A total knee replacement is an operation that removes the knee joint and replaces it with a new, artificial joint (prosthesis). The knee is a hinge-like joint, formed where the thigh bone (femur) and the shin bone (tibia) meet. The lining inside the knee is a soft cushion of cartilage. Over time, the cartilage can wear away. As it does, the knee becomes stiff and painful.
Total knee replacement does three things: replaces the worn-out cartilage with artificial cushioning, replaces the end of the femur with a metal surface, and replaces the tip of the tibia with a plastic piece and metal stem. In some cases, a plastic piece may be added to the back of the kneecap to create a smoother surface.
An estimated 90-95% of patients achieve good to excellent results with relief of discomfort, as well as an increase in both activity and mobility. Total knee replacement patients recover quickly and will likely be able to walk the first day after surgery.