The femoral artery represents the extension of the external iliac artery and serves to supply the lower extremity. Four English vessels and the profunda femoris artery, the deep femoral artery, branch from the artery with a cross-sectional area similar to that of the femoral artery. Because the artery runs close to the skin surface, it is often used as an access artery for a left heart catheter.
What is the femoral artery?
The femoral artery, also called the femoral artery, runs just below the inguinal ligament (ligamentum inguinale) as a direct extension of the external iliac artery (arteria iliaca externa) and passes relatively close to the surface to the popliteal fossa, which it reaches through a gap in the broad tendon of the great femoral adductor and merges with the popliteal artery, the popliteal artery. The femoral artery can be seen as a direct extension of the main coronary artery, the aorta, which branches into the two external iliac arteries at the level of the fourth lumbar vertebra. Because the femoral artery is ultimately a direct extension of the aorta and it runs superficially below the pelvis, the pulse can also be palpated on it. Branching off from the femoral artery as the main branch is the profunda femoris artery, the deep femoral artery, which has a cross-section similar to that of the femoral artery.
Anatomy and structure
The femoral artery is classified as a large blood vessel and thus belongs to the elastic artery type. Its medial wall, the media, consists largely of elastic and collagen fibers. Smooth muscle fibers, which are found in the media of the smaller arteries of muscular type, are almost entirely absent in the femoral artery. The femoral artery begins as an extension of the external iliac artery and passes under the inguinal ligament together with the femoral vein. Immediately after passing the inguinal ligament, the deep femoral artery, the external femoral artery, branches off. It has a cross-section comparable to that of the femoral artery. Four other arterial branches of small cross-section arise from the femoral artery. The four branching arteries of small cross-section may be classified as of the mixed type because their medial walls have features of the muscular and elastic types. The mediae contain smooth muscle fibers, elastic fibers, and also collagenous fibers for stabilization.
Function and tasks
The primary function of the femoral artery is to supply the leg and parts of the lower body, including the genital area, with oxygenated arterial blood, which also contains needed nutrients in dissolved form. Secondarily, the femoral artery with its elastic walls supports the Windkessel function of the aorta. The Windkessel function causes a smoothing of systolic blood pressure peaks and ensures the maintenance of diastolic residual pressure in the arteries so that the very narrow vessels, the arterioles and capillaries do not collapse and “stick together” due to adhesion forces so that they irreversibly lose their function. Specifically, the femoral artery, via its branching small arteries, supplies not only the respective leg, but other regions in the abdomen and upper abdomen, as well as large parts of the inguinal region, including the genitals. The complex network of the knee and thigh is supplied via the branching descending genal artery, also known as the descending popliteal artery. Branches of the branching great profunda femoris artery supply the musculature on the flexor side of the thigh and the femoral head. Some of the smaller arteries form so-called anastomoses with other small arteries. They connect with each other and interconnect. In the event of stenosis or complete blockage, they can each take over part of the blood supply for the defective vessel, so that tissue death does not necessarily occur immediately after a vessel blockage.
Diseases
The most common disease or condition associated with the femoral artery and its branching branches consists of deposits in the midwall of the artery. This can result in narrowing of the cross-section, stenosis, or complete blockage of the artery with the consequence that the tissues to be supplied are undersupplied. There are many reasons for the formation of deposits in the arterial walls. A disturbed cholesterol balance often plays a role.The absolute level of total cholesterol is less important than the ratio of LDL (low density lipoprotein cholesterol) to HDL (high density lipoprotein cholesterol). Ideally, the ratio should not exceed 3.5 to 4.0. In each case, these are so-called transport proteins. LDL transports cholesterol to the membranes of the vessels and HDL transports unneeded cholesterol from the vessels back to the liver. Changes in the vessel walls can also be acquired, for example, through infections, heavy smoking or chronic alcohol consumption. In less frequent cases, autosomal recessive or dominantly inherited genetic defects lead to changes in the vessel walls. The altered physical behavior of the vessel walls can, for example, promote the formation of an aneurysm, a bulging of the artery. Very rarely, aneurysm dissecans can develop in the femoral artery due to hemorrhage into the media, causing a “false” lumen to form between the inner and outer wall layers. This can also cause blockage of the artery. Accidents involving leg injuries can cause the femoral artery to be injured by external mechanical impact, resulting in severe bleeding. If the bleeding cannot drain to the outside, very large hematomas may form.