Osteoarthritis (OA) is a condition where the joint cartilage thins and roughens. The bone below then tries to repair the damage, but sometimes ‘overgrows’ leading to new bony outgrowths or ‘spurs’ on the joints, known as osteophytes. Eventually, as the cartilage wears away, the bones may rub together, causing pain and inflammation. Also, the joint capsule thickens and more synovial fluid may be produced, leading to swelling in the joints. In severe cases the cartilage disappears altogether and the joints become so misshapen that they push the bones out of their normal position, causing deformity.

Unlike many other forms of arthritis, OA affects the joints only and is thought to be largely due to ‘wear and tear’. In effect, OA is a process where the body tries to repair damaged joint tissue. In some cases the joint eventually becomes symptom free, but with a different structure. But in some people this process is unsuccessful – perhaps as a result of ongoing, or extreme trauma to the joint, or a reduction in the body’s ability to heal itself – and the joint damage continues.

Osteoarthritis statistics

Eight-and-a-half million people in the UK suffer from Osteoarthritis. Around half of people reaching the age of 65 have the condition, with symptoms ranging from mild (especially in the early stages of the condition) to severe; around one in ten sufferers aged 65 and over experience severe disability as a result of OA – especially in one or both hips or knees.

What are the symptoms of osteoarthritis?

The main symptoms are those affecting the joints. They usually occur in the fingers, thumbs, hips, knees, spine (including the neck) ankles and sometimes the shoulders and elbows and include:


The pain is mainly due to damaged joints and tense muscles. It can come and go, but tends to increase the more the joint is used - hence the pain is often at its worst in the evening - but improves with rest.


The stiffness usually eases after rest, but joint movement may be limited and the joint may ‘crunch’ or ‘creak’ as it moves - this is called ‘crepitus’.


Swelling of the joints might be due to the synovium swelling slightly and producing more synovial fluid, or it may be down to the presence of osteophytes. The knees are especially prone to swelling after exercise.

Loss of balance

Instability, or loss of balance, when moving about. Some OA sufferers say that their joints ‘give way’.

Reduced mobility and flexibility

All of these symptoms, depending on their severity, can make you less mobile and less able to carry out everyday tasks. For example, if your hips and knees are affected, you may find walking difficult, and if your fingers and thumbs are affected, you may have problems turning a tap on and off, or opening a jar.


This is a fairly common complication of Osteoarthritis. It occurs when calcium deposits form in the cartilage. If these deposits work their way into the synovium, they can cause irritation and hot, painful, swollen joints.