Total knee joint replacement
Total knee joint replacement (TKJR), also called Total Knee Arthroplasty, is a procedure where an artificial surface is used to replace the worn or damaged weight bearing surfaces of the knee joint. The primary aim of the procedure is pain relief and to return an individual to pain free activities of daily living. The most common reason for a Total Knee Joint Replacement is osteoarthritis of the knee joint.
An incision is made over the front of the patella (knee cap) and the patella is retracted out of the way in order to expose the knee joint. The ends of the femur (thigh bone) and tibia (shin bone) are removed to remove the damaged surfaces of the joint. The prosthesis (implant) is then implanted and fixed to the ends of the bones using bone cement. The implants are generally made from a combination of metal and polyethylene plastic, however a variety of new materials such as ceramic are being used.
The surgery is usually performed under general anesthesia, but can also be performed with a spinal or epidural anaesthetic. Often a combination technique is used in order to provide better pain relief.
The surgery usually takes between one to three hours, and you will usually stay in hospital for about five days.
After your surgery
Initially after the surgery you will have a large dressing over the knee, and will likely have one or two plastic drainage tubes coming from within the knee. The drainage tubes will usually be removed the day after the surgery. Analgesia (pain relief) will be given to you from the time of surgery, and can come in a variety of forms from tablets through to an epidural catheter or a patient controlled analgesia (PCA) pump.
Movement of the knee joint often begins as early as the day after the operation. Occasionally a machine called a continuous passive motion (CPM) device is used to assist bending (flexing) and straightening (extending) of the knee. The specific post-operative regime will be managed by your orthopaedic surgeon.
You will leave hospital when you are mobilising safely with crutches and will remain using crutches for up to six weeks. Your surgeon will follow you up post-operatively, commonly at the six week mark and then at regular intervals over the first two years.
The majority of the pain will have resolved at the six week mark, but may persist for up to twelve weeks in some cases. You may be able to return to activities such as driving or golf as early as the six to twelve week stage depending on your progress.
The long term outcome
A knee joint replacement typically lasts for at least ten years, and many last for much longer. Occasionally there are complications such as the replacement loosening or wearing out early, and in these cases a revision procedure may be needed.
The vast majority of patients will have a straightforward surgical procedure and recovery course, with an outcome of a pain free and functional knee joint.
A knee joint replacement is a major surgical procedure which includes small but significant risks. These include the possibility of blood clots or deep venous thrombosis (DVT) of the veins of the legs or pelvis, bleeding, post-operative infection, joint stiffness, or implant loosening or failure. There are other risks associated to this procedure, and it is important that you have a thorough conversation with your surgeon about the possible complications prior to surgery.
Pre-existing medical conditions can alter the level of risk associated with any procedure, and it is important that you notify your surgeon and anaesthetist of any medical problems prior to surgery. It is also important to follow your surgeon's instructions both before, and after, surgery to ensure that these risks are minimised
The components that determine the cost of the procedure are the surgical theatre costs, hospital costs, implant costs, anaesthetic fee and the surgeon's fee. Prices vary and may depend on; the extent/complexity of the procedure, the physical attributes of individual patients, and the surgeon performing the operation. A Total Knee Joint Replacement typically costs around $25-30k.