Varicose veins (varicosities) are the over dilation of the superficial veins in the legs. Two networks of veins in the legs move the blood from the feet back to the heart. One is superficial, lying just under the skin, while the other system of veins is deep in the muscles. The superficial venous system may dilate to form varicose veins.
Muscle contractions in the leg squeeze the veins, and with the aid of one-way valves scattered through the network, the blood is steadily pushed back towards the heart. Pregnancy (because the growing baby puts pressure on veins in the pelvis) and prolonged standing (eg. hairdressing, shop assistant) make it difficult for the blood to move up from the legs into the body and the pooled blood stretches the veins, which then damages the one-way valves. The damaged valves allow more blood to remain in the veins, stretching them further. Reducing the amount of standing, wearing elastic support stockings and regularly exercising the muscles in the legs while standing may prevent varicose veins.
Sufferers develop tired, aching, swollen legs, with large, ugly, blue, knotted veins under blotchy, red and sometimes ulcerated skin. Rupture of a vein may cause severe bruising, or a cut will bleed profusely (treated by elevating the leg and applying compression).