What Causes Ankle and Feet Swelling, What Should I Do?

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Swollen feet ankle

Vein physician and chronic venous insufficiency (CVI) expert Laura Kelsey, MD, outlines the causes for swelling of the lower extremities. She offers guidance about what to do if you are experiencing unexplained swelling. She is the lead physician at Center for Vein Restoration center locations in Grand Rapids, MI, and Norton Shores, MI.

Center for Vein Restoration (CVR) vein disease doctor Laura Kelsey, MD, explains the many possible reasons for swelling of the ankles and feet. These can be divided into a) sudden onset of swelling caused by a provoking event and b) slow onset swelling without a provoking event.

Sudden onset (acute) swelling caused by injury

Acute swelling is usually found in one place in the body and the person generally knows the reason for the pain or swelling. Causes can include arthritis, sprain, traumatic or sports-related injuries.

Acute onset of pain and swelling following surgery or travel should raise immediate concern for a blood clot.

Slow onset swelling or unexplained swelling

Swelling that is unexplained in one or both legs is more difficult to identify. Causes could include medical conditions such as; heart disease, kidney, liver or thyroid disease, inactivity, dietary factors such as too much sodium, not enough water, obesity, or pregnancy.

In addition, venous insufficiency (vein disease) and lymphedema (swelling due to build-up of fluid in the body) should be considered.

Swelling can be a cause for concern, says Dr. Kelsey. When swelling is sudden and for no apparent reason, does not resolve quickly, progressively gets worse, or is associated with other symptoms, such as pain in the leg or feet, shortness of breath, blood clot is a major concern.

“If someone is experiencing swelling associated with pain, swelling that doesn’t get better, is unilateral (one-sided), associated with shortness of breath, chest pain, or skin discoloration, they must seek a doctor’s care immediately. If the swelling is associated with an event such as recent surgery or travel, this could be related to blood clots and should also be treated as a medical emergency.” -Dr. Laura Kelsey

Causes for Ankle and Foot Swelling

Venous insufficiency

As you breathe and walk, blood moves toward the heart. When gravity pulls, the valves open to prevent the blood from pooling in the legs and ankles. Venous insufficiency occurs when these valves fail, allowing blood to flow backward and pool.

Improperly functioning or defective leg veins are a common cause of swelling. By age 50, approximately 50 percent of women will have this problem, says Dr. Kelsey.

Sometimes the defective veins can be seen on the legs as varicose veins or spider veins. Other times these poorly functioning veins are deeper in the legs and are not visible.

In these cases, the person may have swelling that gets progressively worse or causes changes to the color or texture of the skin. Often patients will complain of tired, heavy, achy legs, adds Dr. Kelsey.

Dr. Kelsey emphasized the importance of an ultrasound to determine the function of the valves within the venous system (that is, the network of veins in the legs that work to bring blood back to the heart).

If the ultrasound does not show that these valves have failed (known as venous insufficiency), there may be reasons other than venous insufficiency for the swelling. These include:


Walking and exercise are important for the blood flow back to the heart. The calf muscle is a pump that pushes the fluid toward the heart in the deep veins.

If a person is not physically active, fluid can build and cause swelling. Those who are disabled or those who sit for long periods for work or travel, and those who don't work their calf pump with exercise can be affected.

Blood clot

Deep Vein Thrombosis (DVT) is a medical emergency and should be addressed immediately. Symptoms include severe and sudden swelling and pain. Risk factors for clots include recent surgery or hospitalization, long travel, family history of blood clots, birth control pills, cancer, and pregnancy.

In addition, people with a history of previous blood clots can develop post-thrombotic syndrome, where there is permanent damage to the deep veins in the leg.


Lymphedema is a progressive condition that can start as a little swelling at the end of the day. A few years later, it may progress to swelling earlier in the day. Eventually, it can lead to even in the morning following a night of elevation. Skin infections can occur at this stage.

If untreated, lymphedema can get so bad that clear fluid actually weeps out of the leg through the skin. Lymphedema can occur after lymph nodes are removed or exposed to radiation; it can follow major surgery or trauma to the limb, and often, the specific cause is unknown.

It is a condition that gets worse over time and is hard to recognize in the early stages. Early management with compression and manual lymphatic drainage massage is critical to prevent the progression of this condition.

Other abnormalities

Dr. Kelsey recommends that anyone experiencing swelling that seems to be getting worse speak to their doctor to check on heart, kidney, thyroid, or liver function.

Can ankle or foot swelling be reduced at home?

If a person is experiencing swelling not caused by injury or a blood clot, Dr. Kelsey recommends:

  • Walking – Moving the muscles helps pump excess fluid back toward the heart.
  • Compression – Snug compression stockings provide support and pressure to the lower extremities, preventing fluid from pooling, and structural supports the veins system.
  • Reducing sodium intake – Salt can increase fluid retention and worsen swelling.
  • Drink plenty of water – 8 to 10 glasses of water a day.
  • Elevation – keep legs slightly higher than the heart when sitting or sleeping.
  • Consider the medications you’re taking – NSAIDs, estrogen, calcium channel blockers, some anti-depressants, and diabetes medicines can cause swelling. Speak to your doctor before changing any medication regimen.

When should a person see a vein specialist?

If swelling persists after other causes are ruled out, a visit to a vein specialist is in order. This specialist will perform a diagnostic ultrasound to look for signs of venous insufficiency or early lymphedema and guide patients in treatment options.

Dr. Kelsey says that she explains normal physiology and describes to her patients why weakened vein valves cause swelling, pain, varicose veins, skin discoloration, and leg ulcers.

How to diagnose swelling caused by improperly functioning leg veins

Venous insufficiency is diagnosed using a mapping ultrasound. During this thorough yet painless ultrasound, the technician will “view” the veins and test their function to identify any abnormalities in the blood flow throughout the leg. Mapping the veins “helps us to understand the flow in the veins and by testing the valves in both the deep and superficial veins,” says Dr. Kelsey. Ultrasound mapping can tell the vein doctor if venous insufficiency is the cause of the patient’s swelling.

Treatment for chronic venous insufficiency

Since vein disease runs in families, stories of painful, invasive treatments from the past are passed down through the generations, says Dr. Kelsey. Luckily, these old procedures have been replaced with new minimally invasive techniques that are office-based and require little to no downtime. These include non-surgical injections such as ablation (radiofrequency and laser, Varithena, Venaseal, ambulatory phlebectomy, and sclerotherapy.

Is leg swelling a problem? Schedule an appointment with a vein specialist

Call 240-965-3915 or visit centerforvein.com for more information or to schedule an appointment. Whether your foot and ankle swelling is acute or persistent, don't wait to seek medical advice. Treatment is covered by most major insurance providers, including Medicare and Medicaid.

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