Total knee replacement (sometimes shortened to TKR) is a surgical procedure to replace the ends of the femur and the tibia that have been damaged by osteoarthritis or other conditions, with prosthetic devices that duplicate the motion and weight-bearing abilities of the original joint. In Total knee replacement, the prosthesis is comprised of several parts.

The tibial component includes a metal base and a plastic insert. Together these replace the top of the tibia (shin bone) and the cartilage in the knee to provide half of the new joint's bearing surface.

The femoral component replaces the bottom of the femur (the thigh bone). This component also replaces the groove in the natural knee where the patella or kneecap rides.

The patellar component replaces the surface of the knee cap, which rubs against the femur. The patella protects the joint, and the resurfaced patellar button will slide smoothly on the front of the joint. In some cases, surgeons do not resurface the patella.

Who Needs It

Your surgeon's recommendation for knee replacement is based mainly on your level of pain and disability; there are no absolute restrictions on age or weight. Most of the people who have knee replacement surgery are between the ages of 50 and 80. The procedure has a high success rate and is considered relatively safe and effective. Women are more likely to undergo the procedure; in 2009, the rate of knee arthroplasty for female patients was 57 percent higher than for males.

There are several reasons why your doctor may recommend knee replacement surgery.

People who benefit from knee replacement surgery often have:

  • Knee pain that limits everyday activities, such as walking or bending
  • Knee pain that continues while resting, either day or night
  • Stiffness in a knee that limits the ability to move or bend the leg
  • Inadequate pain relief from anti-inflammatory drugs, physical therapy, or walking supports