The venous system of the legs
The veins in the legs form a network of vessels, consisting of superficial and deep veins. In addition, so-called perforating veins connect superficial veins to the deep ones.
Normal veins carry blood from the legs and other parts of the body back to the heart. Varicose veins are diseased veins appearing tortuous and dilated. In dilated veins, the venous valves cannot close properly. Consequently, they lose their function as valves. Then, their blood flow is inverted downwards – according to gravity.
Dilation and reversed flow – so-called “reflux,” occur mainly in the long saphenous vein (Vena saphena magna) and the short saphenous vein (Vena saphena parva) and in their branches. The deep veins – larger and more important than the aforementioned – are only rarely affected.
With a view to treatment, the long saphenous vein (Vena saphena magn) and the short saphenous vein (Vena saphena parva) and their side branches are of particular importance.