Total Knee Reconstruction

The following information is for patients who have arthritis in one, or both, knees causing them such pain that they can no longer carry out their normal activities. The primary aim of a total knee replacement operation is to relieve this pain. It may, in addition, increase the joint’s motion and correct deformity.

On this page you can find answers to the following questions:

Do I need a total knee replacement?

When the pain caused by arthritis in your knee joints becomes so great that daily activities are no longer possible, a total knee replacement should be considered. This page will inform you of the nature of the operation and what to expect. It designed to help you decide whether or not you would like to undergo the surgery. 

What does the procedure involve?

A general physician will evaluate your condition prior to admission to the hospital. It is important that we ensure that you are healthy enough for surgery. The specialist will follow up throughout the process to keep a check on your general medical condition.

Usually, you will be admitted to hospital on the day of your surgery. The anaesthetist will discuss with you the type of anaesthetic that will be used—depending on your medical condition, this could be a general, spinal or epidural anaesthetic. In the case of an epidural, you will not be fully asleep. Anaesthetics may be used post-operatively to help manage your pain.

The first step in the surgery is to make a long incision in the front of your knee, exposing the arthritic joint surface. The arthritic surface is removed through a series of small, precise cuts that allows a metal cap to fit neatly over the end of the thigh bone (femur), and a metal-backed plastic component can be placed over the end of your shin bone (tibia). The back of the kneecap may undergo a similar cleaning, and replaced.

These components can be bonded to the bone, using bone cement, or an implant with a porous backing may be used. In this case, the bone grows into the implant and secures it. Each method has its own advantages and disadvantages—your age, weight, bone quality and other factors will determine which is used.

The procedure requires around two hours, however several hours will be spent in preparation and in the recovery room.

How long will I spend in hospital?

You can expect to be home about one week after surgery.

How long will it take to recover? What can I expect?

A total knee replacement is a major operation. You should expect to experience a high degree of pain in the post-operative period. The pain can be managed through an epidural, or a patient-controlled anaesthesia machine. This machine allows you to administer your own pain relief, as you feel you need it. You will feel well enough to simply take pain medication after one to three days.

Pain tolerance differs from person to person. Some patients have experienced very little pain in the post-operative period, others have commented on how badly prepared they were for the pain they experienced. There will be a great deal of pain, of course, but in most cases it is managed successfully by the methods outlined above.

Your recovery should begin within a day or two after surgery, by which time you will be able to sit in a chair. You will be able to walk with a walker or crutches within one to five days. Excess blood will be drained away from your knee using tubes and these can be removed within the first day after surgery.

While in hospital you will undergo rehabilitation and physiotherapy and this will continue after discharge to regain motion and strength in your knee. You will redevelop the ability to straighten out, flex and bend your knee. While in hospital, a machine may be used to aid you. You will be able to swim within two weeks of the surgery.

Walking, golfing and biking can be resumed after two to three months, although running and jumping are discouraged. Avoid sports that require you to do either. Your recovery to full strength is expected to take up to six months.

Once your recovery is completed without complication, you can expect to have a knee that hurts much less and functions better than prior to surgery. It will not be perfect, however, and at times you will experience aches and pains, clicks and pops. Prior to surgery you may have had extremely limited motion. At the very least you will regain this motion if not experience some improvement.

What are the complications?

Following a total knee replacement, it may be difficult to bend the knee back more than 90°. The early stages of rehabilitation and physiotherapy, while you are in hospital and during the first month after your discharge, are very important. In the event that you cannot bend the knee through a full 90°, you will have trouble on stairs, getting in and out of cars, getting dressed and putting on shoes. In this case, further manipulation may help.

Infection affects 1—2 % of total knee replacement patients, making it a relatively rare complication. It is, however, a major one. Pus or festering may occur in the knee while you are in hospital or in the immediate post-operative period. An infection may even develop months or years later. In this event, further surgery—or series of surgeries—will be required to clean out the knee. The components have to be removed and often cannot be replaced. Organisms that are sensitive to antibiotics can be successfully treated and an attempt to replace the components can be made about six weeks after their removal. If this is unsuccessful (because the component replacement is impossible, or the infection recurs) the knee has to be fused into a straight position. This complication is extremely serious and, in its worst form, could lead to the loss of the limb and, possibly, life.

Other complications include the loosening, or failure, of the components. In this case, surgery will be required to replace them. The plastic part of the components does wear and, depending on your weight and level of activity, may need replacement.

Blood clots, or phlebitis, may form in the leg or the deep veins of the pelvis and will require treatment with a blood thinner. Should the clot become loose, and travel to the lung, it can be life-threatening. Everything possible will be done to avoid this complication. The application of alternating compression devices on both legs, and the use of aspirin, will help to prevent clotting.

There may be excessive blood loss, requiring a blood transfusion. There is a small risk of contracting AIDS or hepatitis from a blood transfusion. We encourage our patients to donate their own blood or, if they have the right type, have their families donate for them. A machine will collect some of the blood lost during and after the surgery, and this can be returned to you reducing the need for a transfusion. While nerve and blood vessel damage can occur, it is quite rare, although severely deformed knees are more likely to have this complication.
Be assured that we will do everything we can to reduce the risk of complication and to ease your pain.

How long will the implant last?

It is difficult to predict with any degree of certainty how long the implant will last. Modern implants last much longer than they did 10-15 years ago. An implant will wear quickly if:

  • You are young and active
  • You are overweight
  • You engage in work that requires you to be on your feet
  • You run, jump or walk excessively.

Patients over the age of 65, who are of a normal weight and do not place too many demands on the implant, can expect to have it for the rest of their lives. A patient in middle age, however, who is overweight and places high demands on the implant may find that it fails within 5-10 years of surgery.

NB: If you require dental work or surgery on your stomach, intestine or gallbladder, it is important that you take prophylactic antibiotics. Should you fall ill with a fever, be sure to inform your doctor that you have had a total knee replacement.