Onychauxis is a mild medical condition in which the nail beds on, most commonly, toes thickens drastically causing the toenail to appear thick and hard.
by a docter,
Onychomycosis is a fungal infection of the toenails or fingernails caused by 3 types of fungi, called dermatophytes, yeasts, and nondermatophyte molds. The causes of Onychomycosis include wearing sweaty trainers or often having hot, sweaty feet. Fungi grow easily in warm, damp environments.