Trench foot
The mainstay of treatment, like the treatment of gangrene, is surgical debridement, and often includes amputation. Self-treatment consists of changing socks two or three times a day and usage of plenty of talcum powder. Wherever possible, shoes and socks should be taken off, feet bathed for five minutes, patted dry, talcum powder applied and feet elevated to let air get to them.
Flat feet
An easy and traditional home diagnosis is the "wet footprint" test, performed by wetting the feet in water and then standing on a smooth, level surface such as smooth concrete or thin cardboard or heavy paper. Usually, the more the sole of the foot that makes contact (leaves a footprint), the flatter the foot. In more extreme cases, known as a kinked flatfoot, the entire inner edge of the footprint may actually bulge outward, where in a normal to high arch this part of the sole of the foot does not make contact with the ground at all.