[Mechanical nail pathology]

Nails are submitted to a lot of trauma in the everyday life; their response to these traumatisms is various and they show themselves in misleading clinical manifestations leading often to misdiagnosis such onychomycosis or nail pathology of another origin. As for toenails dystrophies, repeated microtraumatisms in the shoes are the main cause and these dystrophies often reveal biomechanical disorders. As for fingernails, except the occupational pathology which is not related in this paper, nails dystrophies are particularly self-inflicted due to an obsessional-compulsive disorder. We are describing here the different nails dystrophies of mechanical aetiology, the different original factors and their mechanisms, as well as signs leading to the diagnosis.