#treatment - Knee

Knee Replacement

  • Knee arthritis causes pain, stiffness and swelling
  • Early arthritis can be helped by anti-inflammatories, physiotherapy or injections into the joint
  • Severe arthritis requires knee replacement surgery
  • About 90% of knee replacement patients report excellent results, with loss of pain and significant improvement in function
  • About 95% of knee replacements are still working fine after 10 years, with about 80% still working well after 20 years

For those patients where there is significant arthritis in the knee, and where the cartilage covering the bone within the knee has worn away, replacement of the knee with an artificial joint can offer excellent pain relief and restoration of function.

Replacement of a knee joint with a Total Knee Replacement (TKR) involves taking a thin section of bone away from the end of the femur (thigh bone) and another section of bone away from the top of the tibia (shin bone). The bone ends are then replaced by metal surfaces, which are cemented in place with a special bone cement. A polyethylene (plastic) spacer is then placed in between the two metal surfaces. The back of the patella (kneecap), where it rubs against the front of the knee, may also be replaced with a new plastic surface cemented in place, depending on how bad the cartilage damage is in that area.

X-ray of an osteoarthritic knee pre-op.

X-ray of an osteoarthritic knee pre-op.

Photo of a Scorpio Knee prosthesis.

Photo of a Scorpio Knee prosthesis.

Photo of a Knee Replacement inserted into an artificial knee

Photo of a Knee Replacement inserted into an artificial knee

Post-op X-ray after a Total Knee Replacement - view from the front.

Post-op X-ray after a Total Knee Replacement – view from the front.

Post-op X-ray - view from the side.

Post-op X-ray – view from the side.

The results of modern knee replacements are very good, with only somewhere in the region of 5% of TKRs failing within a 10-year period after surgery. However, even the best modern TKRs are only really designed for elderly or low functional demand patients, and if they are put into younger, more active patients then they will tend to wear out quicker.

If a TKR does fail by wearing out or becoming loose, then it can be replaced with a Revision Knee Replacement. However, there will be less bone present, and the operation is technically more demanding, with higher potential complication rates and poorer long-term results,