The pain and swelling next to the nail may be caused by trauma, onychomycosis, purulent dactylitis and so on. 1. Trauma: when the finger area suffers from external impact, contact with chemical products and other traumatic injuries, local tissue stimulation or damage will appear next to the nail pain and swelling phenomenon. 2. Inguinitis: Inguinitis is caused by pathogenic bacterial infection, which can be induced by damage to the tissues around the nails and long-term repeated exposure to certain irritating factors. Patients with inguinitis are mainly manifested as redness, swelling, heat and pain in the periungual tissues, and in severe cases, the periungual tissues will become pus. 3. Purulent dactylitis: Purulent dactylitis is mostly caused by finger puncture wounds, and the common causative organisms are staphylococcus aureus and streptococcus. Purulent dactylitis will cause the patient’s fingertips have needle-like pain, tissue swelling symptoms, some serious cases may appear broken pus, tissue necrosis and other symptoms. It is recommended that people with painful and swollen fingernails should seek medical attention to determine the cause of the condition and follow the doctor’s instructions. Pay attention to the care of the end of the finger, to avoid friction and stimulation of foreign objects or contact with chemical products.