One of the most common problems to affect the toenails is a condition known as onychomycosis which the technical name for a fungal infection. They generally come in two types with one being a more superficial onychomycosis which tends to be a white discolouration near the end of the nail and a more deeper onychomycosis with a yellowish discoloration that tends to be more to the base of the nail. The main risk factor for onychomycosis is the damp and dark environment inside the shoes which is conducive to a fungal infection developing
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Onychomycosis