Anatomy of the leg

Introduction to Leg Compartments00:00:03

The leg is the region between the knee and ankle, organized into three fascial compartments: anterior, lateral, and posterior, defined by the interosseous membrane and intramuscular septa.

Anterior Compartment00:00:28

Also known as the extensor or dorsiflexor compartment, it contains four muscles: tibialis anterior, extensor digitorum longus, extensor hallucis longus, and fibularis tertius. These are innervated by the deep fibular nerve and supplied by the anterior tibial artery.

Lateral Compartment00:07:24

This compartment consists of the fibularis longus and brevis muscles, which are responsible for foot eversion and weak plantar flexion. It is innervated by the superficial fibular nerve.

Posterior Compartment00:10:37

The largest compartment, divided into superficial (gastrocnemius, soleus, plantaris) and deep (popliteus, flexor digitorum longus, flexor hallucis longus, tibialis posterior) subcompartments. It is innervated by the tibial nerve and supplied by the posterior tibial and fibular arteries.

Tarsal Tunnel and Clinical Landmarks00:17:47

The structures entering the foot behind the medial malleolus pass through the tarsal tunnel. The mnemonic 'Tom, Dick, and Nervous Harry' helps identify the arrangement of tendons and neurovascular structures from anterior to posterior.

Summary and Recap00:20:51

A final review of the three compartments, their muscular composition, and key anatomical functions including dorsiflexion, plantar flexion, inversion, and eversion.