In a total knee replacement, a specialist removes a damaged or deteriorated knee joint (the end of the bone where two bones connect). This joint is replaced with artificial parts called prostheses. These are made of metal and polyethylene, a metal-strength plastic. The artificial joint is fastened to the remaining bone using medical cement; in some cases the procedure is done without cement so that body tissues can grow into the prostheses.
The doctor operates through a small incision on the kneecap, from 3 or 4 inches above the knee to several inches below it. The artificial joint is held in place by the surrounding ligaments and muscles, just like your natural knee.
If you’re considering knee replacement surgery, we’ll first conduct an evaluation to determine if surgery is right for you. It begins with a detailed questionnaire about your medical history. This helps the orthopedic surgeon understand your pain, your physical limitations, and the progression of your knee problem. Next the surgeon examines you, measuring the range of motion of your knee, checking for bowlegs or knock-knees, and analyzing your muscle strength. A technician then X-rays your knee to help the surgeon plan the surgery and fit the prostheses. A small amount of fluid may be taken from your knee joint to check for infection. After the evaluation, the surgeon will discuss with you all of the possible options for treatment.
Most patients stay in the hospital just three or four days following knee replacement surgery. Physical therapy begins the day after surgery. When you can get in and out of bed without help and are able to walk safely with a walker and climb stairs, you can leave the hospital. Regular therapy sessions will continue for several weeks after you return home.
Full recovery typically takes three to six months. Within three to four months, you may be able to begin low-impact aerobic activities such as brisk walking, bicycling, and swimming.