Swollen nails and found pus, consider the subnail infection, most commonly seen after trauma, especially local contusion, the formation of hematoma secondary infection. In this case, surgery should be chosen in time, under the anesthesia of the nerve block of the root of the finger, the routine disinfection of the operation area, spreading the towel, you can choose to partially excise the nail, and the pus will be drained out. Alternatively, local puncture, aspiration, and drainage of pus can be performed with a syringe, but it is incomplete and may result in localized residue. It is also necessary to carry out intravenous anti-infection treatment after the operation and insist on changing the medicine, because if the best time for treatment is delayed, the infection may be further aggravated, and even induce osteomyelitis, and in serious cases, finger amputation is needed, so the early diagnosis should be made in time to go to the hospital. During the treatment, you can elevate the limb, which can promote venous blood return and reduce the symptoms of swelling and pain.