Frequently Asked Questions
Osteoarthritis or Degenerative Joint Disease – the most common type of arthritis. Osteoarthritis is also known as wear and tear arthritis. Since the cartilage simply wears out. When cartilage wears away, bone rubs on bone causing severe pain and disability. The most frequent reason for osteoarthritis is genetic, since the durability of each individuals cartilage is based on genetics.
If your parents have arthritis, you may also get it.
Trauma – can also lead to osteoarthritis. A bad fall or blow to the knee can injure the joint. If the injury does not heal properly, extra force may be placed on the joint, which over time can cause the cartilage to wear away.
Inflammatory Arthritis – swelling and heat (inflammation) of the joint lining causes a release of enzymes which soften and eventually destroy the cartilage. Rheumatoid arthritis, Lupus and psoriatic arthritis are inflammatory in nature.
Total knee replacements are usually performed on people suffering from severe arthritic conditions. Most patients who have artificial knees are over age 55, but the procedure is performed in younger people.
The circumstances vary somewhat, but generally you would be considered for a total knee replacement if:
- You have daily pain.
- Your pain is severe enough to restrict not only work and recreation but also the ordinary activities of daily living.
- You have significant stiffness of your knee.
- You have significant instability (constant giving way) of your knee.
- You have significant deformity (knock-knees or bowlegs).
Knee replacement is removing the edges of the joint that have been diseased by degeneration or trauma. Knee resurfacing is like a retread. The only part of the joint that is resurfaced is the side of the joint that is diseased.
Most of the patients with severe crippling arthritis have severe affection of both knee joints and deformities.
The advantages of replacing both knees simultaneously in one stage are :
- Single anaesthesia and hospitalisation
- One time medication and rehabilitation
- More economical
The patients who undergo simultaneous bilateral TKR definitely have more cardio-respiratory fluctuations than staged joint replacement but choosing the right patient, having good intensive care and cardiac back up, our experience has been good with no significant increase in complication rate and equally good results when compared to staged procedure (one knee at a time)
Revision surgery is different in that the original components are removed and new components are implanted. The technical aspects of the surgery are more complex than the original total knee replacement. However, the preparation for surgery and hospital experience tend to be very similar to the primary knee replacement.
If a knee is infected the patient is first given antibiotics. If the infection does not clear up, the implant will have to be taken out and the patient is scheduled for revision surgery. The original components are removed and a block of polyethylene cement treated with antibiotics (known as a spacer block) is inserted into the knee joint for six weeks. During this time the patient is also treated with intravenous (I.V.) antibiotics. After a minimum of six weeks, new knee components are implanted.
Any surgery has risks. There are many risks associated with knee replacement surgery. However, in the hands of a well-trained, dedicated orthopaedic surgeon, these risks should be quite low. It is fair to say that you have about a 96% chance that you will go through the operation without any significant complication occurring. The most common complication is blood clots in the legs. The most serious complication is infection. The most important long-term complication is loosening.
You may feel some numbness in the skin around your incision. You also may feel some stiffness, particularly with excessive bending activities. Improvement of knee motion is a goal of total knee replacement, but restoration of full motion is uncommon. The motion of your knee replacement after surgery is predicted by the motion of your knee prior to surgery. Most patients can expect to nearly fully straighten the replaced knee and to bend the knee sufficiently to go up and down stairs and get in and out of a car. Kneeling is usually uncomfortable, but it is not harmful. Occasionally, you may feel some soft clicking of the metal and plastic with knee bending or walking. These differences often diminish with time and most patients find these are minor, compared to the pain and limited function they experienced prior to surgery.
Getting full range of motion, strength and flexibility back in that joint after surgery usually takes months. That’s where pre-operative exercise and education and post-operative physiotherapy programs come in – to ensure you’re physically and emotionally prepared for surgery, and to maximize your recovery after surgery. Together, such programs are among the most important determinants in the success of your surgery.
Even though you may increase your activity level after a knee replacement, you should avoid high-demand or high-impact activities. You should definitely avoid running or jogging, contact sports, jumping sports, and high impact aerobics.
You should also try to avoid vigorous walking or hiking, skiing, tennis, repetitive lifting exceeding 50 pounds, and repetitive aerobic stair climbing. The safest aerobic exercise is biking (stationary or traditional) because it places very little stress on the knee joint.