Figure 1.

A general overview of the anatomy, physiology, and histology of venous system in the lower limbs. Superficial veins, mainly represented by the great and small saphenous veins, carry blood from the skin and subcutaneous tissues. Superficial veins might transport the blood through the saphenous junctions and the perforator veins to the deep venous system, the major contributors of the venous return. Deep veins are accompanied by an artery, nerves, and skeletal muscle at both sides, surrounded by a fascial compartment. Calf muscle pump is the most important source to assure an appropriated blood return from the lower limbs and it is frequently designed as the “peripheral heart”. Venous return is also permitted by the presence of venous valves, which are essential to prevent blood reflux. The cytoarchitecture of the vein comprises three main layers, intima, media, and adventitia, with unique properties.