Older people are becoming more and more numerous and older in China. However, elderly people often lack self-care awareness and do not take active and effective treatment for early aging knee lesions. It is only after severe swelling and pain and deformity of the joints that they think of seeking medical attention, and after X-ray radiographs, doctors diagnose advanced (severe) osteoarthritis, where medication and injections are very ineffective, and patients are mostly advised to be hospitalized for knee replacement surgery. When older people hear about knee replacement, they are afraid, but their fear is due to a lack of understanding of the surgery. Modern orthopedic surgery techniques are developing rapidly, and knee replacement, a mature orthopedic surgery, was introduced to China in the 1980s and is now a routine procedure that is flourishing and developing rapidly. The so-called knee replacement is a knee surface replacement technique that removes the hyperplastic and necrotic tissue from the joint surface, preserves the normal osteochondral tissue, and covers the joint surface with an alloy material, spaced by a polyethylene liner, to correct the inversion and flexion contracture deformity of the affected knee. The introduction of modern minimally invasive surgery has resulted in smaller incisions for knee surface replacement, better aesthetics, and less damage to muscle and bone tissue. The average smooth and skilled operation takes about 1 hour. On the first day after surgery, the surgeon will instruct the patient to perform functional training of the joints and muscles in bed, and he or she will be able to walk adaptively on the ground 3 days after surgery and resume normal life and work about 1 month after surgery. The implant material used in knee replacement surgery generally lasts about 20 years, which is longer and more durable than the artificial hip material and is better adapted to the daily needs of the elderly.