What is the primary source of vascularization for the lateral foot?

Vascularization of the Lateral Foot

Primary Arterial Supply

The lateral foot is primarily vascularized by the peroneal artery (fibular artery) through its terminal branches, specifically the lateral calcaneal artery and anterior perforating branch, which supply approximately 45% of the lateral hindfoot structures. 1

Anatomical Distribution

Peroneal Artery Terminal Branches

The peroneal artery provides the dominant blood supply to the lateral foot through several key branches:

• Lateral calcaneal artery (LCA): Branches from the peroneal artery (or occasionally from the posterior tibial artery in 15% of cases) and supplies the lateral aspect of the calcaneus and lateral heel soft tissues 1, 2

• Anterior perforating branch: Emerges at a mean distance of 69.37 mm proximal to the ankle joint, with a mean diameter of 2.35 mm, and penetrates anteriorly to supply the lateral ankle and dorsolateral foot 3

• Posterior peroneal artery: Continues distally along the lateral calcaneus 3

Vascular Arcade Formation

A critical vascular arcade exists on the lateral foot formed by anastomoses between:

• Lateral calcaneal artery (from peroneal artery)
• Lateral tarsal artery (from dorsalis pedis artery)
• Lateral malleolar artery (from anterior tibial artery) 2

This arcade provides collateral circulation and defines safe surgical corridors for lateral approaches 2.

Anatomical Variations and Clinical Significance

Dominant Peroneal Artery (Arteria Peronea Magna)

• Occurs in approximately 5-5.6% of the population 3
• In these cases, the peroneal artery is responsible for entire foot vascularization through enlarged terminal branches 3
• Mean diameter of dominant peroneal arteries is 3.78 mm (versus 2.35 mm for standard anterior perforating branches) 3

Classification of Terminal Distribution Patterns

Six distinct anatomical patterns have been identified 3:

• Type 1 (40.7%): Simple bifurcation into anterior perforating and posterior peroneal branches
• Type 2 (14.8%): Proximal anterior perforating branch with distal bifurcation
• Type 3A (18.5%): Terminal trifurcation including anastomotic branch
• Type 3B (5.6%): Trifurcation with anastomotic branch connecting to posterior tibial artery
• Type 3C (13%): Proximal anterior perforating branch with distal trifurcation
• Type 3D (3.7%): Multiple proximal branches with distal trifurcation

Proximity to Fibula

The peroneal artery maintains extremely close proximity to the fibula throughout its course 3:

• At 5 cm proximal to ankle: 0.83 mm from fibula
• At 10 cm proximal to ankle: 1.24 mm from fibula
• At 15 cm proximal to ankle: 1.63 mm from fibula

Clinical Implications for Surgical Approaches

Risk of Vascular Injury

Interruption of the lateral calcaneal artery during conventional lateral surgical approaches (such as for calcaneus fractures) may result in ischemic bone necrosis of the lateral calcaneus. 1

Surgical Precautions

• The lateral extensive incision for calcaneal osteosynthesis lies dangerously close to the vascular arcade 2
• Incorrect incision placement inevitably results in serious ischemic complications 2
• When performing posterior ankle approaches, identify the peroneal vascular bundle and perform dissections as distal as possible to avoid injury 3

Preoperative Planning

Incorporating peroneal artery mapping into preoperative planning is critical for high-risk procedures including posterior ankle ORIF, ankle arthrodesis, and ankle arthroscopy. 3

Contribution to Overall Foot Perfusion

Calcaneal Vascularization

The calcaneus receives blood supply from three sources 1:

• 45% medial supply: From posterior tibial artery branches below the sustentaculum
• 45% lateral supply: From lateral calcaneal artery (peroneal origin)
• 10% superior supply: From sinus tarsi artery

An intraosseous watershed zone exists in the midline where medial and lateral supplies meet 1.

Peroneal Tendon Vascularization

The peroneal artery also supplies the peroneal tendons through vincula connections 4:

• Peroneus longus tendon: No avascular areas identified
• Peroneus brevis tendon: Avascular areas present in 22.7% of specimens, particularly in the retromalleolar region 4

Assessment in Peripheral Artery Disease

When evaluating lateral foot perfusion in PAD patients:

• The peroneal artery can be assessed noninvasively with Doppler posterior to the lateral malleolus in 92% of cases 5
• Mean systolic pressure in the peroneal artery is 130.33 mmHg with corresponding ankle-brachial index of 0.92 5
• Peroneal artery pressure measurements are generally equivalent to anterior and posterior tibial arteries 5

In revascularization procedures for critical limb ischemia affecting the lateral foot, establishing in-line flow through the peroneal artery to its terminal branches is essential for wound healing and limb salvage. 6