Fibular (Peroneal) Artery: Anatomy, Course, Branches, Function, and Imaging

Topic

Fibular artery

The fibular artery, also known as the peroneal artery, is a major branch of the posterior tibial artery that supplies the lateral and posterior compartments of the leg. It plays a crucial role in perfusing the fibular (peroneal) muscles, tibialis posterior, and adjacent bone structures.

It runs deep within the posterior compartment, adjacent to the fibula, and provides nutrient branches to bone, perforating branches to the lateral compartment, and cutaneous branches to the skin of the lower leg and heel. The fibular artery is important in reconstructive surgery (as a pedicle for fibular free flaps) and in vascular pathologies such as peripheral arterial disease and aneurysms.

Synonyms

Peroneal artery
External branch of posterior tibial artery

Origin, Course, and Branches

Origin: Arises from the posterior tibial artery approximately 2.5–3 cm distal to the lower border of the popliteus muscle, in the posterior compartment of the leg.
Course: Descends obliquely along the medial crest of the fibula within the deep posterior compartment, lying between the tibialis posterior and flexor hallucis longus muscles. It travels inferiorly toward the ankle, deep to the fibular origin of the soleus.
Termination: Ends near the lateral aspect of the calcaneus, anastomosing with the posterior lateral malleolar and lateral calcaneal arteries.
Branches:
- Muscular branches to tibialis posterior, flexor hallucis longus, and peroneal muscles
- Perforating branch that pierces the interosseous membrane to anastomose with the anterior tibial artery
- Nutrient branch to the fibula
- Communicating branch to the posterior tibial artery
- Lateral calcaneal and malleolar branches supplying the ankle and heel

Relations

Anteriorly: Tibialis posterior and interosseous membrane
Posteriorly: Flexor hallucis longus
Medially: Posterior tibial artery (superiorly), tibialis posterior
Laterally: Fibula and fibular veins
Inferiorly: Lateral malleolus and peroneal tendons

Function

Arterial supply: Provides oxygenated blood to the lateral and posterior compartments of the leg
Nutrient role: Sends nutrient branches to the fibula and muscular structures
Collateral circulation: Contributes to anastomoses around the ankle and heel, especially important in posterior tibial artery occlusion

Clinical Significance

Peripheral arterial disease (PAD): Fibular artery often preserved when anterior or posterior tibial arteries are occluded, maintaining distal perfusion
Fibular flap surgeries: Acts as the main pedicle for vascularized fibular grafts in orthopedic and reconstructive surgery
Aneurysm and trauma: Rare but may cause compartment syndrome or ischemia
Imaging relevance: Evaluated in MRA and CTA for occlusion, stenosis, dissection, or aneurysmal changes

MRI Appearance

T1-weighted images:
- Normal artery: flow void (dark round lumen) surrounded by intermediate muscle signal
- Surrounding fat and fascia appear bright
- Thrombosed or slow-flow segments: intermediate signal replacing normal void
T2-weighted images:
- Flowing blood: signal void due to rapid flow
- Wall thickening or thrombus: hyperintense signal within vessel lumen
- Muscle: intermediate signal, darker than on T1
STIR:
- Vessel wall normally dark
- Inflammation, dissection, or edema around artery: bright hyperintense halo
Proton Density Fat-Saturated (PD FS):
- Artery: low signal lumen (flow void)
- Adjacent soft-tissue inflammation: hyperintense signal
- Useful for detecting arteritis or perivascular edema
T1 Fat-Sat Post-Contrast:
- Normal artery: bright enhancement of lumen due to intravascular contrast
- Occlusion: absence of enhancement
- Arterial wall inflammation or vasa vasorum proliferation: peripheral wall enhancement
- Helpful in vasculitis or aneurysm wall evaluation

MRA (Magnetic Resonance Angiography)

Demonstrates arterial lumen patency, caliber, and flow characteristics
Normal artery: bright signal along its course (TOF or contrast-enhanced MRA)
Stenosis or occlusion: focal narrowing or abrupt cutoff
Aneurysm: localized focal dilatation with smooth or irregular outline
Fibular flap assessment: MRA accurately maps vascular pedicle and branching pattern prior to surgery

CTA (Computed Tomography Angiography)

High-resolution visualization of arterial wall, calcification, and surrounding anatomy
Normal artery: well-opacified, bright contrast-filled lumen along fibular shaft
Occlusion or stenosis: seen as non-opacified segments or luminal narrowing
Aneurysm: saccular or fusiform dilation with contrast-filled cavity
Preoperative mapping: defines origin, course, and perforator anatomy for fibular flap harvest
Trauma evaluation: identifies laceration, thrombosis, or pseudoaneurysm formation

CT Appearance

Non-Contrast CT:

Artery appears as a small soft-tissue density beside the fibula
May show arterial wall calcification in chronic atherosclerosis
Perivascular fat planes assist in locating artery

Post-Contrast CT (standard):

Artery lumen appears bright and sharply defined
Visualizes patency, mural thickening, or contrast leak in trauma or inflammation
Useful for detecting arteritis, aneurysm, or postoperative vascular compromise

MRI images