Patients do not know much about artificial joints and often think that during surgery, the joint will be completely removed and fitted with a stainless steel joint, and that the limb will look like a robot after surgery, which is stiff and unnatural. In fact, artificial joint replacement only removes the worn and damaged joint surfaces and implants them like braces to restore a normal smooth joint surface. Artificial joint replacement is arguably one of the greatest breakthroughs in orthopaedic surgery in this century. It has been used in the treatment of the shoulder, elbow, and other joints. However, artificial hip and knee joints are the most common. The design and materials of artificial joints are the result of the continuous efforts of biomechanics experts, material engineers and orthopedic surgeons. Most of them are made of metal and high-density plastic materials that follow the structure, shape and function of the human joint. In order for the joint and bone to be tightly bonded and not easily loosened in the future, it can be fixed with bone cement or treated with different coatings on the artificial joint to allow the bone to grow in.