The femoral vein is a large blood vessel located in the thigh. As a deep vein, its primary function is to collect deoxygenated blood from the lower leg and thigh, transporting it back towards the heart for re-oxygenation. It is part of the extensive network of veins that return blood to the heart.
Anatomy and Location
The femoral vein begins in the anterior thigh as a continuation of the popliteal vein, which originates behind the knee at the adductor hiatus. From this point, it ascends through the adductor canal and then enters the femoral triangle, an anatomical region in the upper thigh. The femoral triangle is bordered superiorly by the inguinal ligament, medially by the adductor longus muscle, and laterally by the sartorius muscle. Its floor is formed by muscles such as the iliopsoas and pectineus.
Within the femoral triangle, the femoral vein is typically found medial to the femoral artery. This relationship, along with the femoral nerve, is often remembered by the mnemonic “VAN,” representing Vein, Artery, Nerve, from medial to lateral. The femoral vein, along with the femoral artery, is encased within a fascial compartment known as the femoral sheath, though the femoral nerve lies outside this sheath. As the femoral vein continues its upward course, it passes posterior to the inguinal ligament, transitioning into the external iliac vein. This vein then proceeds into the pelvis to eventually merge with other veins, returning blood to the inferior vena cava.
Clinical Significance
The accessible location of the femoral vein makes it a frequent site for medical procedures, particularly for central venous access. Healthcare providers may insert catheters into the femoral vein to administer medications, fluids, or for monitoring blood pressure. Utilizing ultrasound guidance during these procedures is often recommended to enhance accuracy and minimize potential complications.
However, the femoral vein’s location also makes it susceptible to certain medical conditions. It is a common site for deep vein thrombosis (DVT), a condition where blood clots form in deep veins, often in the legs. A clot in the femoral vein can lead to swelling, pain, and skin discoloration in the affected limb. There is also a risk that such clots could dislodge and travel to the lungs, causing a pulmonary embolism.
Furthermore, its pathway can be affected by venous compression syndromes, where external pressure from surrounding anatomical structures can impede blood flow. May-Thurner syndrome, for example, involves the compression of the left common iliac vein (a continuation of the femoral vein) by an overlying artery, potentially leading to DVT.