What is knee osteoarthritis?
Osteoarthritis of the knee joint is very common and can be thought of as a wear and tear condition of the cartilage knee – however recent research suggests that there is a strong inflammatory component to knee arthritis as well and that the underlying pathology is much more complicated than originally thought.
There are many different causes, although in the majority of cases it is referred to as primary osteoarthritis – the knee joint has worn out. Other secondary causes include infection, fractures, previous surgery, gout, and rheumatoid arthritis amongst others.
Knee arthritis most commonly affects the medial (closest to the midline of the body) part of the knee, but it can also affect just the patellofemoral joint, the lateral part of the knee or in some cases the entire knee joint.
What are the symptoms of knee osteoarthritis?
The main symptom of knee arthritis is pain. Importantly, the pain tends to be worse at the beginning of the day, worse following exercise and can wake patients up at night. Stiffness is also a common symptom and can be worse following prolonged sitting. When knee arthritis becomes more severe than patients often describe a reduction in the range of movement of the knee, with an inability to fully straighten the knee being the commonest finding.
How is it diagnosed?
Knee osteoarthritis is diagnosed on the basis of X rays. Rarely, if there is some confusion regarding the diagnosis, an MRI may be needed, however, this is unusual.
What are my options for treatment?
In the first instance, physiotherapy to strengthen the muscles around the knee are very important. This can be helped with injections into the knee to control the pain in the short term. When these measures fail to help, bracing can be useful. There is some evidence for realignment surgery around the knee although this must be approached with caution as results can be unreliable. In those with established arthritis and symptoms not controlled by non-operative measures, then joint replacement is an excellent option. We always encourage partial joint replacement where possible, although total knee replacement is also an excellent option.
The vast majority of our patients go home on the same day following a partial knee replacement or the next day following total knee replacement.
Over 80% of knee replacements (whether partial or total) are still in place and functioning well at 20 years post operation.