Leg Muscles: Origin, Insertion, Action & Nerve Supply

Leg Muscles: Leg muscles are divided into three compartment-

Anterior compartments of the leg
Lateral compartment of the leg
Posterior compartment of the leg

Anterior compartment of the leg

Four muscles in the anterior compartment of the leg-

• Tibialis anterior
• Extensor digitorum longus
• Extensor hallucis longus
• Fibularis tertius

Anterior compartment of the leg muscles acts to dorsiflex and invert the foot at the ankle joint.  The extensor digitorum longus and extensor hallucis longus muscles also extend the toes. The anterior compartment of the leg muscles are innervated by the deep fibular nerve (L4-L5), and blood is supplied via the anterior tibial artery.

Lateral compartment of the leg

Two muscles in the Lateral compartment of the leg-

•  Fibularis longus
•  Fibularis brevis

They are also known as peroneal longus and brevis. The function of the Anterior compartment muscles is eversion. They are innervated by the superficial fibular nerve.

Posterior compartment of the leg

Seven muscles are in the posterior compartment of the leg, organized into  – superficial and deep layers. The two layers are distributed by a band of the fascia. The posterior compartment of the leg is the largest of the three compartments, the muscles in this area act as plantarflex and invert the foot. They are innervated by the tibial nerve.

Superficial Muscles-

• Gastrocnemius
• Plantaris
• Soleus

Deep Muscles-

• Popliteus
• Tibialis Posterior
• Flexor Digitorum Longus
• Flexor Hallucis Longus