Friday, November 16, 2007

Now back to function... Part II

2. UN-clear metaphor

In Part I, I introduced scenarios related to clear metaphors people use to describe pain. I used "icepick" and "fish hook" examples. When someone says they feel like they have a foreign object lodged somewhere, and it's perfectly obvious they don't, the comparison is at least acceptably clear as metaphor, even if the solution to the pain isn't yet clear.

What about if the metaphor used is not about a foreign object, but a body part that truly does exist inside the body? Suddenly comparisons are much less clear. Suddenly structures are blamed for misbehavior that is actually functional. Suddenly something that feels LIKE a "locked joint", becomes in a patient's mind, or in a therapist's mind, or a doctor's mind, a possibly 'real' locked joint. There are a million of these. Examples are, "I must have a bone out of place." "A muscle is cramped in my foot." "This tendon is too short - look". "I was fine until I lifted that couch, then my (whatever) seized up on me."

These are still metaphors, but now the issues the patient feels in the tissues are not clearly metaphoric at all. In fact, there has been nearly perfect reflection of metaphors like these, a verbal and investigative ping pong match of pain memes and memeplexes going on ever since humans have had pain and human primate social groomers have tried to help.


Slowly it has begun to dawn on some of us who are fascinated by all the little tricks of the brain and the habits it has of setting up simulations of reality, that pain is something of a perception itself. A great example is phantom limb pain. This is pain that an amputee feels vividly and to his or her consternation, in the missing limb. It can't be the limb hurting, because the limb no longer exists.


A representation of the limb does exist, in the brain. A brilliant neuroscientist/brain researcher named V.S. Ramachandran figured out that using a mirror box could help. The patient places the remaining limb in the box in a way that creates an illusion of a missing limb being present, and able to move freely. Even though the patient knows full well it's just a mirror image, moving freely and painlessly, some important part of the visual cortex actually will record this information and send it around the brain in such a way that pain is relieved in the "missing limb", the phantom of the missing limb, the virtual body part, the representational map of the part located in the brain. It's as if the brain thinks to itself, hmm, I must have made a mistake. It looks like that part can move ok.. Alrighty then, I'll take out the pain signal.

It gets even more strange - it turns out we all have these maps - everyone has them. And we all can feel pain in them, just as amputees do. Ready for more strangeness? Pain is usually in the brain map part instead of in the actual part. I know - this is where "what everyone knows" bumps into new science. Such apparent heresy! But not so strange if you accept the idea that the brain is a great big simulation producer. It can make you have a pain in a part that is not at all "damaged", just because it senses a threat to that part. Yes, you read that right. Nothing has to have happened to the part for the brain to make a pain in it. From my blogpost of September 4th, "Rhythms of the Brain" by György Buzsáki:
The short punch line of this book is that brains are foretelling devices and their predictive powers emerge from the various rhythms they perpetually generate. At the same time, brain activity can be tuned to become an ideal observer of the environment, due to an organized system of rhythms.

I really want you to know I did not make this up - György Buzsáki wrote an entire book about how this is not just possible but likely.

What can decrease pain? Helping the brain sort, refine, redraw its maps. How? Create an illusion for the brain in regular 4-limbed people in pain that is as powerful as the mirror box is for phantom limb pain. How? Well, movement is the key here. The brain needs to perceive some kind of movement before it can get off the square it is stuck on, pain-wise.

One can create a kinesthetic illusion of movement, through skin stretch. Simon Gandevia is the researcher who came up with this while studying cutaneous receptors. He is a lot less famous than Ramachandran is, but no less important to those of us who work with new ideas on how to pare back erroneous metaphor in our own thinking about pain. True, Simon Gandevia hasn't linked his own research yet to pain relief itself, specifically, but he has provided a huge clue. Putting this clue together with Patrick Wall's idea that pain is a "need state", and that pain relief follows a "consummatory movement", and bearing in mind the success of mirror therapy for pain in limb representations, is it really that hard to draw a line connecting the dots? Treating people who still have all their parts is much easier because you don't need a mirror, you just need to get on their skin and give their brain a movement illusion.

To me, this cuts through all the confusing metaphoric mesodermal tissue based wild goose chases that practitioners go on, led originally by convincing descriptions of pain given to them by patients, which they then go on and foist on other patients, and all of which becomes some version of gravely mistaken treatment orthodoxy. I am fond of saying three things to patients on their first visit:
1. There are people who have things on x-rays like degeneration (etc.) who don't have any pain
2. There are people who have pain, and have no x-ray changes
3. Pain and x-rays (or, pain and body weight, pain and posture, pain and... [etc.]) don't necessarily have anything to do with each other

(Truth is, I'm haunted a bit by all the years I worked as a PT, diligently and inadvertently contributing to peoples' pain experience by choosing wrong words, like, "looks like a disc problem", "Sudek's Atrophy? You'll need to wear this brace to keep your fingers from curling into your palm", "This looks like a tendon rupture", etc etc... I'm haunted by a past filled with thousands of faces of patients who intersected with my life, in pain, with ordinary nervous systems and intact tissue, looking at me as some sort of keyholder of relief for them, me having official human primate social grooming status and license but no key, no clue!- to how to really help them at all, other than temporary accompaniment and a set of protocols on how to get them to move anyway, even if it hurt, social manipulation/motivation. Cheer leader stuff. It makes me cringe nowadays - if I were in a patient's shoes I would want to shoot some kid fresh out of school who had the audacity to think she knew the first thing about what my brain and body were going through. But apparent sincerity and earnestness kept me alive, I suppose... Plus, to be fair to my former self, there was not all this nice research available back then, in the 70's. There is no excuse for continuation of perpetuation of inappropriate metaphor in my profession (or the medical profession) anymore, other than pure ignorance/being too busy to read/relying on the schools to have taught what is necessary to know to do the job. The schools are only just learning about this stuff themselves! It'll be awhile more before they figure out how to do the requisite "knowledge translation".)

Certainly there will be some hips that still need replacing and some knees, and so on, but the pain felt in those parts which have been sacrificed might not be relieved by the sacrifice, might not have been from those 'parts' in the first place!

Does it not make more sense to deal with pain first, provide the simulating brain with a movement illusion, see if it really is cranking out pain for no particularly good reason? If the pain goes away, great! Show the patient a few exercises to keep pain at bay. Another knee or hip or (insert name of structure) saved from sacrifice. If pain doesn't go away/stay away, then think about replacing the part.

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