Causes of Ankle and Lower Leg Swelling

Ankle and Lower Leg swelling has many different causes. 27 different possible causes per MayoClinic and if you believe symptoms are serious, seek medical attention.

Ankle and lower leg swelling has many different causes 1. cites 27 different possible causes 1. A patient might have ankle swelling from a minor problem, such as prolonged standing, or from a serious medical condition such as heart failure 1. It is important for the patient to understand some of the common reasons for ankle and leg swelling 1.

Heart Failure

The heart is the main organ for pumping blood and fluids through a person's body. One of the early signs of heart failure is ankle and lower leg swelling, and this tends to occur on both legs 1. If a patient is over age 35 and develops bilateral ankle swelling, without trauma, she should see a physician to get checked for possible heart failure 1.

Kidney Failure

The kidneys represent the filtration system for the human body. They filter out waste products and also aid the heart in circulation of fluids. A patient who is experiencing kidney failure will often develop swelling in the lower extremities; this will then spread to other parts of the body as the kidney failure progresses 1. This also warrants close management by a physician.

Vein Disease

Veins are the bluish-colored blood vessels that bring old blood from the arms and legs back to the heart. When the veins get damaged and weak, a patient may develop a disease known as "venous insufficiency." Venous insufficiency is a common cause of lower extremity swelling in the elderly 1.

Blood Clot in Leg

Though not common, a blood clot in the deep veins of a patient's leg can be lethal. Such a condition is termed "deep vein thrombosis," or DVT. In addition to lower leg swelling (usually unilateral), a DVT patient will have pain and redness in the calf area 1. Such a set of symptoms warrants immediate medical attention.

Ankle and Leg Injuries

Trauma is a frequent cause of ankle and lower leg swelling, but the patient is usually aware of his injury 1. Examples include: sprain or fracture of the ankle, torn Achilles tendon or contusion injury of the foot. A strained calf muscle will also cause lower leg swelling 1.


Cellulitis is a bacterial infection of the skin and underlying soft tissues. If cellulitis occurs on a patient's lower extremity, she will have local swelling as well as pain and warmth 1. Such symptoms warrant a visit to her physician, so that she can start on antibiotic treatment.

Dependent Edema

When a person sits or stands too long in a fixed position, this causes a backup in the circulatory and lymphatic system, which causes leg and ankle swelling 1. This is known as "dependent edema." A typical example is when a man is flying on a 12-hour overseas flight, and he is stuck in a middle seat on economy class. Ankle exercises, massage and frequent visits to the lavatory will help avert this problem.