Onychomadesis is a periodic idiopathic shedding of the nails beginning at the proximal end, possibly caused by the temporary arrest of the function of the nail matrix.:784:660 One cause in children is hand, foot, and mouth disease. This generally resolves without complication. Onychomadesis is a periodic idiopathic shedding of the nails beginning at the proximal end, possibly caused by the temporary arrest of the function of the nail matrix.:784:660 One cause in children is hand, foot, and mouth disease. This generally resolves without complication.