What is trench foot?
Trench foot, or immersion foot syndrome, is a condition that can occur when your feet are cold and wet for a long period of time. It often happens when you have to wear wet socks and shoes or boots for days at a time. Prolonged exposure to damp, cold and sometimes unsanitary conditions can lead to the disease.
Trench foot is a type of non-freezing cold injury. This means the temperature that causes the condition is usually cold but above freezing. Other non-freezing cold injuries include chilblains, frostnip and Raynaud’s phenomenon. Trench foot can cause skin and tissue breakdown, which can increase your risk for infection. The condition can be very painful, but it’s treatable and preventable.
Where did trench foot get its name?
In 1812, a French army surgeon first described trench foot when treating soldiers in Napoleon’s army. But it became well known during World War I when many soldiers developed the condition. The soldiers stood in waterlogged trenches for long periods and had to endure cold, wet and muddy conditions. More than 20,000 British troops were treated for trench foot between 1914 and 1915. Fortunately, today, prevention and treatment options are available. However, the condition still does occur.
Who does trench foot affect?
Trench foot most commonly affects people in the military during training and combat operations. But trench foot can affect other groups of people. Trench foot affects:
- People who are homeless: People who are homeless often don’t have more than one pair of socks and shoes. They lack shelter and endure long periods of wet and cold.
- People who attend music festivals: People who go to large, outdoor music festivals can develop trench foot by standing in cold, wet and unsanitary conditions for days at a time.
- People who work in or near water: Fish processors, harbor workers and other people who have to stand in water for an extended time for their jobs may develop trench foot.
- People who spend time outdoors: People who enjoy recreational activities such as hiking and mountaineering can develop trench foot if they neglect to change out of wet socks and boots.
Symptoms and Causes
What are the symptoms of trench foot?
Trench foot looks and feels different as the disease develops.
The first symptoms of trench foot include tingling and itching which can progress to numbness. Your feet may feel prickly or heavy, like blocks of wood. Because of this, you may have difficulty walking. Your feet may be bright red. But they’ll soon turn pale, clammy and white as your blood vessels narrow.
Once you’re out of the cold, the skin of your feet will start to change color. If your skin is lighter, it may look blue or purple due to poor blood flow. If you’re darker skinned, the discoloration won’t be as noticeable. Your skin may be cold and blotchy. In addition, you may develop swelling. In severe cases, your feet can almost double in size.
As your feet rewarm, they may become bright red again. You may experience extreme pain or an abnormal sensation as blood flow returns to your feet. You may also develop blisters and holes or open sores on your feet, which can lead to fungal and bacterial infections. Your skin may become overly sensitive to changes in temperature and the lightest touch.
What causes trench foot?
You get trench foot by standing in wet, cold conditions for an extended period of time. The temperature doesn’t have to be freezing. Trench foot can develop in temperatures up to 60°F (16°C).
When cold temperatures and moisture combine, small blood vessels (capillaries) in your feet can start to weaken. This can lead to damage of the surrounding tissue. In addition, restricted blood flow affects your circulation and nerve function.
Excessively sweaty feet (hyperhidrosis) can also cause trench foot.
How long does it take to get trench foot?
Most cases of trench foot require exposure to cold, wet conditions for one to three days. But you can get trench foot in as little as 10 to 14 hours.
Diagnosis and Tests
How is trench foot diagnosed?
Your healthcare provider will perform a physical examination to diagnose trench foot. They’ll examine your foot and ask you about your symptoms. They’ll also ask you about your recent history. If you’ve been exposed to a cold, wet environment for at least a few hours, they may diagnose trench foot.
Your healthcare provider will want to make sure your symptoms aren’t the result of an infection or another condition such as frostbite. They may order a white blood cell count or a sed rate (erythrocyte sedimentation rate or ESR) test. A sed rate test looks for inflammation in your body. Your healthcare provider may also order an X-ray or a bone scan if they think you may have a bone infection (osteomyelitis).
Management and Treatment
Is there a cure for trench foot?
Yes. Trench foot is treatable if caught early. Treatment for trench foot includes gentle rewarming of your foot. Rapid rewarming can cause severe pain and swelling. To get rid of trench foot, your healthcare provider will also clean your foot and keep it dry and warm. Additional treatment includes resting and elevating your foot above your heart. This can help prevent new wounds and blisters.
Your healthcare provider may prescribe an antibiotic to prevent any infections. You may receive a tetanus booster shot. For pain, you can take nonsteroidal anti-inflammatory drugs (NSAIDs) or acetaminophen. But your healthcare provider may prescribe a medication called amitriptyline.
How can I take care of myself after treatment for trench foot?
After treatment for trench foot, you’ll need to take certain steps to make sure your foot continues to heal. These steps include:
- Making sure to wear a clean, dry pair of socks every day.
- Avoiding wearing socks while sleeping to keep your feet dry.
- Checking your feet daily to make sure your symptoms aren’t worsening or you’re not developing any possible infections.
- Avoiding smoking and using other products containing nicotine. Nicotine can impair blood flow to your foot.
- Eating a diet high in protein.
How can I prevent trench foot?
Trench foot is very preventable. The following precautions may help prevent you from developing the condition:
- Change out of wet socks and shoes/boots as soon as possible.
- Let your feet air-dry and make sure your feet stay dry.
- Keep your feet elevated when possible.
- Change into a new pair of socks at least once a day.
- Wear properly fitting boots or shoes.
Outlook / Prognosis
What can I expect if I have trench foot?
In the past, trench foot was a serious condition that could lead to death. Today, most cases of trench foot are curable with early diagnosis and treatment. You can expect to fully recover from the condition. However, you may still have some lingering pain as full sensation returns to your foot.
What complications can trench foot cause?
If left untreated, cellulitis or gangrene can set in. In severe cases, gangrene may lead to the need for amputation to avoid further disease progression. Other complications can include sepsis and death.
A note from Cleveland Clinic
Trench foot is a painful condition that got its name from the trenches WWI soldiers had to stand in. At that time, many soldiers lost their limbs and even died because of the condition. Today, prevention and treatment options are well known. The best treatment for trench foot is actually prevention. If you know you’re going to be in a cold, wet environment for a long stretch of time, take precautions. Always pack an extra pair of socks and make sure your shoes fit properly. With preparation, trench foot shouldn’t be a condition you have to worry about.
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