Lymphedema is a condition whereby an excessive amount of lymph fluid collects in the legs or arms which results in swelling (edema). Lymph fluid is the small amount of fluid that exists around the cells in tissues of the body. Lymph fluid helps deliver nutrients to cells, remove waste products and remove bacteria. The lymphatic system drains the lymph fluid through small vessels that pass the fluid through lymph nodes to filter any infection and waste products before the lymph fluid drains back into the blood circulation.
Lymphedema occurs when the lymphatic system does not function properly. This can be caused by congenital anomalies, trauma, surgery, allergic reaction, wearing out of the valves and pumping mechanism of the lymphatic vessels, cancer, infection and radiation therapy. Venous insufficiency in leg veins can lead to lymphedema (veno-lymphedema). The increased venous pressure causes more lymph fluid to leave the circulation and become deposited in the tissues, thus overloading the lymphatic drainage system.
Lymphedema can be classified as two types: primary and secondary. Primary lymphedema occurs when there is an intrinsic abnormality of the lymphatic system, such as congenital abnormalities, failure of the one-way valves, or failure of the pumping mechanism. Lymphedema praecox, the development of leg swelling in young adults, is an example of primary lymphedema.
Secondary lymphedema is caused by some other issue that affects the lymphatic system. For example, breast cancer surgery and radiation therapy can damage the lymph nodes in the axilla which results in swelling of the arm. Veno-lymphedema is another example of secondary lymphedema.
Lymphedema most commonly occurs in the legs and arms and tends to be a chronic condition. Besides swelling, symptoms can include skin changes such as hardening, thickening, redness, pain, discomfort and recurrent infection.
The goal of treatment is to control the swelling. Treating any correctible problem, such as infection or venous insufficiency, is also important. Compression garments are a mainstay of treatment. Elevating the leg several times per day also helps. Sometimes a special form of physical therapy called "manual lymphatic drainage" is helpful. Pneumatic lymphatic pumps are also useful for long-term control of swelling.