When just one leg is affected, an infection or chronic condition like arthritis may be at work.
Treatment depends on the underlying cause.
Get Immediate Care for Sudden Swelling
Sudden swelling can be life-threatening, depending on the cause.
Illustration by Michela Buttignol for Verywell Health
It’s also key if you have other serious symptoms like heart rhythm changes or trouble breathing.
Illustration by Michela Buttignol for Verywell Health
1.
Trauma
Foot and ankle injuries are among the most common reasons for a healthcare provider visit.
Those that cause swelling include:
Those tend to be sudden injuries.
Overuse can cause swelling as well, but these injuries tend to come on more gradually.
Trauma tends to happen to one foot or ankle at a time, so only one side will swell.
Some accidents and overuse injuries may cause swelling in both.
It may affect a single joint.
Goutis another form of arthritis that typically produces a very painful, red, swollen joint.
The big toe is most common but gout can also affect the ankle or other joints in the foot.
It can affect just one ankle, or it can more widely affect the body.
Septic arthritis can prove fatal and requires immediate medical care.
Veins return deoxygenated blood (blood without oxygen) to the heart.
They may become damaged as we age and lead to swelling of the legs and ankles.
This is known asvenous insufficiency.
The most common signs include:
Things You Might Not Know About Varicose Veins
4.
Blood Vessel Blockage
Pain and swelling in one lower leg can be signs of a circulatory problem.
It is often due to inactivity.
This causes fluid to back up and can affect the ankle and foot.
In some cases, people diagnosed with PAD also have limited or disordered lymph function.
Lymphatic blockage can also contribute to ankle or foot swelling.
It can cause swelling due to the pressure which damages tissue.
Infection
Skin infection is a common cause of swelling in one foot.
It’s usually accompanied by pain and redness.
Although much less common, an infection can occur in joints even without direct trauma.
Lymphatic Blockage
Lymphedemais a swelling in your foot or lower leg due to blocked flow of lymph fluid.
This can occur due to primary lymphedema, or because of another condition that leads to the swelling.
The swelling can last for a few days after delivery.
If you have swelling during pregnancy, you should let your healthcare provider know.
Lifestyle interventions, like lying on your left side or elevating the legs, can limit symptoms.
If you suddenly begin to swell during pregnancy, you need immediate medical attention.
Compression garments often are used to treat lymphedema.
Treatment
Treatment will depend on the cause of swollen feet and ankles.
Conservative measures, such as diet and lifestyle changes, may improve symptoms.
Exercise and weight loss may help to limit lower leg edema.
Prevention
There are steps you might take to reduce and prevent swelling in the feet and ankles.
Some lifestyle changes include:
Some people may want to try techniques to help with a specific health condition.
You may experience this swelling for a variety of reasons.
Sometimes swelling may occur because of trauma or an injury.
You may have swollen ankles and feet because of arthritis or certain medical conditions.
Pregnant women may experience foot and ankle swelling as well.
Other people may have swollen ankles and feet because of a blood clot or vein problems.
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