lower part of interosseous membrane Insertion Plantar surface of base of distal phalanx of great toe Action Flexes great toe, helps to supinate ankle, and is a very weak plantar flexor of ankle Innervation Tibial nerve (S2, S3) Arterial Supply Muscular branch of peroneal and posterior tibial artery