Is it possible to delay the loosening of the joint or increase the longevity of the implant?
Yes. Longevity of the implanted knee joint can be increased in many ways. The first and foremost is to maintain ideal body weight. In many patients, their total knee replacement will last their lifetime and in others, it may not. Total knee replacements are designed to provide painless and unlimited standing, sitting, walking, and other activities of normal daily living. They do very well for walking, bicycling and swimming. They are not designed for jogging or sports like tennis and skiing. You should be aware that the longevity of a total knee replacement may be shortened by frequent, vigorous activities.
How would I know if I need a Revision Knee Replacement?
Usually a well functioning knee replacement would last for at least 12-15 years. During this time, you would have no pain and would walk without any pain or discomfort. The first sign of loosening could be pain or swelling in the knee joint or a feeling of instability. If you get any such problem in a previously asymptomatic knee, you must visit your orthopaedic surgeon for examination who would usually get an x-ray of your operated knee to make sure that there is no evidence of loosening of the joint or malposition of joint implants.
What procedures and tests are carried out before Revision Knee Replacement?
Once the decision is made to do the revision operation, standard assessments are performed, including x-rays, laboratory tests, and possibly other investigations like bone scans, CT scans or Magnetic Resonance Imaging (MRI) studies. X-rays may demonstrate a change in the position of components and damage to the underlying bone. It is also necessary to do certain tests to make sure that there is no infection in the knee joint. For this, certain blood tests are carried out and fluid is aspirated from the knee joint and is tested for any infection. If the blood tests and the fluid aspirated from the joint confirm absence of infection, the surgeon would decide to go ahead with the revision operation.
What happens during the operation?
Most revision total knee replacements take longer to perform than the primary procedures. In the first step, the implants are removed. If there is significant bone loss, bone grafting is required which can be either an allograft (bone tissue from another person obtained from a bone bank) or autograft (your own bone taken from another site of your body) to fill the defects in the bone. In some cases, metal wedges, sleeves and stems may be used along with the knee implants to achieve solid fixation of the newly implanted joint. Drains are usually placed to prevent collection of fluid or blood in the joint after surgery.
What is the after care?
Post-operative care after revision knee replacement is similar to the care after a primary knee replacement. This includes a combination of pain management, physical therapy and measures to prevent blood clot formation. A brace or splint may be used to protect the joint after the surgery. In some cases, it may be necessary to allow only protected knee weight bearing like partial weight bearing or toe touch weight bearing to allow bony healing. Devices such as a walker or a stick are used in the early postoperative period.