Sign up for our Newsletter.Why Do Varicose Veins Occur?
Like most things, it is not that simple. There are conditions that predispose you to having varicose veins like: Gender. Heredity. Trauma. Pregnancy.
Then, structural changes must occur so that venous valves lose function and allow blood to flow backwards. This causes an increase in venous pressure leading to further injury and expansion of smaller veins, medium veins, and bigger veins.
The most common place for this to happen is in the greater saphenous vein at the junction with the femoral vein in the groin. The greater saphenous vein pressure can extend all the way down to the arch of the foot affecting the veins it connects with. This increase in pressure in the great saphenous causes spider veins, blue and red feeder (reticular) veins, and veins connecting to the deep femoral vein (perforating veins) by damaging venous valves and expanding the vein wall so that the valves cannot close properly.
Healthy Vein
The pictures here demonstrate how normal blood flow and normal venous valves function by closing during diastole (the heart's rest cycle) when venous blood starts to flow backward against gravity. A normally functioning valve stops this retrograde flow, also known as venous reflux.
Damaged Vein
Damaged venous valves allow the blood to flow back and forth in both directions allowing blood to pool in the vein when the foot and leg are not in motion. Activating your calf and foot muscles can help pump the blood back towards the heart. This is why exercise, especially walking, can help temporarily improve the return blood flow to the heart.
(animations courtesy, Ben Wilson, MD, Willamette Vein Clinic)