I’ve just been told that I have osteoarthritis in my knee!
Ok, I’m an Exercise Physiologist and I have been explaining the causes and process of osteoarthritis (OA) and prescribing exercise treatment plans to clients for almost 20 years. Well, 2 weeks ago my daughter challenged me to a sprint, of which I accepted the challenge. Two things happened, she beat me and I hurt my knee!
After a week of ongoing joint swelling I asked a Physiotherapy colleague of mine to take a look at my knee, just to rule out any structural or soft tissue issues. At the end of the consult Derek confirmed that the structural integrity of my knee was fine but I had signs of OA.
OA, me! Only my older clients suffer from OA and then the cruel truth of reality of my 48 years on the earth hit me in the face.
Most people understand that OA is wear and tear of a joint, but what does this mean?
Generally OA takes many years to manifest and get to a point that the joint becomes painful. Pain is the inflammatory response to joint wear and tear that starts a process of many changes that occur for the body to manage the pain.
Using knee OA as an example, once the brain registers pain it will start a process of guarding to reduce the mechanical loading of the affected knee joint. Although this is a protection mechanism this is where the real negative affects of knee OA commence. The guarding mechanism of the brain is to unload the sore knee. This involves taking weight off the involved leg at rest, altered hip mechanics when walking to avoid end range extension and loading of the knee. The net result of altered motor control of the involved knee means that the muscles involved in moving and stabilising the involved knee suffer atrophy (shrink). In addition, the muscles on the opposite side of the body start to bear increased load to compensate for the OA knee, leading to increased mechanical loading of the opposite ankle, knee and hip joints, placing them at risk of increased wear and tear.
So what is the best approach to manage knee OA? Reducing pain and therefore inflammation of the joint is the starting point and depending on the level of pain conservative management using non-steroidal anti-inflammatory medication or Physiotherapy is a good start. However, if compensatory motor control changes are not addressed the knee will be susceptible to further damage.