Common causes of empty nails separated from the flesh include onychomycosis, nail dystrophy, and onychomycosis. 1. ringworm of the nail: this disease is caused by dermatophyte infection, in which nail trauma will increase the risk of this disease, diabetic patients and immunocompromised people are prone to disease. Nail color change, soft and brittle texture and thickness increase, with the progress of the disease may appear nail plate and nail bed separation and other symptoms. 2. Nail dystrophy: The causes of this disease are many, such as congenital ectodermal dysplasia, heredity, and psoriasis, lichen planus, eczema and other skin diseases, etc., which can lead to nail dystrophy, appearing as roughness of nails, nail separation, longitudinal cracks, transverse grooves, atrophy, loss of luster of the nail plate, and may also have symptoms of soft nails, thick nails, hooked nails and so on. 3. Nail separation syndrome: this disease can be caused by certain drugs, such as tetracycline, psoralen, fluoroquinolones, disease factors, such as psoriasis, and long-term contact with soap, nail polish and other chemicals. The first in the thumb, show finger, nail front edge of the nail plate and nail bed separation, there is a gap in the middle, easy to hide dirt, the surface looks dirty, and is not easy to remove and so on. It is recommended that patients combine their own situation, if necessary, to the regular hospital dermatology consultation, follow the doctor’s instructions to clarify the diagnosis, standardized treatment.