Fibularis Longus
The structure indicated is the
fibularis (peroneus) longus muscle of the leg.
The
fibularis longus muscle is one of the muscles of the
lateral compartment of the leg. The leg consists of three muscular compartments: anterior, posterior and lateral. The lateral compartment consists of
two muscles:
- Fibularis (peroneus) longus
- Fibularis (peroneus) brevis
The lateral muscles are responsible for
eversion of the foot and are innervated by the
superficial fibular (peroneal) nerve, which is a branch of the
common fibular nerve. The common fibular nerve is a branch of the
sciatic nerve and divides into the
superficial fibular nerve and the
deep fibular nerve. The deep fibular nerve innervates the muscles of the anterior compartment of the leg.
The tendon of the peroneus longus passes underneath the foot to insert medially on the base of the first metatarsal and the distal medial cuneiform bone. In doing so, it runs along a groove in the cuboid bone and forms a sling for the foot, supporting the transverse arch.
Origin: superior lateral surface of fibula
Insertion: plantar surface of medial cuneiform bone and base of first metatarsal
Innervation: superficial fibular nerve
Action: eversion and plantarflexion of foot.
Learn more about the
muscles of the leg in this tutorial.
