If the finger has had trauma such as contusion, smash, crush injury, etc., it needs to go to the orthopedic department to take X-rays to see if there is a fracture, use braking, elevation, and external fixation in a cast or brace if necessary. 3. Inflammation caused by infection, such as dactylitis or nail infection in a single finger, will show symptoms of swelling and pain. 4. rheumatoid arthritis or osteoarthritis, it needs to go to the hospital to take blood to check the rheumatic series for differential diagnosis.