Definition
Leg swelling can affect any part of the legs. This includes the feet, ankles, calves and thighs. Leg swelling may be the result of fluid that builds up. This is called fluid buildup or fluid retention. Leg swelling also may be the result of inflammation in damaged tissues or joints.
Leg swelling is often caused by common things that are easy to identify and are not serious. Injury and standing or sitting for a long time. Sometimes leg swelling indicates a more serious problem, such as heart disease or a blood clot.
Call 911 or seek medical care right away if you have unexplained leg swelling or pain, trouble breathing, or chest pain. These could be signs of a blood clot in your lungs or a heart condition.
Causes
Many factors can cause leg swelling. Some factors are more serious than others.
Fluid buildup
Leg swelling caused by fluid buildup in leg tissues is known as peripheral edema. It can be caused by a problem with how blood travels through the body. It also can be caused by a problem with the lymphatic system or the kidneys.
Leg swelling isn’t always a sign of a heart or circulation problem. You can have swelling due to fluid buildup from being overweight, being inactive, sitting or standing for a long time, or wearing tight stockings or jeans.
Factors related to fluid buildup include:
Acute kidney injury
Cardiomyopathy (problem with the heart muscle)
Chemotherapy
Chronic kidney disease
Chronic venous insufficiency (CVI). Leg veins have a problem returning blood to the heart.
Cirrhosis (scarring of the liver)
Deep vein thrombosis (DVT)
Heart failure
Hormone therapy
Lymphedema (blockage in the lymph system)
Nephrotic syndrome (damage to small filtering blood vessels in the kidneys)
Obesity
Pain relievers, such as ibuprofen (Advil, Motrin IB) or naproxen (Aleve)
Pericarditis (inflammation of the tissue around the heart)
Pregnancy
Prescription medications, including some used for diabetes and high blood pressure
Pulmonary hypertension
Sitting for a long time, such as during airline flights
Standing for a long time
Thrombophlebitis (a blood clot that usually occurs in the leg)
Inflammation
Leg swelling also can be caused by inflammation in leg joints or tissues. Swelling can be a response to injury or disease. It also may be the result of rheumatoid arthritis or another inflammatory disorder. You’ll likely feel pain with inflammatory disorders.
Conditions that can cause inflammation in the leg include:
Achilles tendon rupture
ACL injury (tearing of the anterior cruciate ligament in your knee)
Baker cyst
Broken ankle
Broken foot
Broken leg
Burns
Cellulitis (a skin infection)
Knee bursitis (inflammation of fluid-filled sacs in the knee joint)
Osteoarthritis (the most common type of arthritis)
Rheumatoid arthritis
Sprained ankle
