Hope to peep in a bit more often again.
“Structuralism” is the excessive focus in the physical therapies on postural and biomechanical factors in pain problems. The basic problem with structuralism is that biomechanical factors correlate poorly with pain problems.
Most doctors and therapists have a love affair with “structural” explanations for practically everything that hurts. It pervades musculoskeletal health care like a bad smell. A structural explanation for injury and chronic pain blames the problem essentially on being crooked or deformed or dysfunctional in some way: a short leg, a tight ITB, a crooked kneecap, or any one of a hundred other popular biomechanical bogeymen.
And I have seen that structuralism infects both alternative and mainstream health care: surgeons and injury rehabilitation specialists are just as obsessed with structural explanations as chiropractors. Perhaps they are even more so, doing countless x-rays and MRIs and exhaustive physical exams in the quest to diagnose your deformity or dysfunction, and endless surgeries and therapeutic exercises to correct or compensate for your deficiencies. They also do thousands of scientific studies in the effort to validate all of this, and apparently just ignore their own results, which almost invariably show the same disappointing fact:
Structural problems correlate poorly with symptoms.
it clinically matters little what structural factors may be present in a given joint if tissue homeostasis is safely achieved and maintained. I believe the evidence shows that most bio-“mechanical” problems are much less important than is routinely imagined. To understand injuries and pain problems and to recover from them more effectively, both patients and professionals need to stop trying to think of the body as a machine that breaks down, and start thinking more in terms of squishy, messy physiology, especially neurology and biochemistry.
Many times I’ve listened to patients, almost literally brainwashed by structuralists, seriously saying that their severe pain is the consequence of an “alignment” problem so subtle that you’d be hard pressed to detect the deviation with a microscope. Nobody older than thirty would be able to walk if such trivial defects could really wreak that kind of havoc. People who have terrible body pain problems often have excellent posture, good ergonomics, and healthy joints — bodies that are basically in great condition. Meanwhile, people with perfectly obvious biomechanical problems — everything from significant scoliosis to obesity — are doing just fine.
- My favourite direct evidence — not the best, but my favourite — has always been the simple leg length study published way back in 1984, in the venerable British medical journal Lancet. That paper that showed that leg length differences were unrelated to back pain — no correlation even, let alone a causal relationship.
- The fear of an excessive curve in the low back, AKA the pelvic tilt myth, has spawned countless back pain “cures” based on stretching and strengthening to try to flatten it out a little, with the (coincidental I’m sure) bonus of flattening bellies at the same time. This is a well-studied question, and a 2008 systematic review of more than 50 studies found no association between measurements of spinal curves and pain. If there is any connection, it’s a weak one.
- Surely narrowing of the spinal canal is always painful? Perhaps not. Cranking up the counter-intuitiveness another notch, scientists found in 2006 that a structural problem that everyone previously assumed to always be painful — even I thought so! — turns out not to be. Spinal stenosis has always been regarded as an inevitable cause of back pain, but the Archives of Physical Medicine & Rehabilitation has showed clearly that it often does not cause pain after all.
Indeed, the foot bone really is connected to the leg bone, and so on. That these kinds of more complex biomechanical relationships exist is not in question — they do. The trouble is that they are hopelessly complex, effectively impossible to interpret reliably, extremely difficult to treat … and, above all, simply not all that important.
Recall that we have already demonstrated that even simple biomechanical relationships do not correlate well with pain. A narrow spinal canal does not predict stenotic back pain. Many people with ITB syndrome do not have a tight ITB. And so on. Even the most direct relationships tend to defy common sense. The relationships exist, yes, but it turns out that they are fiendishly hard to understand.
Every time you add another link in the chain of reasoning between a symptom and its proposed cause, you increase the complexity and the chance of error exponentially. Considering that therapists often cannot even agree on the existence or clinical significance of a single biomechanical factor, what are the odds that they are going to agree on the causal relationships between three or more of them?
Of course, biomechanical factors are relevant to some injuries and pain problems. Ask anyone who has had a ruptured tendon. Structuralism is, by the definition I’ve given it, an excessive preoccupation with biomechanical factors. Biomechanics do matter sometimes. Some biomechanical bogeymen truly are scary, and there are times for a structural diagnosis, and a structural solution. Some problems are clearly more “mechanical” in nature than others. Yet there is no doubt in my mind that the evidence leads us away from getting our knickers in a collective knot over most of the popular structuralist theories.
If not structure, then what? Neurology and homeostasis. The body is assuredly not just a complicated machine. Similarly, therapists must get past mechanics. Joints may be like hinges in a superficial way, but they are not hinges, work nothing like hinges, and fail nothing like hinges.
In general, it has become clear that the “behaviour” and condition of individual muscles is mostly trivial compared to the potent role of the central nervous system as the dictator of almost everything about both function and sensation. In short, it’s not “muscle imbalance” that makes people slump and hurt — it’s a brain thing, and poor posture is an effect instead of a cause
Posture is only one of many hypothetical factors that contribute to pain problems, and in many cases it probably isn’t contributing at all. This is obvious from a simple observation: there are a lot of people with perfectly good posture who are in terrible pain, and also many people with terrible posture but no pain. janky biomechanics just generally don’t match up very well with chronic pain.
I’m skeptical about posture as the direct cause of anything. The range of asymmetry that people can tolerate is probably quite wide, highly variable, and generally narrower with age, but the average healthy person can probably easily tolerate “poor posture” with no problem. And if poor posture can’t really hurt a healthy person, it’s not much of a demon, is it?
On the other hand, more vulnerable people, people who get pain from trivial postural strain do not have a posture problem so much as they have a pain problem. A vulnerability. The greater the vulnerability, the more it’s about the vulnerability and not the posture — awkward postures are just another thing that triggers pain (even if we are quite careful). It doesn’t really seem like posture is what needs troubleshooting there.
Pain is all about your brain’s assessment of safety. Unsafe things hurt. If your brain thinks you’re safe, pain goes down. A confident and happy brain amplifies pain signals less than an anxious, miserable brain. As science advances and mind-body perspectives on health and healing become more sophisticated and practical, we understand that pain problems are powerfully mediated by stress, self-limiting behaviours, and “emotional constipation.”
If your brain thinks you’re safe, pain goes down — and pleasure feels safe. So be “nice” to your CNS in every way that you can think of. Make your life — or a joint — feel safer, gentler, more pleasant. Do it in general ways (soak the whole system in a hot tub), but also more specifically: pleasantly stroke a sore knee, give a screaming shoulder the “comfort” of a sling for a while, or cautiously but thoroughly move a troubled joint to demonstrate to your brain that it’s okay.