Venous disease refers to all conditions related to or caused by veins that become diseased or abnormal. Venous disease is quite common — about 15 percent of the adult population is affected. Mild venous disease is usually not a problem for patients, but as venous disease worsens, it can become crippling chronic venous insufficiency.

In the normal circulation, arteries carry oxygen rich blood from your heart to the body, and veins return the blood to your heart. Veins have one-way valves along their length to keep the blood flowing to the heart. As muscles contract, the blood is squeezed forward in the veins. When muscles relax, the valves shut to prevent blood from flowing backward.

There are three types of veins in your legs: superficial veins, communicating veins, and deep veins. Superficial veins lie just under the skin and carry about 10 to 15 percent of the blood in your legs. Superficial veins drain into communicating veins, which drain into deep veins. Deep veins lie inside the muscles (remember muscles are responsible for pumping) and carry 85 to 90 percent of the blood back to the heart.

If the vein walls become weak or damaged, or if the valves are stretched or injured, the system stops working normally and the blood begins to flow backward when the muscles relax. This creates unusually high pressure in the veins, resulting in even more stretching, twisting, and swelling of veins. The abnormal veins with their sluggish blood flow create disorders known as venous disease.