If you have a sore thumb nail, you need to clarify whether there is redness or swelling around the nail of the thumb, which usually reflects the condition around the nail. If there is an ingrown nail, where the edge of the thumb is bent into the skin and there is pressure or a broken condition, this can lead to nail pain. In addition, fungal or bacterial nail infections are not ruled out, as in the case of a finger barb, which, if torn off, can cause damage to the skin under the barb, leading to inflammation from bacteria entering the wound and causing pain. Therefore, if a barb appears, use a nail clipper to cut it off and avoid tearing it, as this can easily lead to nail fungus. Fungal infection of the nail is known as gray nail, and fungal infection of the skin around the nail results in fungal-caused onychomycosis. When both of these conditions occur, you need to visit a hospital where a doctor can clearly diagnose and prescribe the appropriate medication that can effectively treat the painful nail symptoms.