Deep Posterior Compartment of the Leg

compartimentum posterius profundum cruris

The deep posterior compartment of the leg lies deep to the transverse intermuscular septum and contains tibialis posterior, flexor digitorum longus, flexor hallucis longus, the tibial nerve, and the posterior tibial artery. It is enclosed by the tibia medially, fibula laterally, interosseous membrane anteriorly, and the transverse septum posteriorly.

Anatomical Data

Boundaries & Contents

Location	Back of the leg, deep to soleus
Boundaries	Posterior surface of the tibia (front and medial) Interosseous membrane (front) Posterior surface of the fibula (lateral) Transverse intermuscular septum (back)
Contents	Tibialis posterior Flexor digitorum longus Flexor hallucis longus Popliteus (at the top) Tibial nerve Posterior tibial artery and veins Fibular (peroneal) artery and veins

Biomechanics

Function & Actions

Holds the deep flexors that support the arch and flex the toes, with the main neurovascular bundle to the sole. It can be missed during fasciotomy because it lies under soleus.

Clinical Relevance

Clinical Notes

The deep posterior compartment is the most frequently missed compartment in lower leg fasciotomy and has the greatest consequence if undertreated, as its contents are critical for ankle and toe function. Pressure monitoring via a Stryker device placed through the transverse septum is required for accurate assessment. Chronic exertional deep posterior compartment syndrome is the most common cause of medial tibial shin pain in runners after excluding tibial stress injury.

Pathology

Common Injuries & Conditions

Deep Posterior Compartment Syndrome

Pressure elevation causing tibialis posterior, FDL, and FHL ischaemia and tibial nerve compression, producing foot inversion weakness, toe flexor loss, and plantar anaesthesia.

Chronic Exertional Deep Posterior Compartment Syndrome

Exercise-induced reversible pressure elevation producing medial shin pain that begins after a consistent distance and resolves within 30 minutes of rest, diagnosed by post-exercise intracompartmental pressure.

Explore

More in Lower Leg

Browse all of Lower Leg →