Knee replacement surgery involves removing damaged or arthritic knee joint cartilage and replacing it with an artificial joint composed of metal and polyethylene components. This operation typically replaces the lower joint surface of the thigh bone (femur) and the upper joint surface of the shin bone (tibia). In some cases, the kneecap (patella) may also be replaced. The prosthetic components are secured to the bone with a special medical cement. Patients are generally mobilized one day after surgery, and their stitches are removed within 15-20 days.