An artificial joint is a medical device designed to replace a damaged or worn-out joint in the body, such as the knee or hip. These joints are typically made from materials like metal, plastic, or ceramic, and are surgically implanted to restore function and relieve pain. The procedure to install an artificial joint is known as joint replacement surgery. This surgery is often recommended for individuals suffering from conditions like arthritis or severe joint injuries. After the surgery, patients usually undergo rehabilitation to regain strength and mobility in the affected area.