Total knee replacement: A quick guide

A total knee replacement is a procedure that can offer incredible benefits to patients who suffer from knee pain. In his latest online article, renowned consultant orthopaedic surgeon Mr Tim Harris explains everything you need to know about this procedure.

What is a total knee replacement?

The knee joint is a bit like a hinge joint. The joint is made up of the ends of the thigh bone (femur), the shin bone (tibia) and the back of the knee cap (patella). A total knee replacement is an operation to replace the worn knee joint. During the operation, the worn surfaces of your knee joint are removed and replaced with smooth artificial surfaces.

A total knee replacement operation is usually carried out for severe arthritic conditions and has proved to be a very successful procedure. Approximately 90% of knee replacements will still be okay at 20 years and many will last much longer.

What is the aim of the procedure?

The aim of knee replacement surgery is to improve pain and mobility. For most people, it will get rid of all of their arthritic pain and allow them to return to most activities.  However, it will not feel quite like your own knee before it was arthritic and most people will say they are aware it is their artificial knee. 

How long does the recovery process take?

We aim to get people up and walking within a few hours of the operation and around two in three patients will go home the next day (you can go home the same day if you are doing well). Initially, you will be given crutches to help you walk, mainly for confidence and support. Most people will stop using these around the house within a week or two but you are likely to want them when walking outside for a few weeks.

Knee replacement surgery is sore and most patients will be worse off with pain for the first four to six weeks; you will be given painkillers to help and encouraged to use ice to reduce the pain and swelling. By six weeks you will usually be turning the corner and by three months you will be significantly better than you were pre-surgery. People will have ongoing improvement out to a year as the swelling settles and the movement and strength of the knee improves.

What are the risks of the procedure?

A total knee replacement is a major operation, as with any operation there are some risks. These include general complications such as:

• Stroke
• Heart attacks
• Blood clots (in the legs or in the lungs)
• Difficulty passing urine
• Urinary infections
• Chest infection

Complications specific to total knee replacement include:

• A risk of infection around the replaced knee, which whilst rare at around 1 in 200 (on average) can leave you worse off than you currently are and require further operations.
• A risk of stiffness, hence the importance of engaging actively with the recovery process and using physiotherapy to improve the range of motion and prevent scar tissue from forming post‐operatively.
• A risk of blood clots (deep vein thrombosis and pulmonary embolus); you will be given blood thinners postoperatively to reduce this risk.
• A small risk of damaging nerves, blood vessels, tendons or ligaments around the knee. Long term most patients have good pain relief and are satisfied, however, most patients are aware they have an artificial knee (occasional minor discomfort, clunking noise etc) and it will never feel quite as good or reliable as your own knee would have done when it was normal.
• A small number of patients will have some degree of ongoing pain. Eventually, the joint can wear out and fail, but 90% will still be functioning well at 20 years

If you would like to book a consultation with Mr Tim Harris, you can do so today via his Top Doctors profile.