Modern knee replacements last for at least 20 years in around 8 out of 10 patients. In more active patients the joints may wear out more quickly. However, it’s usually possible to have further knee replacements, if necessary.
Because knee replacement surgery is a major operation it's normally only considered if you have severe pain and serious mobility difficulties, and if your arthritis isn’t responding to other measures. The operation works best for patients whose joint surface has worn right down to the bone (bone- on-bone arthritis). If your symptoms are still manageable and your medication is effective then you may prefer to wait. You should try to lose weight if you are overweight and you should also try physiotherapy if you have not already done so. Your orthopaedic surgeon will be able to advise on the surgical options and the potential pros and cons of having or delaying surgery, taking into account your age, health and level of activity.
Most people who have a knee replacement are over 60. The earlier you have a knee replacement the greater the chances that you’ll eventually need further surgery. However, there’s evidence that the surgical outcome may be better if you don’t wait until the knee becomes very stiff or deformed. Unfortunately, some people may not be able to have a knee replacement even though their arthritis is very bad:
- If the thigh muscles (quadriceps) are very weak they may not be able to support the new knee joint.
- If there are deep or long-lasting open sores (ulcers) in the skin below the knee the risk of infection may be too great to consider surgery
Freedom from pain is the main advantage of a knee replacement, and you should expect to become more mobile too. Everyday activities including driving or climbing stairs should become easier, and exercise such as swimming, cycling, tennis or golf should also be possible.
Research has shown that four out of five people who've had knee replacement surgery are happy with their new knees. For those who aren't happy, the main reason is continuing pain, which may not be due to a problem with the operation. This is more of a risk if you have relatively minor joint damage (which may still cause severe symptoms) before surgery. If your joint damage isn't very severe it may be better to carry on with non-surgical treatment rather than risk a poor outcome from surgery.
We now know that knee replacements are not so likely to be effective in the early stages of arthritis. We can be much more confident that the operation is likely to be effective where the arthritis is more advanced.
A replacement knee can never be quite as good as a natural knee. Most knee replacements aren’t designed to bend as far as your natural knee. You may also have some clicking or clunking in the knee replacement. However, most people rate the artificial joint about three-quarters normal.
It’s usually possible to kneel, although some people find it uncomfortable to put weight on the scar at the front of the knee. To begin with, there will be some numbness on the outer edge of the scar. It’s unlikely that the feeling will completely return to normal but it usually improves over about two years.
A replacement knee joint may wear out after a time or become loose. For most people an artificial knee will last for 20 years or more. Younger patients are more likely to need a repeat knee operation at some point in later life. The likelihood of needing another operation is increased if you’re overweight or do heavy manual work. Running or playing vigorous sport can also increase the risk of wear or loosening of the new joint.Artificial joints can be replaced again if necessary, although revision surgery is more complex and the benefits tend to lessen with each revision.
The human hip is a ball and socket joint. It is the most flexible and free-moving joint in the body, and can move backwards and forwards, to the side, and can perform twisting motions. Full function of the hip is dependent on the coordination of bones, muscles, tendons, ligaments and nerves.
Hip pain can be caused by a variety of factors, including:
- An injury that does not heal properly
- A chronic illness
- Normal wear and tear from years of constant use.
- Severe arthritic conditions, especially osteoarthritis
- Injuries as a result of trauma, such as a hip fracture or dislocation caused by a fall.
If hip replacement surgery is the best treatment option for you, your physician will refer you to an orthopaedic surgeon with expertise in this procedure. Your orthopaedic surgeon will evaluate your hip joint with a full physical exam and X-rays and develop a treatment plan about how surgery can best benefit you. Your surgeon will also ask you about any past medical problems