What is a knee replacement?

A knee replacement is a type of surgery to replace a damaged knee joint. It is generally considered a safe and effective procedure. Knee replacements can relieve knee pain and allow someone to be more active, if medicines and other non-surgical treatments are not helping.

Knee replacements may be total or partial. In a total knee replacement, the surgeon removes damaged cartilage (the tissue at the ends of bones that cushions the joints) and bone from the surface of the knee joint.

These are replaced with an artificial surface of metal and plastic.

In a partial knee replacement, the surgeon replaces only the affected part of the knee joint and leaves the healthy parts alone.

A knee replacement is also called a knee arthroplasty.

When is it recommended?

The most common reason for a knee replacement is osteoarthritis. Knee replacements are usually considered as a last option to treat persistent severe knee pain or disability after other options have been tried or considered. For a person with arthritis, these other options may include:

• non-impact exercise
• losing weight
• physiotherapy
• medicines

Most people who have a knee replacement are over 60 years of age. If you have the operation when you're under 50, you may need another knee replacement in later life.

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

Knee replacement surgery is generally considered safe and effective. However, complications can include:

• infections
• blood clots in the leg veins
• implant problems
• continued pain
• injury to your nerves or blood vessels during surgery

If the knee becomes red or swollen, your pain gets worse or you become short of breath, go straight back to the hospital emergency department. These could be signs of a blood clot in your leg or your lungs.

Should I have a knee replacement?

To help you decide, you might want to ask your surgeon questions such as:

• What are the alternatives to surgery?
• What are the possible complications and how likely are they?
• What can I expect during the recovery period?
• How much improvement can I realistically expect after surgery?
• Would a new knee last all my life?

How long will it take to recover after the surgery?

Most people leave hospital 1-4 days after a knee replacement surgery. How quickly you get back to normal depends on many factors, including your age and general health and fitness.

You will probably need a cane, crutches or walking frame in the first few weeks and an exercise and physiotherapy program to help you recover.

Most people's strength and flexibility slowly recovers over about 12 months. Following the advice of a physiotherapist and doing rehabilitation exercises as instructed makes the recovery quicker.

Resources and support

You should talk to your health professional about the benefits and risks of getting a medical implant. Use the Therapeutic Goods Administration's guide on what to ask. The information is in English, Arabic, Croatian, Farsi, Greek, Italian, Korean, Mandarin, Spanish, Turkish and Vietnamese.