If you're a hiker, your feet are going to take a beating whatever measures you take to protect them—such is the nature of the hobby. However, while the occasional wound, blister and muscle strain is practically inevitable, there are other, serious conditions that can affect your feet on a lengthy hike, conditions you should take care to prevent however you can. One of the most dreaded is sometimes referred to as immersion foot, but you will probably know it as trench foot.

What is trench foot and what causes it?

Trench foot is essentially a prolonged loss of blood circulation to the skin of the feet. This leads to an inflammation of the epidermal tissues of the foot that causes your feet to swell dramatically and become discoloured. Other symptoms will generally include permanently cold feet, localised pain or numbness, cracking and bleeding of the skin and tingling. In extreme cases that have been left untreated for long periods, the skin of the affected feet may die and become necrotic, leading to gangrene and the possibility of amputation.

Trench foot is caused by constantly wet and cold feet, and takes its name from the cold and wet conditions of the World War One trenches in which it thrived. Unlike frostbite, trench foot does not require sub-zero temperatures to occur, and can afflict somebody hiking in relatively temperate conditions. For hikers, this water damage is exacerbated by the constant, undetectably small amounts of damage done by every step of a hike - this damage creates small wounds which exacerbate swelling and pain, and may lead to fungal infection.

How can I prevent trench foot happening to me?

1. Keep your feet dry as much as possible. Hikers should carry several pairs of spare socks with them at all times, so they can switch them out when they become soaked. Even if your socks remain relatively dry, you should take them off for brief periods along your walk, to allow the accumulation of sweat to dry out. Wear socks appropriate to the weather conditions to avoid excessive foot sweat, but do not wear socks that are so thin and breathable that they do not provide adequate protection against shoe rubbing.

2. Choose a well-fitting hiking boot or shoe. They should allow moisture, sweat and rainwater to evaporate away easily through breathable panels. Only wear heavy, enclosed hiking footwear if you know you will be hiking through boggy conditions or in considerable cold. Invest in breathable, well cushioned insoles too. Consult a podiatrist to have custom-fitted insoles created for your feet, as these will be more comfortable to walk on if you feet begin to swell.

3. Keep your feet uncovered while you sleep. That is, unless conditions are so cold that you risk frostbite or hypothermia by doing so. In cold conditions, wear a clean, dry pair of socks at night.

4. If your footwear becomes soaked during the day, switch to a spare pair for the next day. You can also make every effort to dry them out overnight. If this is not possible, wear waterproof socks until your shoes are dry, or improvise them with plastic bags or strips of tarpaulin.

5. Clean your feet regularly to clear away grime that holds moisture against the skin. This also reduces the risk of fungal infection.

6. If you notice that your feet have developed the first signs of trench foot, your hike is over. Further walking will only cause more damage. Seek medical attention as soon as possible. A doctor will provide warm compresses to restore blood circulation and reduce swelling, and treat any open sores, cracks or signs of infection that may have developed. You may also be prescribed painkillers and/or antibiotics.

If more treatment is required for an advanced case of trench foot, you may require minor surgery to remove skin tissue that cannot be saved. Only in the most extreme cases of gangrene will amputation be considered. Learn more about your options and how to keep safe while hiking by contacting clinics such as Tim Pain Podiatry.