What is it?

Trench foot, also known as immersion foot syndrome, develops when feet are cold and wet for prolonged periods of time without the ability to warm or dry the skin. This can result in pain, swelling, and numbness in the feet. This condition received its name during the 1st World War as this became a serious problem for soldiers on the battlefield, contributing to tens of thousands of casualties.

Symptoms/Risks

Symptoms may include, but are not limited to, tingling, itching, swelling, pain, coldness, numbness, pain, prickliness, and blotchy skin. Blisters may form which eventually lead to skin and soft tissue dying and sloughing off. In severe cases, an untreated foot may involve the entire foot destroying not just the skin but the soft tissues and bones of the feet. Exposure to extreme cold may cause frostbite or gangrene to develop, which are both devastating conditions with lifelong consequences and potential disability if not treated immediately.

Sports Medicine Evaluation & Treatment

As the skin of the feet becomes macerated, the underlying tissues are exposed to potentially infectious organisms. Skin is the first line of defense and a protective barrier to bacteria, fungi, and parasites. However, when the skin is compromised, these organisms may infiltrate into the tissues deep to the skin and cause infections. If there is any concern for an infection, medical care should be sought out immediately as these infections may penetrate into the blood stream, leading to shock and death.

Your doctor should inspect the feet carefully. Typically the diagnosis of a skin infection can be made clinically; however, lab tests and cultures may be ordered to rule out infections within the blood stream. X-ray and/or MRI tests are also sometimes ordered if there is concern of infection deep to the skin or in the bone. Your doctor may prescribe oral antibiotics if necessary to treat a suspected infection. Some infections in the feet may require hospitalization. Frostbite and gangrene may also require hospitalization. Dead skin and tissues require debridement as they serve as a nidus for infection and continued inflammation.

Injury Prevention

Trench foot may be prevented by keeping feet dry. Wet shoes and wet socks should be exchanged for dry ones. Shoes should be well-fitted and not overly-tight. Keep feet clean and check for any developing foot wounds at least once daily. Remove socks and shoes whenever resting or sleeping to allow the feet to air-dry. Athletes who tend to sweat profusely may use an aluminum-containing antiperspirant on their feet to prophylactically reduce the risk of trench foot.

Return to Play

Athletes may return to play when the feet are fully healed, the skin is intact, and there are no signs or symptoms of infection. Returning to play too early may not allow the skin to resume its protective barrier for the body, leading to further irritation and potential for infection.

AMSSM Member Authors
Scott Marberry, MD and George Pujalte, MD

References
Fudge JR et al. Medical Evaluation for Exposure Extremes: Cold. Clin J Sport Med. Sept 2015;25(5):432-436.
“Trench foot or Immersion Foot.” Centers for Disease Control and Prevention. Last updated Jun 20, 2014. https://www.cdc.gov/disasters/trenchfoot.html
Atenstaedt, RL. Trench foot: the medical response in the First World War 1914–18. Wilderness & environmental medicine. 2006;17(4):282-289.
Schwartz RB, McManus JG, Swienton RE. Trench foot (immersion foot). Tactical Emergency Medicine. Lippincott, Williams & Williams. 2008: 80.