Artificial joint replacement refers to the use of metal, polymer polyethylene, ceramic and other materials to make artificial joint prosthesis according to the form, structure and function of human joints, which is surgically implanted into the human body to replace the function of the diseased joint, in order to relieve joint pain and restore joint function. One of the most successful orthopaedic surgeries of the 20th century, artificial joint replacement has allowed countless patients with end-stage bone and joint disease to resume a normal life, and in a 2007 review article published in the Lancet, the leading medical journal, even called artificial hip replacement “the surgery of the century”. Although there are no accurate statistics, conservative estimates suggest that more than 1.5 million people worldwide receive artificial joint replacements each year. With an aging population, increasing average life expectancy and improving quality of life, the demand for arthroplasty continues to grow. This demand is even more pronounced in China. Currently, knee and hip replacements are two of the most common types of artificial joint replacements, with a success rate of more than 90% over 10 years, and more than 80% of patients are able to use the implanted prosthesis for more than 20 years, even for the rest of their lives. In addition to these, joint replacements of the shoulder, elbow, and ankle joints are also evolving, with good medium- and long-term results. With the advancement of biomaterials and surgical techniques, small joint replacements such as wrist, interphalangeal and metatarsophalangeal joints have emerged one after another, bringing hope to patients suffering from serious small joint diseases. What diseases are suitable for artificial joint replacement Indications for artificial joint replacement include severe degenerative osteoarthropathy, rheumatoid arthritis, traumatic arthritis, ankylosing spondylitis, congenital developmental malformations resulting in arthritis or joint pain and dysfunctional movement, Paget’s disease, and tumors of the bone and joint. What is the best indication for arthroplasty when the disease has progressed? Pain that cannot be controlled by conservative treatment In the case of degenerative osteoarthropathy, for example, after the initial onset of pain and other discomfort, the patient should first achieve relief of joint pain by adjusting daily work habits, reducing activities, avoiding excessive weight bearing on the joints, and paying attention to rest. When the pain cannot be controlled, oral non-steroidal anti-inflammatory drugs and physiotherapy should be administered to relieve the pain, and sodium glacial injection into the joint cavity is also feasible. When these conservative treatments fail to improve pain symptoms, joint replacement surgery may be considered. Prognosis The main purpose of arthroplasty is to relieve joint pain, correct joint deformity, restore joint function, and improve the patient’s quality of life. Every patient who will have an artificial joint replacement is concerned about “how many years will the artificial joint last?” This is also known as the life expectancy of the artificial joint. As an organ replacement, artificial joints are subject to wear and tear and failure, but modern artificial joint prostheses have achieved good long-term survival rates. The National Institutes of Health (NHS) in the United Kingdom has proposed a standard for artificial joint replacement that has a success rate of at least 90 percent over ten years, called the NICE standard. In clinical practice, there has been a lot of data showing that through good surgical techniques, selection of suitable artificial joint prosthesis, and with full cooperation of patients, the 20-year excellent rate of artificial joint replacement, especially knee and hip replacement, can reach more than 90%. With the improvement of prosthesis design and materials, surgical techniques and rehabilitation measures, it is reasonable to believe that artificial joint replacement will achieve even better results. Complications (1) Loosening of artificial joint prosthesis (2) Dislocation of artificial joint prosthesis (3) Fracture of artificial joint prosthesis (4) Deep vein thrombosis and pulmonary embolism (5) Periprosthetic infection (6) Postoperative nerve and blood vessel injury and periprosthetic fracture (7) Joint instability and stiffness after artificial joint replacement (8) Postoperative pain after artificial joint replacement