What are the risks and complications of total knee replacement surgery?

Risks and complications are a part of any surgical procedure, particularly the risk of unexpected reactions to anesthesia and potential excessive bleeding. There is also a 3 percent risk of infection after surgery. Often patients are administered antibiotics as a prophylactic measure to minimize this risk. However, should infection occur an implant might need to be removed and subsequently replaced.

The primary long-term complication specific to a total knee replacement is the eventual need to replace the implant in about 10 to 15 years. This is because the implant will wear out with use and over time, particularly if the patient is physically active. The lifespan of the implant can be extended through weight loss and the curtailing of high-impact activities like running and jumping. However, the implant will still deteriorate with the passage of time, especially if the patient is under 65.

While total knee replacement surgery has become routine and many hospitals have orthopedic surgeons who only perform this procedure, there still exists the possibility for complications. It is unfortunately not a rare occurrence for the alignment in a replacement knee to be set so that added wear and strain is placed on the implant. This can result in dislocation of the artificial joint and discomfort.

Another possible complication of this surgery involves the patella. The kneecap is moved aside during the procedure and when replaced, it may present unevenness in the tissue or instability. It may even direct touch the implant and this can cause discomfort.

Most joint failures can be attributed to the loosening of the implant from the bones. This can be a result of bone tissue that is deteriorating. The joint is protected by a synovial membrane (a thin layer of tissue) which provides lubrication to the joint and eliminates foreign matter. If the synovial membrane becomes inflamed it fills the joint with extra fluid. This excess liquid applies pressure and adds force when the joint is moved and causes the tissue to break down. Symptoms of synovitis include a knee that feels warm to the touch and puffiness.

It should be noted that only one out of every 50 total knee replacement patients suffer a serious complication.