If you suffer from severe arthritis of the knee that remains painful despite treatment with medicines, exercise, rest and supports to assist your mobility, you may benefit from a knee replacement.
The main reason that people with arthritis have knee replacements is unrelieved pain — if you are adequately mobile and your pain is manageable, you probably do not need a knee replacement.
Your suitability for knee replacement surgery will be assessed based on your medical history, physical examination, X-ray and other imaging results.
The most common reason that people have a knee replacement is arthritis of the knees that causes ongoing pain and reduced mobility.
The main types of arthritis include:
For some people affected by arthritis of the knee, knee replacement surgery (also known as a knee arthroplasty) may offer an improvement in their quality of life through reduced pain and increased mobility.
A knee replacement operation will usually take between one and 2 hours. After evaluation by an anaesthetist, you will be given either a general anaesthetic (which causes complete sedation) or a spinal anaesthetic (where you remain awake but are anaesthetised from the waist down).
A knee reconstruction involves surgery to replace your knee joint with a prosthesis—an artificial knee joint. Mostly, these prostheses are made of plastic and metal, and consist of 3 main components:
The metal femoral and tibial components are attached to the end of the femur (thigh bone) and the top of the tibia (shin bone). On the end of the metal components is a polyethylene (plastic) coating which acts as replacement cartilage. The patella (kneecap) may be resurfaced with a plastic button in some cases.
More than 90 per cent of knee replacements last for more than 15 years, depending on your level of activity and weight. The heavier and more active you are, the more quickly they will wear out. Knee replacements can be replaced again if they wear out, although revision surgery is generally more difficult than the initial replacement.
Most people spend about 5 to 7 days in hospital, depending on their progress and rehabilitation.
A blood clot in the leg is a complication that can happen after knee replacement surgery. Your surgeon will provide you with a programme designed to prevent blood clots, which usually involves wearing special compression stockings and taking anticoagulant therapy for a period of time after the surgery.
Some warning signs of blood clots include:
Although infection of the knee joint can occur, this is quite rare.
It is important to plan ahead for your recovery from knee replacement surgery. Here are some tips to help make your home accessible after surgery and to promote a fast recovery.
Physiotherapists can help greatly with rehabilitation, while occupational therapists are helpful in making sure your home is safe and advising on any modifications or appliances that may be needed.
Last Reviewed: 20 November 2015