Structure vs. Function - Part III

Why this debate should matter to you - the therapist and the patient.

The search for structural faults that are causing pain is still going on.
And it'll continue to do so.
I think it has do do with basic human psychology - we have this need to put labels on everything we see. Our brains want easy explanations - all the time.
Our brains produce visual (and other) illusions because they are hardwired to resolve every computational problem they encounter.

They are not computers running Windows; they can't just crash - they have to continue functioning - even if that means finding patterns in meaningless noise (pareidolia, conspiracy theories, astrology).

So where do you - the patient come in?
Well - your expectations are shaped by this mechanism. You want answers when you consult a health care professional. And those answers better fit your view of the world - or else!

Structural faults like ruptured discs, degenerated vertebrae, pulled muscles are easy to put a finger on - just think of an MRI scan that shows a bulging disc. What's easier then to show you - the patient in pain - that picture and explaining that that bulge causes all your problems. And since an operation could clear that right up you could be pain free again in a week or so.
It's convenient, easy, convincing - and even fits the symptoms sometimes.

Now compare this to a more functional explanation - with or without the scan if you like.
The doctor would explain to you that yes - there is a bulge - but it could be an old one you've had for a year already (without symptoms) - and that the reason you are in pain now is that your brain "has decided" to produce a painful sensation because of some factor that could be biological, social, psychological or all three.

His advice is to keep active, distract yourself as much as possible and adjust your daily life accordingly and check back in one or two weeks if things don't get worse.

Which would you rather pick?
Exactly - option one is simple the better sounding one. Until you had the operation of course and the pain is still there.

That's not to say that all operations are for nothing. But even orthopedic surgeons have started to admit over the past few years that the outcomes weren't that great in cases where the main reason for an operation was pain as a symptom.
Long term studies show that the outcome over the long run is even the same compared to conservative care.
This goes for spinal surgery and other kinds too (think osteoarthritis of the knee).

Pain - like it or not - is in your brain!
It always is - and always will be. It's an emotion like anger, fear, love and all the others. And like all the others it's being put together according to the circumstances you find yourself in.

So if you change the context - you can change the pain - your pain.

Some methods and influencing factors I already have described in my Pain for Dummies Series.

Here are a few more:

- Kinesiotape: How does it work? It's all about low-level cutaneous neural system input - or "grooming" as it's known in primate circles. Have you ever seen chimpanzees grooming each other? That's what kinesiotape does. And if you can honestly say that you wouldn't like to be groomed for a few hours each day you are a liar!

- Feldenkrais: that guy was a genius. Simply brilliant! He recognized that the brain is plastic and likes to learn. That's what happens when you do those exercises - your body learns how to move more efficiently. It's all about feedback and re-programming better motor patterns. When I say Feldenkrais I also mean all the other offshoots his work created: Somatics (faster, shorter - equally cool), Alexander Technique, Rolfing, Yoga, ...
And of course - when you try new movements you have to concentrate a lot - distracting yourself - again.

- Meditation: training how to calm "the mind" - to get the same level of control over your "mental muscles" as over the ones you exercise in the gym.




- Feedback therapies: Mirror Box for CRPS, Phantom Limb Pain and the like. Tactile input for parts of your body you can't see - like our back. And auditory training for tinnitus.

- Redcord: we use this device in our clinic and I have to say it's phenomenal! There simply is no faster way to re-program motor patterns.

- Motor imagery: works. Close your eyes and work out at the same time. Mentally rehearse things that you have to do every day and try to make them more efficient.

- Neuromatrix training: read the blogs - mine, David's and Diane's.

- Educate yourself: the 20th century is over. The expansion of the Internet puts the worlds knowledge at your fingertips (otherwise you wouldn't be reading this!). The more you know about yourself the better off you are.

- Give back: there's nothing like sharing what you have learned or experienced with the rest of the world. By putting your thoughts into words you go over the experiences again - putting them into proper perspective. The only thing you can do wrong is not doing it.

Structure vs. Function - Part II

Let's examine the debate between structuralists and functionalists some more with the ubiquitous ankle sprain for example.

Treatment for such an injury until a few years ago focused mostly on reducing swelling, early weight bearing, .... - and yet the single most important risk factor to suffer from another ankle sprain is still a preceding ankle sprain. The same happens in low back pain (LBP). Your "risk" to suffer from another episode of LBP is greatly enhanced by an episode of LBP in the past.

How come?

Well - the sad truth is that you cannot guarantee joint stability with sheer muscle force - and that was - and unfortunately still is - the theory behind most training regimens. It went something like this: if a joint is injured the best way to provide stability in the future is to exercise the muscles surrounding the joint.

Along come journals like the Journal of Applied Physiology (and others) and show that this simply doesn't work: muscles are way too slow to provide stability.

If you jump on a platform that suddenly tilts under your foot it takes just 10 milliseconds for your ankle to get hurt.

On the other hand muscle takes at least 50 milliseconds to react in the most basic and "primitive" way - with a reflex action.

Let me spell it out for you: muscles contract after (!) the injury has taken place - often making it worse in the process.

Interestingly enough students are taught this in physiology classes - the contraction times I mean. Yet 99.99% fail to make the connection that muscle action isn't sufficient to provide stability.

Lateral thinking rules the day once again. ;-)

You mean to say that training doesn't help at all?

Of course not - but the focus has to be on the timing of the muscle action. Scientists call this the "feed-forward" approach.

Your brain (using the eyes) continually scans your surroundings and the ground in front of you. It then prepares motor patterns based on the visual impression of the surface you are going to step on. In short: your muscles contract way in advance so that they are prepared for the moment when your foot hits the floor. That's when you need the braking force your muscles provide.

It's the same when you try to catch something: your brain computes the path the object travels, factors in gravity (or not - as Alain Berthoz has shown with Space Shuttle Astronauts) - and adjusts your hand muscles so that they are ready to intercept the object. It's all about predicting future events - even when they are just a few milliseconds away.

As for LBP, the same feed-forward mechanism applies: your brain tries to prepare the body for, say - catching (heavy) things by contracting the muscles around your "core". This increases intra-abdominal pressure - thereby enhancing spinal stability and providing a stable "platform" as it where for the extremities. Once you suffer from an episode of LBP this mechanism is put out of action - from then on you use a different motor pattern to control your trunk which isn't up to the demands of everyday life. The deep muscle system of the back stops working and the more superficial muscles take over. They have to exert a lot more force though to keep the trunk rigid during heavy tasks - so they tend to tighten considerably.

On a side note: Rectus Abdominis (the famous "six-pack" muscle) doesn't do anything for increasing intra abdominal pressure. For me it's still the most useless muscle out there.

Only by re-establishing normal motor function - by training coordination and by re-establishing the feed-forward mechanism can you reduce the risk of suffering from another episode of LBP.

Modern rehabilitation has to focus on two things:

one - restoring normal joint play and range of movement (Motion is lotion and creates lots of feedback)

and

two - training the feed-forward mechanism so that the brain becomes better (and a bit faster) at predicting the future, proprioception and reacting faster.

For the first task you are welcome to think in purely structural terms - damaged ligaments, scar tissue formation and so on and so forth.
But for the second one - re-programming motor patterns you have to think like your brain. Sounds strange - I know.

But think about it: your brain has to prepare itself and the body it resides in for a lot of tasks and challenges each and every day. It does so by storing information about previous events (called memories) and building up a huge database about the properties of different objects and surfaces so that it is prepared for the things that lie ahead.

I will come back to this topic with a series about Alain Berthoz book "The Brains Sense of Movement".



How does this picture fit the topic?
Well - some of the same principles are at work here: most people - when the see a fibre optic lamp - just think "lamp".

Me - I see a thousand possibilities. I see movement that can be captured over a period of a few seconds - creating very interesting patterns.

This is what purely structural thinking has lost: it only looks at static structures, snapshots of tissues in different stages (of healing).

Functionalists see change over time, function in a bigger context - and above all a brain that tries to make sense of an outside world and a virtual reality simulation of that world on the inside.

Structure vs. Function - Part I

I guess every field has it's own "vs." debate. They usually last for years without ever coming to a real conclusion.

One would think that by now most people would've noticed that it's not a question of "vs." but of interconnectedness - nature and nurture - not nature vs. nurture.

If you have a gene that makes you more susceptible to developing a certain illness there have to be factors in your environment that activate those genes - otherwise you don't get sick (in that specific way).

The old "vs." debate in Physiotherapy and similar fields is one between structure and function.

There are some who see treating tissues as their main approach - others like me have abandoned those models of thinking (long ago) ;-) and see themselves as "functional therapists" - or neuromodulators - as for example Diane Jacobs does (her excellent blog is here).

Why is there a debate at all?

Well - medicine is still influenced by what scientists/pioneers started when they cut up the first human bodies centuries ago - gross anatomy.

Even today - with all the new techniques that were developed since - medical students start by dissecting bodies and learning about the human animal that way.

What's more - starting with Mixter and Barr in the 30's - every decade more and more and finer and finer structures have been found and are presented as the "pain causing structure". First it was the ruptured disc - now we are down to the vessels that supply the disc and their pressure being elevated causing constricted flow and a sharp rise in pressure. With structural thinking there is just no end in sight - next they are going to focus on molecules being bent out of shape.

And if you haven't realized it by now: those people are dead! Yet medical professionals treat humans that are alive!

You can study the mechanics of flight in this picture - but not flight itself:



Do you see the problem now?

We - as examiners can see muscles and tendons and bones - all clearly discernible - but the Neurosciences haven't found a representation of a single muscle inside the brain yet - they just don't exist from the brains point of view. The brain "thinks" in movements, goals and actions to perform - and uses what's available at the time.

Have you ever seen a runner without legs? With special prosthetics - which are in some ways much better than legs they run just like you and me - yet they have only half (?) of the muscles we think a human being needs to be able to run.

Look at people who had polio - the muscles that weren't affected take over the function of those muscles that are paralyzed.

How does this affect treatment?

Let's look at the example of phantom limb pain: the missing limb hurts, it might be an involuntary clenching or burning pain or whatnot. So the "structural" oriented practitioners started looking for clues in what was left of the extremity. Some of the pain was attributed to the site of the amputation - resulting in another shortening operation, nodules of scar tissue being removed from the stump, the cutting of nerves from the spinal cord to the limb and so on and so forth.

Again the rule of thirds came into play: some got better, some stayed the same, some got worse.

In come the "functionalists" - led by V.S. Ramachandran - building on the work of others of course.

They realized that the cortical map of the amputated limb was still present in the brain - most accessible to study in the somatosensory cortex in the brain. And so called higher centers in the brain act on the information that is contained in those maps - not on what's outside in the real world.

Since pain is produced in the brain Ramachandran speculated that the cause of the pain could lie in the fact that the representation and the visual feedback from the limb didn't match (see Harris Hypothesis for more).

So he gave those amputees visual feedback of an intact limb with a mirror - and the pain vanished quickly.

Those findings have been replicated over and over again - Walter Reed is running a big trial with Iraqi War Veterans to see if mirror treatment is a viable treatment. Traumatic amputations are often much more difficult than "planned" ones.

The sucess rate of this kind of treatment is - at least in small trials well over 90%.

This doesn't mean that the "structuralists" are wrong - but just that they should try to "expand their thinking".

The techniques they use are still useful and are applied by me as well - but the reason why you do something and how you do it is different - helping you in cases when a patient fails to improve.

One kind of therapy that finally started to get around to acknowledging this is the McKenzie method. It originated as a purely mechanical way of treating back pain - but has since then evolved into a method that is able to treat the whole body. The term "derangement" now encompasses all things in a joint that can be "out of whack" - and only cares about if the patient gets better with repeated movement in the preferred direction.
Even large scale trials show that this kind of treatment is very effective. People aren't put into groups based on structural findings - their functional status is all that counts.

I've had discussions with the top people in Germany and the US about openly admitting that they "are only changing neural firing patterns" - not doing anything mechanical with a specific structure - and at least behind closed doors the Germans agreed - the US guru is still not talking to me. ;-)

And this despite the fact that they see how fast people can improve with this method.

Structural thinking is just so easy to grasp and not as "nebulous" as functional thinking - at least to some.