Total knee replacement (TKR) is a surgical procedure in which the arthritic or damaged surfaces of the joint are removed and replaced with an artificial joint called a prosthesis. The artificial joint is designed to move just like a healthy human joint.
During a total knee replacement surgery, the damaged bone of the lower thighbone (femur) is removed and replaced with the femoral part of the artificial joint. The tibial component replaces the upper surface of the shinbone (tibia). The patellar component (kneecap) replaces the inner surface of the kneecap (patella). Today, the parts of most knee implants are made of cobalt/chromium-(vitallium)-based alloys or titanium. A piece of specially designed plastic lines your kneecap and the top of the tibia component; this plastic acts as your new cartilage. A knee replacement is most often held in place by special bone cement that attaches the metal to the bone. The most commonly used bone cement is an acrylic called polymethylmethacrylate.
Your knee replacement surgeon will make a vertical incision on your knee. The length of the incision may vary. Generally, if using minimally invasive techniques, it may be four to six inches long and closed with temporary metal staples.
One size does not fit all during total knee replacement surgery. Knee implants come in different sizes to accommodate various body sizes, types and needs. Several manufacturers make joint implants. Your knee replacement surgeon will select the implant that best fits your needs. The weight of the prosthesis will be more than the weight of the bone that is removed. The weight will vary according to your size, but in general may weigh one to two pounds. You will not notice the weight in your knee.