Flexor Digitorum Longus: The flexor digitorum longus muscle is positioned on the tibial side of the leg. At its origin, it is tiny and pointed, although it progressively expands in size as it descends.
Origin: Medial and posterior surface of the tibia, distal to the popliteal line.
Insertion: The flexor digitorum longus divides into four slips after crossing within the medial intermuscular septum of the plantar surface of the foot; On the plantar surface at the base of the distal phalanges of the second, third, fourth and fifth toes.
Function: Flexes toes 2 – 5; also helps in plantar flexion of ankle joint. When the ankle is plantarflexed, the muscle is unable to perform its flexion action of the toes
Nerve Supply: Tibial nerve (S2, S3)