After knee replacement surgery, pain is mainly divided into two stages: the first stage is the post-operative wound pain, which is usually relieved significantly about 2 days after surgery. The second stage is the pain during the functional recovery exercise, which may last 1-2 months repeatedly and will be relieved only after the local ligaments and soft tissues have been repaired for a period of time and the local activities have gradually become flexible. For obvious pain after knee replacement, strong painkillers can be given to relieve pain, such as tramadol or oral rophenadrine extended-release tablets. For chronic pain formed by late functional exercise you can choose creams, such as flurbiprofen baboo, in addition to hot compresses and massage, and also apply drugs such as fotarine. In case of long-term pain, X-rays need to be reviewed to see if there is any loosening of the prosthesis, or if there is local infection or other factors causing persistent pain.