Arteries of the leg

Anterior tibial artery

The anterior tibial artery (a. tibialis anterior) is the sole major vessel of the anterior fascial compartment of the leg.

It originates from the popliteal artery at the level of the lower border of the popliteal muscle. Immediately after its origin, it pierces the interosseous membrane of the leg (membrana interossea cruris) in its upper part and emerges onto the anterior surface. In the leg, the artery descends alongside the deep fibular nerve (n. fibularis profundus) between the anterior group of muscles (initially between the tibialis anterior and extensor digitorum longus, and then between the tibialis anterior and extensor hallucis longus).

After passing under the inferior extensor retinaculum at the ankle joint level, it continues as the dorsalis pedis artery (a. dorsalis pedis). Along its course, it gives off recurrent branches to the knee joint, muscular branches, and anterior malleolar arteries.

Clinical significance: The anterior compartment of the leg is a closed osteofascial space. Trauma or overuse can cause edema here, leading to compartment syndrome. Elevated pressure compresses the vessel and nerve. An early sign of ischemia is pain and sensory loss in the first web space of the foot, whereas the loss of pedal pulses occurs at later stages when the muscles are irreversibly damaged.

Posterior tibial artery

The posterior tibial artery (a. tibialis posterior) is the larger terminal branch of the popliteal artery, serving as the main source of blood supply to the sole.

It descends within the cruropopliteal canal (Gruber's canal) alongside the tibial nerve (n. tibialis). In the lower third of the leg, the vessel emerges from beneath the medial border of the soleus muscle and lies superficially, beneath the deep fascia. Further down, the artery curves behind the medial malleolus, passing through the malleolar canal beneath the flexor retinaculum. In the sole, it divides into its terminal branches: the medial and lateral plantar arteries.

In addition to robust muscular branches to the posterior compartment, the artery gives off the nutrient artery of the tibia (a. nutricia tibiae), which is the largest nutrient artery in the human skeleton.

Pulse point: the pulse of the posterior tibial artery is checked posterior to the medial malleolus, midway between its edge and the calcaneal tendon. This is a crucial landmark in the diagnosis of diabetic angiopathy.

Fibular artery

The fibular artery (a. fibularis or peronea) is the largest branch of the posterior tibial artery (branching off in the upper third of the leg). It is not an independent branch of the popliteal artery.

The vessel courses laterally and inferiorly into the inferior musculoperoneal canal (canalis musculoperoneus inferior) between the fibula and the flexor hallucis longus muscle.

Its branches supply the posterior and lateral muscles of the leg. Clinically, the perforating branch (r. perforans) is extremely important: it pierces the interosseous membrane in the lower third and emerges onto the dorsum of the foot. If the dorsalis pedis artery is poorly developed, the perforating branch of the fibular artery takes over its function.

The fibular artery is frequently used by surgeons as a vascular pedicle in fibular autotransplantation.

Blood supply to the leg compartments and anastomoses

The leg is divided into three fascial compartments, each with its own blood supply characteristics:

The lateral compartment is unique in that it lacks its own dedicated major artery passing through it; it is supplied by muscular and perforating branches of the fibular artery.

The arteries of the leg form a rich network of anastomoses. Around the knee joint, recurrent branches of the anterior tibial artery anastomose with genicular arteries. In the lower third of the leg, the fibular and tibial arteries exchange branches, forming the malleolar and calcaneal networks (rete malleolare, rete calcaneum). Consequently, if one of the major vessels is occluded, blood flow to the foot may be preserved.

Class and exam questions

What else to study on this topic

• Topography and walls of the cruropopliteal canal (Gruber's canal)
• Malleolar canal: boundaries and arrangement of structures
• Arterial networks of the knee, ankle, and heel
• Anatomical basis of anterior compartment syndrome
• Characteristics of lower limb collateral circulation

Other topics in the "Angiology" section

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.