What is osteoarthritis of the knee?
Osteoarthritis of the knee (often shortened to OA knee) is a common complaint. About 13% of women and 10% of men aged 60 years have symptomatic OA knees. This percentage is seen to increase with age. Although there are reasons why OA knee may start to be a problem earlier, it is most commonly seen to develop past the age of 45.
As practitioners who spend an awful lot of time speaking to people with OA knee. We hear time and time again the descriptive terms:
- Wear and tear
- Old age
- Damage from years of sport.
It could be said that these terms when used are a good way of normalizing a problem, which enables folk to crack on with life. However this level of understanding doesn’t necessarily leave much scope for improving matters. We cannot make people younger, magically take away wear or hop back in time and take away previous sporting injuries. Does this mean that OA knee cannot therefore be improved? The answer here is no; there are many things that can be done with OA knee.
What we see commonly, both in clinical practice and in research, is that people have wear within their joints but they cope perfectly well with this and report no symptoms. Wear can also increase with age and still symptoms do not present. Wear and tear is therefore a distinct entity compared to osteoarthritis.
When we use academic research techniques to look into what underpins the pain and stiffness of OA knee we see some features consistent with wear and tear such as:
- Cartilage becoming rough and thin.
However it is how the joint responds to these changes that set the processes apart. The features below are changes in and around the joint that are partly the result of the healing (inflammatory) process and partly an attempt by your body to repair the damage.
- A reduction in your joints natural lubricants (hyaluronan)
- The bone underneath the cartilage reacts by growing thicker and becoming broader.
- All the tissues in your joint become more active than normal, as if your body is trying to repair the damage.
- The bone at the edge of your joint grows outwards, forming bony spurs called osteophytes.
- The joint lining (synovium) may swell and produce extra fluid, causing the joint to swell.
- The capsule and ligaments slowly thicken and contract (shorten).
Sometimes these repairs work but sometimes they do not and things start to change within the joint.
We therefore get secondary changes such as the stiffness, inflammation and joint swelling that are features that can often be changed with treatment that are not directly related to the wear and tear process.
We are more likely to get OA knee predominantly due to three factors:
- Previous injury
We all get old (hopefully), we all get wear and tear, but we don’t all get OA knee. It is the above response to damage or wear that is the difference between having symptoms of OA knee and just having a knee with wear.
This is brought into stark relief when you compare two situations that one would think would both increase the amount of wear within a joint but frequently have different relationships with OA knee.
People who are obese, that is they have a body mass index (BMI) of over 30 are more likely to have OA knee. This would seem logical wouldn’t it? More weight means more wear? But they are also more likely to have OA at the base of their thumbs. Yet in marathon running populations there is no higher risk of OA knee. This would suggest that the level of mechanical wear is not the whole story: More on this later.
What are the symptoms of OA knee?
Symptoms commonly come and go in episodes, certainly at the beginning. This can often be related to things such as your activity levels and even the weather. As matters progress the symptoms can be continuous.
The primary symptom of OA knee is pain localized to the knee. The vast majority of our treatments are aimed at reducing pain and thus helping life go smoother.
Other symptoms could include:
- Joint tenderness
- Increased pain and stiffness when you have not moved your joints for a while
- Joints appearing slightly larger or more 'knobbly' than usual
- A grating or crackling sound or sensation in your joints
- Limited range of movement in your joints
- Weakness and muscle wasting
What can I do for myself?
Having OA knee does not put a ceiling on your potential physical activity levels. It is not possible to predict the level of disability in a person simply from an x-ray. When it is possible to, a well-controlled OA knee should allow most people to undertake all the activities they wish.
What is clinically evident however is that OA knees don’t cope well with big and sudden fluctuations in activity. To help yourself it is thus good to:
- Maintain a level of regular activity to maintain good joint function.
- Plan increases in activity methodically. For example if you are planning a walking holiday, make sure that you have walked the distances you intend to cover before hand. If not train yourself.
Another thing to think about is your general health. We have written a comprehensive piece on maintaining good musculoskeletal health here.
To bring us back to the topic of obesity as discussed above. It would appear that it is not only the extra load placed on the knee that leads to an increased chance of OA. The fact that OA at the base of the thumb (somewhere unaffected by added body weight) is also more likely to be present when obese suggests that underlying health may affect the quality of joint cartilage and thus increase the risk of OA. It is therefore very important to try to maintain a normal weight (BMI between 18.5 and 25)
Due to the effects that OA knee has on joint mobility and the fact that pain and swelling is seen to lead to muscle weakness it can also sometimes help to undertake some specific knee exercises.
These exercises are a great place to start.
Finally if you are wondering whether you are feeling too old to start increasing activity I would like you to reflect on the legendary Charles Eugster.
What other treatments are available?
Hyaluronic acid joint injection.
In presentations where you are getting pain from an OA knee in the absence of significant inflammation you may benefit from a Hyaluronic acid joint injection. This mimics the hyaluronan, the naturally occurring lubricant within your knee. Injections of hyaluronic acid can reduce pain and stiffness. More information can be found here. These injections can be undertaken by our knee specialists here at Cycloform Physiotherapy. To find more information about booking click here.
Corticosteroid is a very effective anti-inflammatory. When administered into the knee joint directly by injection it is excellent at reducing the pain and swelling of an arthritic flare up. These injections can be undertaken by our knee specialists here at Cycloform Physiotherapy. To find more information about booking click here.
A physiotherapy session with one of our knee specialists at Cycloform Physiotherapy will include a bespoke assessment, diagnosis and then identification of your treatment needs. This may include
- Manual therapy (manipulation),
- Strength and conditioning exercise.
- Advice. You will be able to draw on our experts many years of treatment experience to help you regain control of your symptoms.
Bracing and orthotics
At Cycloform Physiotherapy our knee specialists are able to recommend the appropriate appliance for your needs.
At Cycloform Physiotherapy our knee specialists have many years of experience of working along side specialist knee surgeons here in York. Our excellent working relationships based on years of mutual respect and many hours working closely in clinics together mean we are well placed to be able to give you help with making the decision about when the time may be right to contemplate a surgical solution to your OA knee. Because of these relationships we are also able to communicate with a chosen consultant to help smooth out the transition. We can even help you choose your consultant and the hospital where you may wish to go. Common surgical procedures undertaken in the treatment of OA knee include:
- Total Knee Replacement
- Unicompartmental Knee Replacement