The Flexor hallucis longus is one of the deep muscles of the lower limb. Flexor hallucis longus is present in the deep posterior compartment of the leg along with other deep muscles of the leg.
Muscles of deep posterior compartment of leg
The muscles of the posterior compartment of the leg include:
- flexor hallucis longus
- flexor digitorum longus
- tibialis posterior
- popliteus
Strongest muscle of deep posterior compartment of leg
FHL is the largest and most powerful of these deep muscles.
Origin of flexor hallucis longus muscle
Flexor hallucis longus originates from the upper 1/3rd of fibula bone posteriorly.
Insertion of flexor hallucis longus muscle
It gets inserted into the distal phalanx of the big toe (hallux, hence the name).
Blood supply of flexor hallucis longus muscle
Arterial supply of flexor hallucis longus muscle is from the peroneal artery, which is the branch of posterior tibial artery.
Nerve supply of flexor hallucis longus muscle
Its neurological supply is from S1 and S2 nerve roots through tibial nerve.
Actions of flexor hallucis longus muscle
The actions of flexor hallucis longus muscle include:
- flexion of all big toe joints
- plantar flextion at the ankle joint
Antagonist of flexor hallucis longus muscle
Antagonist of flexor hallucis longus muscle is extensor hallucis longus.
FHL Table
| Origin | posterior aspect of upper 1/3rd of fibula |
| Insertion | base of distal phalanx of hallux(big toe) |
| Artery | Peroneal artery (peroneal branch of the posterior tibial artery |
| Nerve | tibial nerve, S1 & S2 nerve roots |
| Actions | flexes all joints of the big toe, plantar flexion of the ankle joint |
| Antagonist | Extensor hallucis longus muscle |