Extensor hallucis brevis muscle

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Extensor hallucis brevis is a small muscle on the top of the foot that helps lift (extend) the big toe. It is considered the medial part of the extensor digitorum brevis, and some anatomists debate whether they are separate muscles. It starts from the calcaneus (heel bone) and inserts on the proximal phalanx of the big toe. It is supplied by the deep fibular (deep peroneal) nerve, the same nerve that innervates extensor digitorum brevis. Its main action is to extend the big toe, with flexor hallucis brevis as its opposing muscle.