As temperatures drop in the fall and winter, many patients with knee pain experience increased symptoms. Because these symptoms occur mostly in middle-aged and elderly people, they are often aggravated by cold and chill, so they are commonly known as “old cold leg”, which is called osteoarthritis of the knee in modern medicine. It is common in middle-aged and elderly patients and has a serious impact on their quality of life due to its complexity, long course and difficulty in treatment. Here to remind, protect the knee joint, improve the quality of life. Osteoarthritis of the knee, also known as degenerative knee disease, is a chronic joint disease characterized by degeneration of articular cartilage, joint space narrowing, synovial inflammatory hyperplasia and osteophytes at the joint edges. The knee joint is the largest joint in the body and bears the weight of almost the whole body. With its heavy burden and many activities, the articular cartilage is easily worn and destroyed. The congenital developmental defects of the waist or lower limbs, such as congenital hip dislocation, or bone and joint injuries such as fractures and joint dislocation, or other diseases such as septic arthritis and rheumatoid, can cause the joint contact surface to be unsmooth and the line of negative gravity to change, which can lead to degenerative changes in the knee joint and result in osteoarthritis. In addition, factors such as cold and humidity act on the body and can easily cause local nerve, blood vessel and soft tissue dysfunction in the knee joint, thus aggravating the condition. According to traditional Chinese medicine, the kidney collects essence and bone, while the liver collects blood and tendons. In the elderly, the liver and kidneys are insufficient, the essence of blood deficiency, tendons and bones are damaged, wind, cold and dampness easily invade the body, blocking the meridians and flowing into the joints, resulting in poor circulation of qi and blood around the joints, which is painful. Second, the characteristics of “old cold leg” “old cold leg” is generally slow onset, the course of the disease is long, manifested as both sides or one side of the knee joint often hidden pain, aggravated by activity, rest after the improvement. When it is cloudy, raining or snowing, or when the climate becomes cold, the symptoms worsen, so it is a common feature of patients with “old cold leg” that they like warmth and fear cold. It has been described as being able to predict weather changes in advance as a weather forecast. During the acute pain attack, the patient’s joints are stiff, and there is a popping sound when moving, and the stiffness of the joints worsens after sitting for a long time, but improves slightly after moving, and the symptoms are obvious when going up and down stairs.