Varicose veins In the healthy vein, valves allow blood to flow toward the heart,preventing the reflex of blood Gravity Great saphenous vein Valves in varicose veins are incompetent, causing blood flow inferiorly. Medial- malleolus 静脉瓣 Dorsal venous arch of footVaricose veins In the healthy vein, valves allow blood to flow toward the heart, preventing the reflex of blood. Gravity Valves in varicose veins are incompetent, causing blood flow inferiorly