Why the “scare quotes” around “rehab”? According to Merriam Webster, rehabilitation is most often defined as, “to bring (someone or something) back to a normal, healthy condition.” This would hold true in the traditional model of physical therapy care that I referenced earlier: B + C → A. It is clear that, on one hand, there are far too many variables to make this an accurate account, but I want to explore the notion of physical therapy, even in a complex system, getting a patient ‘back to where they were’ before their injury.
Very often in these networks, you’ve got all types of feedback loops and they interact, so there is intense complexity to these networks and the loops; that is one of the reasons why systems that are (locally) easy to understand become very complicated when you look across an entire network. We also need to differentiate between positive feedback and negative feedback. In positive feedback, there may be multiple equilibria. We need to distinguish that from negative feedback, which closes the gap between the actual and the desired; that has a single equilibrium point.
The initial primary complaint of a patient is very rarely of a specific dysfunction (i.e. something is wrong with my L3-L4 facet). No, their primary complaint is more often related to their general dysfunction. They walk in and say, “My back hurts.” For decades, traditional care involved the therapist using a complicated reasoning model to discover an underlying dysfunction that would predictably respond to intervention, bringing the offending structure back into equilibrium. Again, sometimes it worked, often it did not. This, is because even if the therapist was able to restore health to a tissue or optimal movement to the perceived offending structure, they were working from a false premise.
Often, in complex systems, we assume an equilibrium point and we make wrong assumptions. We assume that (as in a simple mechanistic system, with a single equilibrium point) that if we apply the right amount of correction at the right time, it will actually go back to its equilibrium…We cannot do that with things that are complex.
While the bones, joints, muscles, ligaments, fascia (etc) are all parts of an admittedly complicated mechanical system, they are but pieces of a marionette**. It is not the marionette that feels, senses, emotes and motor plans, but instead the puppeteer. It is the puppeteer’s own complex nervous system that brings the puppet to life. It is the nervous system of the puppeteer that brings about the marionette’s expression, its movement. Most importantly, it is always the puppeteer – never the marionette – that feels pain. All that the puppeteer is, with all of his complexity – all of his experiences since he was born, his expectations, his fears, his motivations, his desires – is screaming in pain behind the curtain while the therapist provides treatment to a puppet on a stage.
Meanwhile, the therapist is trying to “get the patient back” to how they were before – to bring the patient’s experience back into equilibrium. This, however, can never be the case.
You cannot go back to what existed in the past. There is no reestablishing a position, because the system – by exploring new alternatives and evolving – will attain a different state. One equilibrium shifts, however, there are multiple equilibria at one time, not a single one. That is the key thing here. Or there may be no equilibrium at all; the system might be in a state of constant change. In traditional science, you have a formula. For example, if you fire a cannon ball, you can predict exactly where it is going to land in when it is going to land. In most of the systems we call complex, we can’t do that with any degree of certainty.
While the therapist has extensive knowledge of biomechanics and is often indispensable in the helping the patient regain once lost mobility and strength, the primary job of the physical therapist is to guide a nervous system in such a way that it is able to discover how to move comfortably and efficiently once again, using neural circuitry in a way that it has never done before, reshaping the patients neural pathways, creating new neurotags. What we do as therapists is more wonderful than we give ourselves credit for…when done right, it is a beautiful thing – even though we don’t have control.
Tomorrow – Where do we go from here?
**I need to attribute this metaphor to Diane Jacobs, PT. I thought I had come up with it by myself, but after some research, I discovered I had read something similar last year. I felt as if I had slept on Ziggy bedsheets (Seinfeld reference)