How to recognize and treat trench foot — the deadly condition that claimed thousands of lives in WWI

• Trench foot is a painful condition that occurs when you stand in cold water for long periods of time.
• It comes in four stages: injury, immediate post-injury, hyperaemic phase, and post-hyperaemic phase.
• Those at risk of trench foot are mostly in the military, agriculture, or are homeless.

Trench foot is a condition that occurs when your feet are in a cold, wet (and sometimes unsanitary) environment for a prolonged period. It commonly affects the heels and toes, but it can also reach the knee.

The term was first described in 1812 by a French army surgeon, but trench foot is most known for running rampant during World War I, when soldiers stood in cold, waterlogged trenches for extended periods. It's estimated that trench foot contributed to the deaths of 75,000 British and 2,000 American soldiers.

Therefore, trench foot can be a very serious condition, but it's also easily treated. Here's more on the stages, causes, treatment, and prevention of trench foot, so you hopefully never get it.

Stages of trench foot

According to David S. Fine, DPM, podiatrist at AdventHealth North Pinellas, the condition goes through the following stages:

• Stage 1 — injury: There is a reduction or loss of blood flow to the affected area, causing a tingling feeling that eventually leads to numbness. The limb may appear red or white.
• Stage 2 — immediate post-injury: Swelling and an odor of decay can occur. The limb may turn from white to blue when it is warmed, but remain feeling cold and numb.
• Stage 3 — hyperaemic phase: Patients may experience pain and develop blisters or sores, which puts them at risk for fungal and bacterial infections. The limb becomes hot and red.
• Stage 4 — post-hyperaemic phase: Persistent nerve damage arises. Most patients will experience long-term sensitivity to cold conditions that can last a lifetime.

If gangrene develops — a condition where body tissue dies because of a serious bacterial infection or lack of blood supply — amputation may be required to avoid the disease from progressing any further, preventing sepsis and even death.

Causes of trench foot

Trench foot is caused by having your feet in cold and wet conditions, says Sean Peden, MD, Yale Medicine orthopaedic foot and ankle surgeon and assistant professor at Yale School of Medicine. The disease can develop when exposed to temperatures between 33 °F to 60 °F for 10 to 14 hours.

The cold temperature constricts blood flow to prevent heat loss because wet feet lose heat 25 times faster. As a result of the lack of oxygen supply, skin tissue gets damaged.

"This is generally not an issue for the majority of us," says Peden. The people most at risk for trench foot are homeless individuals, military officers, agricultural workers, Peden and Fine say.

How to treat trench foot

If you think you have trench foot, you need to seek medical attention immediately.

Although you may be able to treat the immediate effects of trench foot with the following, you still need individualized medical care:

• Remove the feet from the cold, wet environment that caused the condition.
• Clean and dry the feet thoroughly.
• Warm the affected area with warm packs or by soaking in warm water (102 °F to 110 °F) for about five minutes.

"Oral antibiotics and topicals can be used to treat sores, wounds, and other critical problems that can arise from trench foot. The typical treatment varies based on the severity of the patient's stage with trench foot. The more acute to chronic usually requires one to three weeks of treatment," says Fine.

There might be temporary pain when sensation returns to the affected area, but as long as the condition was identified and treated early, you can have a complete recovery.

How to prevent trench foot

To avoid developing trench foot, you must do the following:

• Wear appropriate footwear for the activity.
• Keep your feet clean and dry.
• Change socks and shoes whenever they get wet.
• Check the condition of your feet at least once a day.
• Don't sleep with socks on to allow the air to dry the feet and avoid sweating.
• Elevate bare feet when sleeping to reduce any swelling.

Insider's takeaway

You may be at risk for trench foot if your feet are often in cold and wet environments for long periods. It's important that you clean and dry your feet thoroughly and change socks and shoes whenever necessary to prevent developing the condition.

If you think you have trench foot, seek immediate medical attention.

Trench foot does not discriminate, and we've seen patients as young as 15 years old develop it, says Fine.