Donald Rumsfeld, previous US Defence Secretary, is infamous for his quote about ‘known knowns’ and ‘unknown unknowns’. Poor man – how one statement can haunt you for the rest of your life! It’s odd, but this quote keeps on popping into my head at the moment. The more I find out about multiple sclerosis, the more I realise I don’t know, plus how little the scientists know – and don’t know! There are many ‘unknown unknowns’!
During my many years working as a nurse, I have looked after a number of patients with MS. A few were hospitalised because of their condition, but most were in for unrelated reasons. I thought I knew what MS was and how it affected people, but now I’m on the other side, it amazes me how little I really knew. I must have really annoyed some of my patients. It’s not surprising, therefore, that people who have never been exposed to this crazy condition lack understanding and are prone to making assumptions about the condition, and you as a person. This is one of the top frustrations and irritants discussed on the various MS message boards and Facebook groups I’ve subscribed to.
One of the things that mystifies a lot of people is that there is often no outward sign of what is going on inside a person with MS. You may look perfectly fit and healthy, but feel terrible and find it hard to even get out of bed. People know it’s a condition that affects your nerves and tend to associate it with being unable to walk – if your legs work, you must be fine. As I’ve said previously, MS affects everyone differently (hence it’s known as a snowflake condition) and there’s a whole multitude of things that can be going on behind ‘closed doors’.
When someone asks me about MS, I try to explain it as simply as possible. To start to understand it, we need to know about magical myelin and it’s role in nerve conduction.
The nervous system is a constant communication network, sending and receiving messages around the body, controlling more information than any super computer could (I think!). These messages have to move fast; time really is of the essence when it comes to many bodily functions. So to maximise the messaging speed, nerves are covered with a special fatty insulation called myelin. I picture it like the lagging on a pipe or the cover on a hot water tank – a thick coating with regular indentations (where the lagging is tied in place). This special fatty lagging on a nerve enables an impulse to jump from indentation to indentation rather than travel down the whole nerve. This means information can get where it’s going super fast.
The nervous system is split into two parts – central and peripheral. The central nervous system (CNS) is made up of the brain and spinal cord and includes 12 key special nerves which includes the optic nerve. The peripheral nervous system (PNS) includes all the other nerves in your body. The CNS is the main system that has control over the rest of the body, translating messages coming in and sending out actions that need to be done, all performed in a tiny moment. Both the CNS and PNS contain myelin (the fatty lagging), but in MS it’s only the CNS myelin that is attacked.
For some reason, something triggers the immune system to see the CNS myelin as a foreign body that needs to be destroyed (one of the known unknowns) and starts to break it down, like a mouse nibbling away at a pipe’s lagging. This is ‘demyelination’. Once myelin is removed, it seriously slows down the speed nerve impulses can travel at; it can even block messages getting through. This happens in the brain and/or the spinal cord and consequently causes chaos in the body, effectively having an impact on any sensory or motor function. On an MRI scan, areas that have been nibbled show up as white patches, or lesions; these are places where myelin has been destroyed. Some people with MS have loads, others have only a few. The effect they have on the body can, but not always, depend on number and location, hence the variety and intensity of symptoms.
Up to this point, it’s been thought that once destroyed, myelin cannot be replaced. Fortunately we live in exciting times and there’s lots of research going on, not only to work out the immune system decides to attack myelin, but also how to try and regrow it. In the meantime, it’s up to me to do everything I can to stop any more of my myelin being nibbled away. I can also deal with the known knowns, try not to worry too much about the unknown knowns, and keep an open mind about the unknown knowns. Myelin is precious stuff, and it can get on, and stay on, my nerves as much as it wants to!