Separation of the nail from the nail bed, medically known as onycholysis, is a common condition that results in a white appearance of the affected part of the nail. Fingernail or toenail separation can have numerous causes but is typically related to trauma or a fungal infection of the nails. Nail separation can sometimes be associated with other abnormalities of the nails, including nail pitting, flaking or crumbling, or other damage to or changes in the nail. Toenail or fingernail separation is generally painless and may occur gradually, without the affected individual being aware of a distinct cause. In some instances, onycholysis can be related to systemic conditions, including connective tissue disorders or hyperthyroidism.

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