|Varicose veins - distended, visible superficial veins on the legs - are almost always the result of problems with valves within the venous system of the leg. All leg veins contain one-way flap valves which are designed to help the flow of blood in the veins in an upward direction on its return to the heart. |
When one or more of these valves fails to function correctly ("leaks"), some blood is able to flow back down into the leg - in the wrong direction - and tends to overfill and distend branches of superficial veins under the skin. Over a period of time, this additional pressure of blood causes the veins to stretch, bulge and become visible. At the same time, tiny capillary branches of the veins are also overfilled with blood, producing multiple spider veins and purple discoloration.
"Leaky" venous valves can occur at any site in the leg but the great majority of varicose veins are caused by faulty valves in the groin or behind the knee. At both these sites there is a major junction at which superficial veins (those subject to varicose veins) flow into the important deep veins of the leg, with a one-way valve to control flow at the junction.
There is evidence that a weakness of these important valves may be inherited in some people and the valves may also be stretched and caused to leak by obesity and pregnancy. It is unlikely that prolonged standing actually causes varicose veins, although people who spend a great deal of time on their feet are certainly more likely to notice their veins and any symptoms from them.
Varicose veins is not just a problem for women, but for men also. Surgery for varicose veins should be discussed with your physician or a specialist.