Total knee replacement is one of the most common and successful types of orthopaedic surgery performed in the U.S. each year. Patients who receive this treatment generally obtain significant relief from chronic pain and stiffness associated with osteoarthritis (daily wear and tear), a degenerative condition such as rheumatoid arthritis, or arthritis resulting from a past traumatic injury. The procedure includes removing cartilage and a small portion of underlying bone at the bottom end of the femur and the top end of the tibia. Next, a prosthetic implant is positioned and secured in place of the removed cartilage and bone to form a new joint surface. The kneecap may also receive a new surface in the form of a plastic cap. Finally, a specially designed “spacer” is positioned between the new knee components to allow them to glide against each other. In most cases, patients will be prescribed physical therapy beginning on the day after their surgery, with some movement of the knee being encouraged on the same day as the surgery.