In young people, the joint surface of the knee is very smooth and beautiful (shown in Figure ①), while in osteoarthritis of the knee, the joint surface is worn and damaged, accompanied by the proliferation of bone spurs around the joint. Long-term use of anti-inflammatory and analgesic drugs will have toxic side effects on vital organs such as the heart, kidneys and gastrointestinal tract. Studies have shown that osteoarthritis of the knee not only affects the patient’s quality of life but also shortens the patient’s life expectancy due to the chronic pain that leads to impaired motion and the toxic side effects of long-term medication. Knee replacement has been called the most successful surgery of the 20th century! Clinical experience at home and abroad has proven that knee replacement can effectively relieve pain, restore joint function, and significantly improve the quality of life of patients. Rather than replacing the entire joint, the procedure involves removing the worn bone surface and the enlarged bone spur, and then covering the fresh osteotomy surface with titanium alloy (as shown in Figure 3), which effectively relieves the pain caused by friction on the bone surface. At present, some large and medium-sized hospitals in China have already started the construction of pain-free wards for the perioperative period of knee replacement, which can effectively improve the comfort of patients during hospitalization, while the specialized rehabilitation team can also guide patients to carry out formal rehabilitation training to maximize the recovery of joint function and improve the quality of life within a short period of time.