The term arthroplasty refers to joint replacement through open surgery, which is used for cases where the joint has lost its function and the patient no longer has the ability to perform daily activities in the joint. In patients with knee osteoarthritis (arthrosis), the concentration of hyaluronic acid in the synovial fluid is lower than the normal value. As a result, by injecting hyaluronic acid (viscosupplementation), the patient's knee pain is reduced and the patient can carry out his daily activities as before. The pain reduction effect of hyaluronic acid injection usually lasts for 3 to 9 months, and after this period, the injection can be repeated up to 2 times. At this time, the surgeon can replace the joint by considering the patient's physical conditions as well as his age and activities. Joint replacement or arthroplasty is one of the methods considered to treat patients with advanced arthritis. Complications after arthroplasty are things that can be reduced by specialized physiotherapy. Many patients will gain appropriate abilities after surgery and recovery in physiotherapy clinics in such a way that they will return to normal conditions in daily activities, but some of them may need to extend the sessions or at least reduce the pain after surgery in different ways. The useful life of the joints depends on their conditions and how their use is different in different people and mainly the joints that bear more weight or those joints that are used more are more exposed to joint damage and destruction such as arthritis. Also, diseases such as rheumatic diseases, metabolic disorders can lead to the destruction of joints and the need for joint replacement. Most of the involved joints include hip and knee, and the incidence of involvement of these two joints is much higher than other joints.