The femoral artery is a large blood vessel that provides oxygenated blood from the heart to the entire lower limb. It represents a continuation of the external iliac artery from the pelvis as it crosses into the thigh. This artery is a major component of the body’s circulatory system, functioning as the primary conduit for blood flow to the leg. Its size and accessible location near the groin make it a frequent area of medical interest.
Anatomical Placement and Structure
The femoral artery begins its course immediately below the inguinal ligament. As it passes beneath this ligament, the external iliac artery changes its name to the common femoral artery (CFA). This artery is superficially located in the upper thigh, positioned within a region known as the femoral triangle.
Within this triangle, the common femoral artery is contained within a protective layer called the femoral sheath, alongside the femoral vein. After a short distance, the common femoral artery typically divides into two main branches: the deep femoral artery (or profunda femoris) and the superficial femoral artery. The superficial femoral artery continues down the length of the thigh, eventually becoming the popliteal artery behind the knee.
Measured Dimensions and Range of Variation
The size of the femoral artery is substantial, reflecting its role as the main supplier of blood to the large muscles of the leg. The common femoral artery in healthy adults typically has an average diameter ranging from approximately 6.6 millimeters to 9.4 millimeters, with reported values often falling around 7 to 8 millimeters.
This measurement, however, is not a fixed number and a healthy range of variation exists among individuals. Factors like sex and overall body size play a significant role in determining the artery’s dimensions. Generally, the common femoral artery is found to be larger in males than in females, and its size correlates positively with a person’s height, weight, and body surface area.
The artery’s diameter also increases with age. Conditions such as diabetes or obesity can also influence the size of the artery, with some studies indicating that chronic diseases may be associated with smaller vessel sizes. This natural variability underscores why there is no single “correct” measurement, but rather a wide, healthy range.
Primary Function in Lower Body Circulation
The primary physiological role of the femoral artery is delivering oxygen-rich blood to the entire lower extremity. Once the common femoral artery divides, its branches supply various parts of the leg. The deep femoral artery mainly supplies the muscles of the thigh and hip, providing blood flow for powerful movements.
The superficial femoral artery continues the flow down the leg, supplying the lower leg and foot after it transitions into the popliteal artery. This massive volume of blood is necessary to fuel the large muscle groups required for locomotion. The circulatory system also includes a network of smaller vessels, known as collateral circulation, which serves as backup routes. These collateral pathways can provide alternative blood flow to the lower limb if the main femoral artery becomes partially blocked.
Importance in Medical Procedures and Diagnosis
The femoral artery’s size and superficial location in the groin are highly significant in modern medicine, making it a preferred vascular access site. Its large diameter allows for the insertion of catheters and specialized instruments for various procedures, including angiography and stent placement. This access point is particularly favored in interventional cardiology, as it provides a direct, relatively straight path to the central vasculature and the heart.
The artery’s location, which allows it to be compressed against the underlying bone, is also an advantage for achieving hemostasis after a procedure. Changes in the artery’s size are also a major diagnostic focus for conditions like peripheral arterial disease (PAD). Narrowing of the artery due to plaque buildup, known as stenosis, restricts blood flow and can lead to pain and tissue damage in the leg.
Conversely, an abnormal widening of the artery, called an aneurysm, can be a serious concern due to the risk of rupture. Regular assessment of the femoral artery’s diameter and flow is therefore a standard part of diagnosing and managing vascular health issues. The common femoral artery is also the site of choice for procedures requiring large-bore catheters, such as those used for certain heart valve implants, further highlighting its unique medical importance.