Swelling of the legs and ankle, or peripheral edema, is the result of a sudden injury or an underlying medical condition such as kidney, liver or heart disease. Gravity also naturally pulls fluids to the lower extremities, thus standing or sitting for a prolonged period of time results in an abnormal accumulation of fluids in the tissues of the legs and ankles.
Rheumatoid Arthritis
Rheumatoid arthritis is an autoimmune, inflammatory disorder characterized by a symmetric swelling and stiffness of the joints. In rheumatoid arthritis, the immune system produces antibodies that target and destroy joint tissue, primary those of the knees, hips, shoulders, wrists, ankles and elbows. This autoimmune disorder usually affects the joints on both sides of the body, resulting in pain, stiffness, weakness and swelling. The autoimmune antibodies cause an inflammation of the synovial lining of the joints, resulting in intermittent fluid accumulation and swelling in the legs, ankles and feet. According to the American Academy of Orthopaedic Surgeons, 90 percent of individuals diagnosed with rheumatoid arthritis develop peripheral edema in the legs and ankles.
Pregnancy
Swelling of the legs and ankles is a symptom commonly associated with pregnancy, notes MayoClinic.com. During pregnancy, the growing uterus and embryo applies pressure to the veins impairing the venous return of blood from the lower extremities to the heart. The addition of pressure to the veins results in the accumulation of fluid in the interstitial space, resulting in swelling of the legs, feet and ankles. During pregnancy, women usually gain more weight and the body produces and accumulates more fluids, resulting in peripheral edema. Pregnant women are advised to reduce their salt intake, avoid crossing legs to prevent the further application of pressure on the veins and avoid standing or sitting for prolonged periods of time.
Prolonged Standing or Sitting
According to MedlinePlus, prolonged sitting or standing can result in swelling of the legs and ankles. Gravity is a force that naturally pulls fluids towards to the lower extremities. Prolonged standing and sitting results in the accumulation of fluid in the interstitial space in the tissues of the legs and ankles. Swelling of the legs and ankles can be prevented by shifting position or moving around. Reducing salt intake, elevating the legs above heart level, taking a diuretic or water pill and wearing compression stocking can help reduce swelling in the legs and ankles.
