What is total knee replacement surgery?
Total knee replacement surgery involves removing the damaged knee joint and replacing with a new synthetic joint (prosthesis). Also called knee arthroplasty, this procedure is most commonly used to treat severe knee osteoarthritis, which is a wearing out of the cartilage layers inside the knee. Eventually, the cartilage inside the knee may be completely worn away and bone on bone movement occurs with every step. This leads to relentless pain, stiffness, swelling and deformity.
Knee replacement surgery is becoming more and more common in Australia, with almost 50,000 knee replacements performed last year. Due to improved surgical techniques and better prostheses, knee replacement surgery has a high success rate for relieving pain and restoring mobility. Around 80% of people who undergo knee replacement surgery are happy with the results.
Based on the Gold Coast, our lower limb specialist orthopaedic surgeons specialise in knee replacement surgery.
Do I need a total knee replacement?
A total knee replacement might be recommended if you have:
- severe osteoarthritis
- rheumatoid arthritis
- avascular necrosis of the knee
- bone growth disorders
After discussion with your doctors, the decision to have a knee replacement is yours and yours alone to make. Your doctors will always give you the options and only offer the surgeryif appropriate. The recommendation is usually made keeping in mind the following factors:
- pain that has not been relieved by pain medication, physiotherapy or walking aids
- pain severe enough that it prevents work, walking, recreation and daily activities
- sleep is disturbed due to pain
- stiff and swollen knee
- X-rays confirm the presence of arthritis
How does knee replacement surgery work?
Knee replacement is done in hospital under general anaesthesia or spinal anaesthesia.
After your knee is cleaned and prepared for surgery, your surgeon makes an incision over your knee, from above the kneecap to below it. This incision may be up to 30 cm long. The soft tissues are then moved to expose your knee joint.
Your surgeon cuts through the bottom of your femur (thighbone) and the top of your tibia (shin bone) and the damaged knee joint is removed. The new prosthetic joint is precisely fitted into position and anchored using bone cement. The soft tissues are then put back into place and the incision is closed with sutures or clips.
How long does knee replacement surgery take?
Knee replacement surgery takes 1-2 hours.
What to expect after surgery?
When you wake up after surgery, your knee will be covered by a dressing and an ice machine will be circulating ice cold water around the knee.
You will be given pain medication, antibiotics to reduce the risk of infection, and usually medication to reduce the risk of blood clots. You will also be encouraged to move your feet to help prevent clot formation.
On the second day after surgery, your therapists will help you start walking again and show you how to perform knee exercises. Most people are in hospital for 3-5 days after total knee replacement surgery.
Recovery after a knee replacement takes time and this time varies considerably from person to person. Full recovery typically takes 6–12 months. During this period strength and flexibility should steadily improve.
Many people ask if their knee replacement will be detected at airport scanners. A recent study has shown that 90% of all total hip and knee replacements will be detected by a typical walk through metal detector at an airport. Upper limb replacements such as shoulder, radial head and wrist replacements are less likely to set off the alarm. Metal plates and screws are also much less likely to create a problem at the airport. Implants made of titanium and chrome/cobalt alloys (common with joint replacements) tend to trigger the detectors more so than stainless steel (more commonly used for plates and screws).
It’s important to allow some more time at the airport to clear the screening process. Inform the security officer that you have a joint replacement before walking through the security gate. They will most likely need to perform additional tests such as passing a handheld detector wand over your body or a pat down. There is no evidence this process affects your joint replacement.