Cold-weather warfare
Trench foot is a medical condition caused by prolonged exposure of the feet to damp, unsanitary, and cold conditions at temperatures as warm as for as few as 13 hours. Exposure to these environmental conditions causes deterioration and destruction of the capillaries and leads to morbidity of the surrounding flesh. Affected feet may become numb, affected by erythema (turning red) or cyanosis (turning blue) as a result of poor blood supply, and may begin emanating a decaying odour if the early stages of necrosis (tissue death) set in. As the condition worsens, feet may also begin to swell. Advanced trench foot often involves blisters and open sores, which lead to fungal infections. If left untreated, trench foot usually results in gangrene, which may require amputation. If trench foot is treated properly, complete recovery is normal, though it is marked by severe short-term pain when feeling returns. Trench foot affected tens of thousands of soldiers engaged in trench warfare in World War I. Keeping feet warm and dry, or at least changing into warm and dry replacement footgear, is the best way to avoid trench foot.
Children's feet
Contemporary management of the paediatric flat foot is directed according to pain, age, and flexibility, considering gender, weight, and joint hypermobility. When foot orthoses are indicated, inexpensive generic appliances will usually suffice. The paediatric flat foot proforma (p-FFP) directs this evidence-based approach. Three randomized controlled trials (RCTs) and one quasi-RCT have investigated the use of foot orthoses in children. The Cochrane Library systematic review analyzing the studies could not make a single recommendation, concluding that customised foot orthoses should be reserved for children with foot pain and arthritis, for unusual morphology, or unresponsive cases. There is an identified need for further research in this area. Surgery is rarely indicated for paediatric flat foot (unless rigid) and only at the failure of thorough conservative management.