Knee replacement surgery
An operation to replace parts of the knee with artificial implants.
What is knee replacement surgery?
Knee replacement surgery is an operation to replace worn-out, diseased, or damaged parts of the knee joint with artificial parts. The procedure is also known as arthroplasty.
The most common reason for a knee replacement is pain and loss of movement caused by osteoarthritis.
In your knee joint, the ends of your thigh and shin bones are covered in cartilage. This lets the bones move smoothly against each other. The cartilage in your knees can be damaged by injury or worn away by arthritis, which makes moving your knee stiff and painful.
You may need a knee replacement if non-surgical options, such physiotherapy, activity modifications, offloading splints, painkillers, weight loss, and injections, haven’t helped.
There are two main types of knee replacement surgery – total and partial. Your orthopaedic surgeon will recommend what type of treatment is right for you.
Total knee replacement
In a total knee replacement operation, both sides of your knee joint are replaced with parts made of metal or plastic.
Usually, the underside of the kneecap is also replaced with a smooth plastic dome.
Partial knee replacement
A partial knee replacement is sometimes called a ‘half-knee’ or ‘unicompartmental’ knee replacement.
This usually has a quicker recovery period than a total knee replacement.
A knee replacement is usually carried out under general or spinal anaesthetic. In spinal anaesthetic, his means you’ll be awake during the operation but the anaesthetic blocks feeling from your waist down.
It can also be done under general anaesthetic, which means you’ll be asleep.
Your surgeon will make a cut down the front of your knee so they can access your knee joint. They will remove the damaged ends of your shin and thigh bone.
The ends of the bones will be shaped and measured precisely so that the artificial knee joint can be fitted. The back of your kneecap may also be replaced if needed.
Your surgeon will then close your wound with stitches. It will be dressed and bandaged tightly to reduce swelling. Knee replacement surgery usually takes up to two hours.
After a knee replacement, you’ll need to stay in hospital for up to five days.
You’ll be given painkillers to help relieve any pain. There may be a tube attached to your knee to help drain any fluid that builds up around your knee.
You will be encouraged to start walking around on crutches, usually within 24 hours. Our physiotherapy team will teach you exercises to help strengthen your knee and will also apply a Game Ready ice machine to help reduce pain and swelling following the operation.
You will need some help when you get home. It’s a good idea to arrange for a family member or friend to stay with you for the first few days.
It can take between six and 12 weeks to recover from surgery, but everyone is different. Your consultant will let you know when you can go back to everyday activities like work, driving, and sport.
Paying for your treatment
We welcome both self-paying and insured patients.
Self-pay patients
We offer several ways for patients to self-pay, including pay-as-you-go and self-pay packages.
Insured patients
At Cromwell Hospital, we accept private health insurance from most major providers, including AXA, Aviva, Bupa, and Vitality.
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