Understanding the Iliac Artery: Anatomy, Function, and Vascular Health
Updated: 2 days ago
Medically reviewed by Dr. Baraa Alnahhal, MD | Last reviewed: October 7, 2026
Quick Answer: What is the iliac artery?
The iliac artery is a major paired blood vessel that branches from the base of the abdominal aorta near the navel. [1] It is the main route for oxygenated blood traveling to the legs, pelvic floor and reproductive organs. [1] Each common iliac artery divides into internal and external branches, delivering nutrients to the core muscles, pelvic structures and legs. [1]
What the research says
Peripheral artery disease, which can arise from plaque in the iliac arteries, affects hundreds of millions of people and rises steeply with age. A systematic review and analysis of 118 articles estimated that 5.56% (95% CI 3.79–8.55) of people aged 25 and older, about 236.62 million people, were living with peripheral artery disease in 2015. Prevalence at ages 80–84 reached 21.24% in high-income countries and 12.04% in low- and middle-income countries, and smoking, diabetes, hypertension and high cholesterol were major risk factors (Song et al., The Lancet Global Health, 2019) [2].
Supervised-style exercise programs help people with leg pain from PAD walk farther. A Cochrane review of 32 randomized trials (1,835 participants) found that exercise improved pain-free walking distance by 82.11 m (95% CI 71.73–92.48; 9 studies, 391 participants; high-quality evidence) and maximum walking distance by 120.36 m (95% CI 50.79–189.92; 10 studies, 500 participants; high-quality evidence) compared with no exercise. Exercise did not improve the ankle-brachial index, and no effect on mortality or amputation was shown (Lane et al., Cochrane Database of Systematic Reviews, 2017) [3].
Walking-distance medicine for claudication gives only a small gain and has side effects. A Cochrane review of 16 double-blind trials (3,972 participants) found that people taking cilostazol walked 26.49 m farther before leg pain began than those taking placebo (95% CI 18.93–34.05; low-certainty evidence), with higher odds of headache (OR 2.83, 95% CI 2.26–3.55), and there was too little evidence on amputation, revascularisation or cardiovascular events (Brown et al., Cochrane Database of Systematic Reviews, 2021) [4].
Overview
The iliac arteries represent a vital junction in the human circulatory system. As peripheral vessels, they are responsible for transporting oxygen-rich blood from the heart to the regions of the body furthest from the chest, specifically the lower torso and legs. [1] Understanding their complex structure and the conditions that affect them is essential for maintaining long-term vascular health and physical mobility.
Anatomy and Functional Branches
The common iliac arteries begin their journey in the midsection, branching directly from the lower end of the aorta. [1] Each artery travels approximately four centimeters before bifurcating into two distinct channels: the internal and external iliac arteries. [1] These branches further divide to ensure that even the most remote tissues in the lower body receive a consistent blood supply.
The external iliac artery is the larger of the two primary branches and eventually transitions into the femoral artery as it enters the leg. [1] It is the principal source of blood for the feet and legs. [1] Meanwhile, the internal iliac artery focuses on the pelvic interior, distributing blood to the reproductive systems, the rectum, and the muscles of the hips and thighs. [1]
Artery Branch | Primary Function and Target Areas |
Common Iliac | Originates from the abdominal aorta; acts as the main trunk for lower body blood flow. |
External Iliac | Supplies the legs and feet; branches into deep circumflex and inferior epigastric arteries for core muscles. |
Internal Iliac | Supplies pelvic organs, reproductive systems, the rectum, and the pelvic floor. |
Common Conditions and Vascular Risks
Like many major blood vessels, the iliac arteries are susceptible to various disorders that can impede blood flow. The most common issue is atherosclerosis, where deposits of fat and cholesterol, known as plaque, accumulate along the arterial walls. [1] This narrowing of the vessel can lead to peripheral artery disease (PAD), a condition that often manifests as significant leg pain during physical activity. [1] [3] [4]
Beyond plaque buildup, some individuals may experience iliac artery stenosis due to rare conditions like fibromuscular dysplasia. [1] This causes the arteries to become stiff and narrow, increasing the risk of dissections or aneurysms. [1] Additionally, May-Thurner syndrome can occur when the right common iliac artery compresses the left common iliac vein against the spine, potentially leading to deep vein thrombosis. [1]
Condition | Clinical Impact and Risks |
Atherosclerosis | Plaque buildup that narrows the artery and restricts oxygen delivery. |
Peripheral Artery Disease | Results from narrowed arteries; increases risks of heart attack, stroke, and amputation. |
Iliac Artery Stenosis | Stiffening of the vessel walls; may lead to arterial tears or bulging aneurysms. |
May-Thurner Syndrome | Venous compression leading to an increased risk of blood clots in the legs. |
Strategies for Vascular Care and Prevention
Maintaining the integrity of the iliac arteries involves a combination of proactive lifestyle choices and medical management. Because these vessels are highly sensitive to systemic health factors, controlling underlying conditions such as diabetes, high blood pressure, and high cholesterol is paramount. [1] [2] Regular physical activity and a heart-healthy diet low in saturated fats and salt provide the foundation for keeping these pathways clear. [1]
Smoking cessation is perhaps the most significant single step an individual can take to protect their arterial health. Tobacco use significantly accelerates plaque formation and weakens vessel walls. Furthermore, managing stress through activities like meditation or walking [1] can help maintain stable blood pressure, reducing the mechanical strain on the iliac system.
Conclusion
The iliac arteries are indispensable components of the circulatory network, providing the life-sustaining blood flow required for movement and organ function in the lower body. By recognizing the warning signs of vascular distress—such as persistent leg pain or non-healing wounds—and committing to a cardiovascular-friendly lifestyle, individuals can significantly reduce their risk of serious complications and maintain their quality of life.
Take Action for Your Health
If you experience persistent pain when walking or resting, or if you notice sores on your feet that do not seem to heal, consult a healthcare professional immediately. Early detection of circulation issues through non-invasive testing can lead to more effective management and better long-term outcomes.
Frequently Asked Questions
Where exactly are the iliac arteries located?
The iliac arteries are located in the lower abdomen, starting near the navel where the abdominal aorta ends.
What is the difference between the internal and external iliac arteries?
The external branch primarily supplies the legs, while the internal branch supplies the pelvic organs and reproductive systems.
What are the core muscles supplied by the iliac system?
The external iliac artery provides blood to the oblique, transverse abdominus, and rectus abdominus muscles.
How long is the common iliac artery before it branches?
The common iliac artery typically travels about 4 centimeters (roughly 1.5 inches) before dividing.
What is peripheral artery disease (PAD)?
PAD is a condition where plaque buildup narrows the arteries, reducing blood flow to the limbs.
Why does PAD cause pain during walking?
The narrowed arteries cannot deliver enough oxygenated blood to the leg muscles when they are working hard.
What is May-Thurner syndrome?
May-Thurner syndrome is a condition where the right common iliac artery compresses the left common iliac vein against the spine.
Can iliac artery problems increase the risk of a heart attack?
Yes, conditions like PAD are systemic indicators of vascular health and are linked to higher risks of heart attack and stroke.
What is fibromuscular dysplasia (FMD)?
FMD is a rare disease that causes the artery walls to become stiff and narrow.
What are the symptoms of an iliac artery aneurysm?
Aneurysms often have no symptoms until they become large or tear, though they represent a weak, bulging spot in the wall.
How does smoking affect the iliac arteries?
Smoking damages the lining of the arteries and accelerates the accumulation of plaque.
What kind of diet supports iliac artery health?
A heart-healthy diet low in fat, cholesterol, and salt is recommended.
Are there non-invasive tests for iliac artery health?
Yes, healthcare providers can use simple tests to measure blood flow through the legs.
What are the warning signs of poor circulation in the feet?
Non-healing wounds or sores on the feet are common indicators of inadequate blood supply.
At what age are iliac artery problems most common?
While they can occur earlier, PAD and related issues most frequently affect individuals over the age of 65.
Related Reading
Aortoiliac Occlusive Disease Explained: Symptoms, Causes, and the Treatment Ladder explains blockages in the aorta and iliac arteries and their treatment.
Peripheral Artery Disease (PAD): Symptoms, Causes, Diagnosis & Treatment Options covers narrowed leg arteries, warning signs and treatment options.
Abdominal Aortic Aneurysm (AAA): Complete Guide to Symptoms, Causes, Screening, and Treatment Options describes bulging of the aorta just above where the iliac arteries begin.
What Is Claudication? Why Your Legs Hurt When You Walk, and What to Do About It explains leg pain with walking caused by reduced blood flow.
Sources
Cleveland Clinic. Iliac Artery. Cleveland Clinic. Last updated August 4, 2021. https://my.clevelandclinic.org/health/body/21681-iliac-artery
Song P, Rudan D, Zhu Y, et al. Global, regional, and national prevalence and risk factors for peripheral artery disease in 2015: an updated systematic review and analysis. Lancet Glob Health. 2019;7(8):e1020-e1030. PMID 31303293. https://doi.org/10.1016/S2214-109X(19)30255-4
Lane R, Harwood A, Watson L, et al. Exercise for intermittent claudication. Cochrane Database Syst Rev. 2017;12(12):CD000990. PMID 29278423. https://doi.org/10.1002/14651858.CD000990.pub4
Brown T, Forster RB, Cleanthis M, et al. Cilostazol for intermittent claudication. Cochrane Database Syst Rev. 2021;6(6):CD003748. PMID 34192807. https://doi.org/10.1002/14651858.CD003748.pub5
Medical disclaimer
The information provided in this article is for educational purposes only and is not intended as medical advice. Always seek the guidance of a qualified healthcare provider regarding any medical condition or treatment.
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