Knee replacement

What is a knee replacement?

A total knee replacement is carried out to treat knee pain, usually due to knee osteoarthritis, which is gradual wear and tear of the joint.

During the procedure, both sides of the damaged joint are removed and replaced with an artificial joint (a prosthesis or implant). There are many different types of knee replacement and your surgeon will recommend the one that’s best for you.

Is a knee replacement right for me?

Your consultant may recommend a knee replacement if:

You can be any age to have a knee replacement, but most people who have one are 60–80 years old.

What are the benefits of a knee replacement?

Your knee will be much less painful and the joint should move more smoothly, so you’ll be able to walk around more easily.

How long do the benefits last?

Knee replacements can wear out over time, depending on your body weight and how active you are. Most people’s knee replacements last around 15 years. After that time, you’ll need a knee replacement revision.

What happens during a knee replacement?

A knee replacement usually takes around 1–1.5 hours. It’s usually done under general anaesthetic, so you’ll be asleep.

Before the procedure

There are a few things you can do in the lead up to the procedure to make sure everything goes as smoothly as possible:

• Let your doctor know about any medication you take and follow their instructions
• If you smoke, stop smoking several weeks before the operation
• Try to maintain a healthy weight
• Exercise regularly
• Don’t shave or wax the area where a cut is likely to be made
• Try to have a bath or shower either the day before or on the day of the operation.

During the procedure

1. Once you’re under anaesthetic, your surgeon will make a cut on the front of your knee and remove the damaged joint surfaces
2. Then they’ll insert an artificial knee joint – this will either be fixed to the bone with acrylic cement, or have a special coating that bonds directly to the bone
3. Finally, they’ll close the skin with stitches or clips.

After the procedure

You’ll be taken to the recovery room where you’ll wake up. A nurse will be there to look after you. You’ll have a large dressing covering your wound and you may have a small tube coming out of it to drain away any excess fluid.

You may also have a drip (infusion) going into your arm to keep you hydrated and give you pain relief. The nurse will check your wound, blood pressure and pulse, and when you’re ready, they’ll take you to your room.

Recovery from knee replacement

You’ll usually be in hospital for around 2–4 days. Most people make a good recovery and return to normal activities within 6 weeks. It can take around 6 to 12 months for your knee to fully recover.

Short-term recovery

When you’re back in your room, the nurse will keep checking on you to make sure you’re recovering well. Once the anaesthetic has worn off, you’ll be able to have something to eat and drink, and start moving your legs.

While you’re in bed, you may have help with the circulation in your legs to prevent blood clots. This can include:

• Wearing boots that are inflated with air for the first 2 days
• Wearing support stockings, which you should leave on for 4–6 weeks
• Daily injections or tablets, which you may have for up to 6 weeks

Walking around again

We understand you may be nervous about getting up for the first time, but we’ll be there to help you whenever you’re ready.

• Day of surgery: A physiotherapist will give you some exercises to do while you’re in bed to help your new knee joint move and strengthen the muscles around it.
• Day after surgery: You’ll have an X-ray to check the position of your new knee. The physiotherapist will help you get out of bed and take your first steps – you may need to use a frame to start with. The nurse will then help you walk around until you can do this yourself. You should repeat your exercises hourly.
• Second and third day after surgery: An occupational therapist will give you some tips for getting on and off the bed, chair and toilet, as well as washing and dressing. The physiotherapist will help you transfer to crutches or a walking stick, before giving you some more exercises to increase your movement.

You’ll be able to go home as soon as you can walk up and down stairs safely and the healthcare team are happy with your recovery.

You won’t be able to drive, so you’ll need someone to come and take you home.

Managing your recovery at home

To begin with, it’s normal to experience:

• tiredness – get plenty of rest, but then it’s important to slowly increase your activity
• swelling – to ease this, keep your leg raised when sitting and apply an ice pack wrapped in a tea towel
• pain – take any painkillers we’ve prescribed until you’re pain free

Here are a few things you can do to strengthen your knee, avoid damaging it and help your wound heal:

• Keep your wound dry for 4–5 days afterwards, and use a waterproof dressing when you have a bath or shower
• Continue the exercises the physiotherapist showed you
• Try low-impact exercises like walking and gradually increase how far you walk
• Keep using your crutches or walking stick for as long as you feel you need to
• Don’t lift anything heavy or do any strenuous exercise
• You’ll be able to bend your knee 90 to 120 degrees, but you should avoid kneeling down
• Don’t sit with your legs crossed for the first 6 weeks
• Avoid twisting at your knee

Call the healthcare team if you have any questions or concerns about anything.

Driving after a knee replacement

You should be able to start driving again after about 6–8 weeks, as long as you can operate the pedals and control your car in all situations. Always check with your insurance company and your doctor first.

Time off work

It’s important to take time off to rest, but getting back to your routine as soon as possible can help you recover faster.

If you have a desk job, you’ll be able to return to work after around 8 weeks. If you job is more physically demanding, you’ll need to wait around 12 weeks. If you’re not sure, check with your doctor.

Follow-up appointments

You’ll need to come back to have your stitches or staples removed about 2 weeks afterwards. Then you’ll have a check-up around 6–12 weeks after your surgery to make sure you’re recovering well. We’ll arrange these appointments with you before you leave the hospital.

Alternative treatment options

You don’t always need surgery for knee pain, and usually it can be eased through non-invasive measures:

• Painkillers can help control the pain
• Using a walking stick can make walking easier
• Wearing an elasticated support on your knee can help it feel stronger
• Regular moderate exercise can reduce the stiffness in your knee
• Physiotherapy can strengthen weak muscles
• Losing weight if you’re overweight can reduce the load on your knee
• Joint injections can reduce pain and stiffness for several months

If your arthritis is minimal, and you’re under 65, you may be able to have a partial knee replacement. With this surgery, the knee tends to bend better and feel more like a normal knee than it would with total knee replacement.

Risks

Complications are rare but possible. Rest assured that your consultant will weigh up the risks and advantages with you when deciding if they recommend surgery. Your consultant will also discuss any additional risks that apply to your situation at your initial consultation.

Complications of knee replacement surgery are rare, but you could experience:

• knee stiffness
• infection of the wound
• infection of the joint replacement, needing further surgery
• unexpected bleeding into the knee joint
• ligament, artery or nerve damage in the area around the knee joint
• deep vein thrombosis (DVT)
• persistent pain in the knee.