In 1995, James Campbell, president of the American Pain Society, proposed that pain should be listed as the “fifth vital sign” after blood pressure, respiration, pulse, and temperature, and in 2002, experts at the 10th IASP Congress agreed that chronic pain is a disease. Pain is the most common human suffering and one of the most unbearable symptoms for patients, and surveys in the United States, Canada and China show that chronic pain is a very common phenomenon. The results of a survey of chronic pain in six cities in China completed in 2003 showed that orthopedic conditions caused 64% of chronic pain. Chronic pain is not only about the pain itself, but more importantly, long-term pain stimulation can contribute to the pathological remodeling of the central nervous system, making the progression of the disease more difficult to control. Early pain control can slow down the development of this process. In addition, chronic pain is more than just a painful sensory experience. Research studies have shown that chronic pain can severely affect somatic and social functioning, preventing patients from participating in normal life and social activities.