What is total knee replacement surgery?

Knee replacement surgery replaces the damaged knee joint surfaces with new components typically made from polyethylene and metal. Bone cement may be used to attach the metal implants to the bone. It is recognised as one of the most common orthopaedic surgeries.

Why is total knee replacement surgery needed?

Patients requiring total knee replacement surgery will typically have their knee joint damaged from arthritis, manifesting itself in impaired function, and progressive pain.

Osteoarthritis is recognised as one of the most common reasons for needing total knee replacement surgery. The condition involves cartilage deterioration which means that the bone and knee joints no longer have sufficient cushioning. Other conditions which cause progressive pain and the continued impairment of the knee’s function – such as a broken bone or rheumatoid arthritis – can also be reasons why a patient might consider total knee replacement surgery.

What can I expect from the procedure?

Ahead of total knee replacement surgery, the surgeon will talk about the procedure with a patient, before asking them to complete a consent form. An anaesthetist will also discuss the form of anaesthesia used – either spinal or general anaesthetic – before the patient enters the operating room.

During the procedure itself, the femur bone’s end will be removed and replaced by the surgeon with a metal shell. Then the top of the tibia, that is the leg bone, is also removed and replaced with a metal tray with a stem. A piece of plastic is then used as a spacer between the two metal components. Sometimes, depending on the condition of the kneecap, a ‘button’ made from plastic can be installed under the surface of the kneecap.

In total knee replacement surgery, the posterior cruciate ligament can be retained or swapped for a post made from polyethylene.

Recovery time

Following total knee replacement surgery, patients typically undergo enhanced recovery programme. Patients are allowed full weightbearing as soon as possible with walking aids. Patients stay in hospital for 3-4 days after which time they can look forward to resuming normal activities in around six weeks. Swelling and pain can take up to 3-6 months to resolve.