Anatomic Classifications of the Venous System
The venous system can be broken down into four major classes. Insufficiencies can present in any of these veins, and treatment can vary depending on the classification. It is important to also understand the nervous system of the lower extremities before performing any laser vein treatment. For a full course on the anatomy of the lower limbs, AngioDynamics customers can log into our media site or anyone may take the CME/CEU course.
Deep Venous System
These are primary veins that drain venous blood from the lower extremity. They include:
- Common Femoral
- Deep femoral
- External Iliac
- Tibial (Anterior and Posterior)
Deep veins are located within the muscle fascia which allows a high volume and pressure of blood to pass through the veins. They account for approximately 90-95% of venous blood return to the heart. Deep veins can form deep vein thrombosis, or DVT, which is a dangerous clot in the deep system.
Superficial veins serve to drain blood from the skin. Blood travels from the superficial veins through the perforator veins to the deep veins. Superficial veins are located near the surface of the skin, outside of the muscle fascia, and they account for approximately 5-10% of venous blood return to the heart. There are two primary superficial veins:
- Small Saphenous Vein (SSV)
- Great Saphenous Vein (GSV)
The great saphenous vein is the longest vein in the body, running medially from the dorsal vein in the foot up to the common femoral vein in the groin, where it empties. The point where the GSV empties into the common femoral vein is called the Saphenofemoral Junction (SFJ). A typical GSV contains an average of 7 valves throughout its entire length, and it is the most common superficial vein to develop venous reflux.
The small saphenous vein originates at the back of the ankle near the outer malleous bone, and usually runs up the back of the lower leg to the popliteal vein behind the knee.
Perforator veins connect superficial veins to deep veins. They contain one-way valves to direct the blood from the superficial system to the deep system. Perforators include:
- Cockett Perforators
- Boyd's Perforators
- Dodd's Perforators
- Hunterian Perforator
Boyd's perforators are common sites for primary varicose veins. These veins connect the GSV to the posterior tibial vein. Hunterian perforators connect the GSV to the superficial femoral vein, and these are common causes of medial thigh varicosities.
- Connect branch veins to any of the deep, superficial, or perforating veins