Toe nail hollowing out may be caused by trauma, or may be caused by nail fungus, nail dystrophy and other diseases. 1. trauma: if the patient’s feet have been traumatized, it may cause the patient’s toe nails to appear the phenomenon of atrophy of the nail bed, which will lead to the patient’s toe nails hollowed out. 2. ringworm of the nail: ringworm of the nail is usually due to skin infection caused by dermatophytes, patients will appear nail plate turbidity, thickening, discoloration, atrophy and other symptoms. In addition, patients with onychomycosis will also have symptoms such as shedding, buckling and hooked nails. 3. Nail dystrophy: the causes of nail dystrophy include congenital and acquired, and the main symptoms of patients are thinning nails, turbidity, thickening, fragile, nail peeling, etc. In addition, patients with onychomycosis may also have symptoms such as shedding, buckling, hooked nails, and so on. In addition, patients with nail dystrophy will also appear nail surface loss of luster, roughness, transverse grooves and other symptoms. Patients with symptoms of hollow toe nails should go to the hospital in a timely manner to identify the specific causes of the disease, and follow the doctor’s instructions to take regular treatment measures to avoid aggravating the condition.