Lateral Calcaneal Artery: Anatomy, Course, Branches, and Imaging

Topic

Lateral calcaneal artery

The lateral calcaneal artery is a major branch of the peroneal (fibular) artery that supplies the lateral and posterior aspects of the heel. It provides important vascularization to the calcaneus, Achilles tendon, and heel skin, playing a key role in the posterior ankle’s collateral circulation.

This artery is clinically significant because it is frequently involved in traumatic heel injuries, flap reconstruction, and vascular compromise in diabetic foot disease. It is an essential structure for posterior heel flap surgeries and is evaluated in peripheral arterial disease (PAD) and heel ulcer management.

Synonyms

Lateral branch of the peroneal artery
Lateral heel artery
Fibular calcaneal branch

Origin, Course, and Branches

Origin: Arises from the peroneal (fibular) artery, near its termination in the distal leg.
Course: Passes posterolaterally behind the lateral malleolus, running obliquely toward the lateral aspect of the heel.
Branches:
- Cutaneous branches: Supply the lateral and posterior skin of the heel.
- Muscular branches: Supply peroneal muscles and the calcaneal tuberosity.
- Anastomotic branches: Communicate with the medial calcaneal branches of the posterior tibial artery and the plantar arterial network.
Termination: Ends by supplying the lateral surface of the calcaneus, heel pad, and surrounding fascia.

Relations

Superiorly: Peroneal muscles (peroneus longus and brevis).
Inferiorly: Lateral surface of the calcaneus.
Anteriorly: Lateral malleolus and peroneal tendon sheath.
Posteriorly: Achilles tendon and calcaneal bursa.
Medially: Posterior tibial neurovascular bundle (deep plane).
Laterally: Skin and subcutaneous tissue of the heel.

Arterial Supply Context

Major contributor to the calcaneal arterial plexus.
Anastomoses with:
- Medial calcaneal arteries (posterior tibial origin).
- Plantar arteries (lateral plantar artery).
- Perforating branch of the peroneal artery (anterior connections).
Supports blood flow to the Achilles tendon and posterior heel skin, especially critical in reconstructive surgery.

Function

Vascular supply: Provides blood to lateral and posterior heel skin, subcutaneous tissue, and calcaneal bone.
Collateral circulation: Assists in maintaining foot perfusion during tibial or peroneal artery compromise.
Clinical role: Important in flap design, wound healing, and evaluating heel ischemia.

Clinical Significance

Trauma: May be injured in fractures or lacerations of the heel and lateral ankle.
Atherosclerosis / PAD: Reduced perfusion may contribute to heel ulcers and delayed wound healing.
Surgical relevance: Used as a vascular landmark for reverse sural and lateral calcaneal flaps.
Imaging importance: MRA and CTA used to evaluate its patency in diabetic foot, trauma, or bypass planning.

MRI Appearance

T1-weighted images:
- Vessel lumen: flow void (dark linear signal) due to fast flow.
- Adjacent fat planes: bright signal outlining the artery.
- Surrounding muscles (peroneals, Achilles): intermediate signal intensity.
T2-weighted images:
- Artery appears as a dark tubular structure surrounded by high-signal soft tissue.
- Inflammation or edema around the vessel: bright hyperintense rim.
- Thrombosis: loss of flow void with intermediate intraluminal signal.
STIR:
- Normally dark linear structure.
- Surrounding edema, cellulitis, or vascular inflammation: bright signal enhancement.
Proton Density Fat-Saturated (PD FS):
- Vessel: dark linear void.
- Surrounding fat and fascia: suppressed, improving arterial contrast.
- Vessel wall thickening or adventitial inflammation: mild bright signal.
T1 Fat-Sat Post-Contrast (Normal Axial View):
- Lateral calcaneal artery shows bright linear enhancement along its course behind the lateral malleolus toward the heel.
- Perivascular enhancement may indicate vasculitis, hyperemia, or infection.
- Clear visualization of the artery in contrast to low-signal muscle and bright perivascular fat.

MR Angiography (Contrast-Enhanced MRA)

The lateral calcaneal artery enhances brightly as a small yet distinct branch of the distal peroneal artery.
Best seen on 3D contrast-enhanced MRA or time-resolved MRA sequences.
Demonstrates its course posterolateral to the calcaneus and anastomotic connections with medial calcaneal and lateral plantar arteries.
Pathological findings:
- Occlusion: Segmental non-visualization or reduced caliber.
- Aneurysm: Focal dilatation with peripheral mural enhancement.
- Collateralization: Increased branching in chronic ischemic cases.

CT Appearance

Non-Contrast CT:

Artery not directly visualized due to small caliber.
May appear as a faint soft-tissue density posterior to the lateral malleolus.
Calcified plaques visible in chronic atherosclerosis.

Post-Contrast CT (CTA):

CTA is the imaging gold standard for identifying and tracing the lateral calcaneal artery.
Artery appears as a bright enhancing tubular structure arising from the distal peroneal artery.
3D volume-rendered CTA shows its course posterior to the lateral malleolus and around the heel.
CTA Findings:
- Occlusion: Abrupt cutoff or non-opacified segment.
- Aneurysm: Saccular outpouching with intense enhancement.
- Post-traumatic pseudoaneurysm: Contrast extravasation in soft tissue.
- Atherosclerosis: Irregular luminal narrowing, mural calcification, or distal pruning.