The vascular system is the conduit for blood throughout the body. It consists of arteries that take blood away from the heart and divide into smaller branches. The branches continue to divide until they are a large network of tiny vessels; they are so narrow blood cells must traverse them in single file. These are called capillaries, and are where nutrients and waste are exchanged. They then become larger veins, which return blood to the heart. Problems in the vascular system in the legs can lead to weakness, nerve damage and skin infections from poor blood supply.
Peripheral Vascular Disease
Peripheral vascular disease is a circulation problem that frequently affects the legs. Symptoms may include mild numbness or tingling in the feet or toes. More severe peripheral vascular disease can cause pain with walking, called claudication. Extreme cases require amputation due to infection of the leg. Risk factors for the disease include smoking, diabetes, older age, high cholesterol and high blood pressure, according to "Harrison's Principles of Internal Medicine" by Anthony Fauci, M.D. The disease causes narrowing of the arteries in the legs, generally from the buildup of plaque, which restricts blood flow.
Deep Vein Thrombosis
This disease refers to a blood clot or multiple blood clots in the veins, typically in the legs. Blood clots cause the veins to become plugged, restricting the flow of blood from the leg back to the heart. This can cause warmth, pain and swelling in the affected extremity. Several conditions put a person at risk for a deep vein thrombosis; one of the more common risk factors comes from not moving the leg, such as during a long car or airplane ride.
Arterial Thrombosis
An arterial thrombosis is similar to a deep vein thrombosis in that it is caused by a blood clot trapped in a blood vessel and can cause circulation problems in the legs. However, an arterial thrombosis is a clot in an artery instead of a vein. Since arteries deliver blood to the tissues from the heart, this condition deprives the tissues of blood. Symptoms include pain, a lighter color of the leg from decreased blood flow, and possibly numbness or tingling, according to "Current Medical Diagnosis and Treatment" by Stephen J. McPhee, M.D. Many arterial thromboses are associated with a heart condition called atrial fibrillation, in which the atria, the top part of the heart, do not contract synchronously.
Venous Insufficiency
Venous insufficiency refers to veins that have an inadequate structure. Veins have one-way valves, allowing blood flow in the direction of the heart. If the valves become incompetent, blood can flow backwards into the leg. This can lead to swelling of the leg or legs, and dilation of veins near the surface of the legs appears as varicose veins.
References
- "Harrison's Principles of Internal Medicine"; Anthony S. Fauci et al; 17th Ed; 2008
- "Current Medical Diagnosis and Treatment" Stephen J. McPhee; 49th Ed; 2010
