Knee replacement surgery

A total or partial knee replacement removes the affected part of the joint and replaces the damaged joint surface.
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Who needs knee replacement surgery?

The aim of knee replacement surgery is to relieve pain and improve your mobility. You may need knee replacement surgery if you have confirmed arthritis in all or part of your joint and one of the following:

  • Severe pain limiting your everyday life, such as walking and standing.
  • Constant pain through the night.
  • Need for regular pain relief to treat your knee pain.

What is pre-admission clinic?

You will be assessed and helped to improve your health before your surgery.

What happens during surgery?

Surgery is performed under general anaesthetic (you won’t be awake) or under a spinal / epidural anaesthetic, where you are awake but you have no feeling from the waist down. Your surgeon or anesthetist will discuss this with you before you have your surgery.

Your surgeon will remove the worn ends of the bones in your knee and replace them with metal and plastic parts, which are measured to fit your body.

Most patients require a total knee replacement but some patients are suitable to have only part, or one side, of the joint replaced, known as a partial, or unicompartmental knee replacement. Your surgeon will discuss the most suitable option for you.

Benefits of surgery

The outcomes of knee replacement surgery are very good. The majority of people who have surgery are free from pain and the disability from knee arthritis. This will allow most people to regain, or maintain, greater independence.

Most people will return to a very good level of function after knee replacement surgery but it is important to remember that it will not be a normal knee joint, rather a prosthetic one, and you will not necessarily be able to do all the things you were once able to do.

Risks of knee replacement surgery

Complications or side effects that can occur after surgery include:

  • Persistent stiffness in the knee.
  • Ongoing pain around the knee replacement, despite a technically successful operation. This can occur in up to one in 10 people and is more common in people younger than 60 years.
  • Deep vein thrombosis (blood clots) in the leg (about two in every 100 people). You will be given medication to reduce this risk as much as possible.
  • There is a very small risk (about one in every 100 people) of developing a deep seated infection around the knee replacement. This may require the replacement to be taken out and a long course of antibiotics.
  • In rare cases the knee replacement may be unstable or may loosen over time, requiring a revision operation to correct the position of the components.

Your risk of complications is greater if you are overweight, you smoke or you have not been very active before your surgery. You can help to reduce your risk of complications by stopping smoking, losing weight and maintaining strong muscles to help support the knee replacement after your operation. You may want to talk to your GP or health professional about what you can do to improve your health and reduce your risk of complications.

How long you will spend in hospital or on treatment?

Anyone who has knee surgery will need to spend about three days in hospital. This is to ensure there are no complications and that you are fit enough to go home.

You will be expected to be up and active the day after, and sometimes even the day of, surgery. Every day tasks such as walking and getting dressed will be encouraged to return to normal almost straight after your operation. For the first six weeks after your surgery will likely need to use a walking aid such as crutches to help you.

You may start driving again six to 12 weeks after your surgery, although you should check this with your insurance company.

It can take up to two years to fully recover from a knee replacement operation. Your muscles will only be restored through doing exercise, which your physiotherapist will support you with.

Once you’ve had your surgery, you will be required to complete a questionnaire so we can check the outcome of the surgery. You will need to repeat this questionnaire over different time points so we can monitor your progress.

You will also see your surgical team at various time points after the operation to monitor the knee replacement.

If you experience any problems, or you are concerned about your knee replacement after your operation it is important that you discuss this with a health professional.