While an exact ‘cause’ is difficult to find, there are plenty of things that increase our risk of osteoarthritis
By Paul Bolger. Chartered Physiotherapist at Nano Physiotherapy, Kilkenny (www.nanophysio.ie).
I don’t want to get overly philosophical here, but in life there is never truly one ‘cause’ of anything. Nothing is truly independent, nothing stands alone, separate from everything else.
Everything around us is an ongoing process – never quite still or stationary. Never really in some ‘final state’. Even mountains, the most permanent objects around us, are temporary – they are here now and likely for millions of years to come, they change, they weren’t always here and won’t be around forever.
Enough philosophy; get to the point
Ok, so what ‘causes’ osteoarthritis. As the name suggests, inflammatory processes within the joint play a role (osteo- = bone; arthro- = joint; -itis = inflammation). It has something to do with a disruption in the normal balance of breakdown and repair/growth that is always taking place in living tissues.
Most people have heard of cartilage (the smooth, robust tissue coating joint surfaces) and how, in osteoarthritis, we see thinning of cartilage in the joint. But many other structures in and around the joint are affected in osteoarthritis – like the bone underneath the cartilage and around the joint, or the ligaments and capsule surrounding and supporting the joint. Osteoarthritis is a whole-joint condition.
There is no single cause of osteoarthritis that we know of. But there are many risk factors – things that we know influence joint health over a lifetime.
Physical Matters
Serious joint injury (like joint surgery or joint fractures) increases osteoarthritis risk. Excessive, repetitive forces through joints also put us at risk – usually seen in people who have worked in jobs requiring constant, repetitive physical tasks and former athletes who trained excessively.
That said, it is known that our joints love a certain amount of strain, with regular activity, movement and loading important to keep them strong, robust and healthy. Balance is key.
Some people are born with joint deformities that cause alignment issues which increase the risk of osteoarthritis too.
But, perhaps surprisingly to some, not all risk factors are from direct physical causes.
Healthy Body, Healthy Joints
While aging is the single biggest risk factor for developing osteoarthritis, obesity is right up there – having a similar impact on joint health as previous joint injury. While there is greater weight going through the knees and hips of overweight people, this is only a small part of the story. The main reason obesity is associated with osteoarthritis is largely due to the systemic, or whole-body, health effects.
Excess body fat, particularly fat around the midriff, results in increased inflammation throughout the body, which impacts joint health (have a look back at my online article ‘Body Fat & Inflammation’ for more on this).
Conditions affecting metabolism such as diabetes increase the risk of developing osteoarthritis. Metabolism is how our body produces and uses energy – and metabolic health has an impact on the health of the tissues within our body and our joints.
You can’t choose your parents
Some genetic factors increase our risk of developing osteoarthritis. Being female does too. We can’t do a whole lot about these things – but if you have close family members with osteoarthritis then considering cutting down other risk factors in your life is a good idea.
Next week we will look at what we can do to keep our joints healthy throughout our lives and consider the treatment options for those who suffer from osteoarthritis.
