Leg swelling can occur in any part of the legs, including the feet, ankles, calves and thighs. Leg swelling can result either from fluid buildup (fluid retention) or from inflammation in injured or diseased tissues or joints.
Many of the causes of leg swelling, such as an injury or prolonged standing or sitting, are easily identified. Sometimes leg swelling may be a sign of a more serious disorder, such as heart disease or a blood clot.
Seek medical care right away when leg swelling occurs for no apparent reason or you also have difficulty breathing, chest pain or other warning signs of a blood clot in your lungs or a serious heart condition.
Leg swelling caused by the retention of fluid in leg tissues is known as peripheral edema. It can be caused by a problem with the circulatory system, the lymphatic system or the kidneys. You may also experience swelling due to fluid buildup after sitting or standing for a long time.
Factors related to fluid buildup include:
- Acute kidney failure
- Cardiomyopathy (disease of heart tissue)
- Chronic kidney disease
- 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)
- Pain relievers, such as ibuprofen or naproxen
- Pericarditis (swelling of the membrane surrounding the heart)
- Prescription medications, including some used for diabetes and high blood pressure
- 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)
- Venous insufficiency, chronic (leg veins with a problem returning blood to the heart)
Leg swelling can also be caused by inflammation in leg tissues. Inflammation may be a normal response to injury or disease, or it may be due to rheumatoid arthritis or another inflammatory disorder. You will usually feel some pain with inflammation.
Factors that can contribute to inflammation in the leg include:
- Achilles tendon rupture
- ACL injury (tearing of the anterior cruciate ligament in your knee)
- Baker's cyst
- Broken ankle/broken foot
- Broken leg
- Cellulitis (a skin infection)
- Gout (arthritis related to excess uric acid)
- Infection or wound in the leg
- Knee bursitis (inflammation of fluid-filled sacs in the knee joint)
- Osteoarthritis (disease causing the breakdown of joints)
- Rheumatoid arthritis (inflammatory joint disease)
- Sprained ankle
Causes shown here are commonly associated with this symptom. Work with your doctor or other health care professional for an accurate diagnosis.