Almost everyone who has ever sought professional help for a stubborn pain in their body has been told that they are deformed and fragile, that the root cause is some kind of “mechanical” glitch — not in such insensitive words, exactly, but that’s the take-home message. Just as acupuncturists can be counted on to blame most problems on a blockage of qi, freelance manual therapists in particular1 tend to blame pain on “structural” problems, such as:
… and a long list of more technical-sounding problems such as tibial torsions, steep Q-angles, and many more absurd examples.2 Some of these may well be valid. For instance, I have a minor but definite deformity in my right foot that has caused me some pain.3 But the scientific evidence clearly shows that the importance of most bio-“mechanical” problems has been greatly exaggerated. There are (at least) five major problems with these kinds of diagnoses:
- Not only are structural explanations for injury and poor recovery generally unsupported by any scientific evidence, the last 25 years of research results mostly undermines them, often impressively.
- Professionals can rarely agree on them (poor diagnostic reliability).
- Most structural diagnoses are difficult or impossible to do anything about even if you can agree on them in the first place.
- Patients are often given the alarming idea that the slightest crookedness is “serious” (and may require expensive therapy to correct).
- Finally, biomechanics is obscuring more useful, new ways of looking at failed rehab and chronic pain.
To understand injuries and pain problems and to recover from them more effectively, both patients and professionals need to stop trying
“Structuralism” is my own term for the excessive focus — not any focus, just excessive focus — on postural and biomechanical factors in pain problems — the biomechanical bogeymen, the physical quirks that people fear as sources of pain and injury. The basic idea is that anything abnormal causes stress on tissue, “wear and tear,” and then eventually pain. Something like a short leg is assumed to lead inexorably to suffering.
In its most simplistic and absurd forms, structuralism fixates on just one or two biomechanical factors as the wellspring of most or all pain. Structuralism this extreme is surprisingly common, almost impossible to avoid. Here’s one example: I know of a massage therapist who earnestly believes that the stability of one tiny bone — the cuboid bone, a foot bone the size of a sugar cube — is the key to all pain and its relief. That may be an extreme example, but it’s actually identical in spirit to a much more popular one: Morton’s Toe, a condition in which the big toe is unusually short, is often blamed for widespread body pain.9
These kinds of theories about the causes of pain get even stranger than that. I know of another professional who believes that he has identified the source of “all pain,” namely a consistent pattern of postural dysfunction that is caused by Coriolis force, of all things — the effect of the spin of the earth on currents in the ocean and atmosphere, the cause of storm spin (but not of the direction of water circling a drain — that’s a myth, it doesn’t work on small scales). He told me, with a straight face, that this pattern of dysfunction “should be the opposite Down Under”!11
These are silly ideas! Flat-out nonsense.
But structuralism definitely isn’t just for health professionals with the weakest and strangest ideas. Many orthopaedic surgeons, physiatrists, and sports medicine specialists are also keen structuralists. Most chiropractors are structuralists, almost by definition. The great majority of physical therapists and massage therapists are inclined to structuralism. The Functional Movement Screen is an extremely conventional, popular new method of “effortlessly identifying asymmetries and limitations”12 which is routinely used (and abused) to justify treatment — a perfect example of structuralism right in the middle of the mainstream.
These professionals are not all united, and subscribe to many different flavours of structuralism. For instance, many doctors disdain chiropractic structuralism — but in place of poorly defined chiropractic “intervertebral subluxations,” physicians ironically put forward their own more scientifically respectable biomechanical factors. But while doctorly structuralism is less anti-scientific in tone and substance than a lot of chiropractic philosophy, unfortunately that doesn’t necessarily make it any more correct. Just as the manual therapies are infested with all kinds of biomechanically inspired treatments, so to there has been an epidemic of dubious orthopedic surgeries to “correct” every imaginable kind of structural problem: different expressions of structuralism.
I will show that most structuralism is barking up the wrong tree. This isn’t a scholarly article, but it is heavily referenced — there are plenty of citations to credible and interesting scientific research, linked and summarized.
A patient once gravely informed me, as if sharing a dangerous secret, that a chiropractor had predicted his back pain by identifying a minor leg length difference ten years earlier. The prediction was a warning: get your short leg fixed, or else you’ll be laid low by low back pain for sure!
Such a prediction is about as insightful as predicting death, taxes, or the rising of the sun. Back pain is one of the most common afflictions in the modern world. An impressive 90% of all people will have an episode of acute back pain at some point in their lives … whether they have a “short leg” or not.
“The warning” is the most common way that structuralism can do harm. It is often a part of the sales pitch for a structural diagnosis. It simultaneously offers the client a pleasingly simplistic explanation for their pain, and yet it also manages to frighten patients into paying for therapy for the wrong reasons. Much worse, and ironically, it can probably frighten them right into real pain or pain chronicity, in some cases, via a nocebo effect — the opposite of a placebo.1314 The prevalence of such scare tactics is why I originally coined the term “biomechanical bogeymen.”
I remember how annoyed I was at the fact that [this Rolfer] thought he “knew” what was wrong. He told me to stop walking like an old man — like I was just assuming some contorted posture when I could be standing straight and tall if I just decided to, like I had become that way because I had started to think of myself as an old man and so became one. He literally believed that! Fortunately, I didn’t.
reader Harry M
Most of the bogeymen exist so that freelancer therapists have something to therapize, a problem to solve for a fee. With low to zero diagnostic reliability, diagnoses like “shoulder dyskinesia” — fancy talk for bad shoulder movement — are clinically trivial and have more to do with sounding good than actually knowing anything helpful, so a professional can stare at your shoulder for a while and wisely declare, “Well, there’s your problem,” as though it were obvious. To an expert.
And if the therapist can’t identify a problem to solve, why even show up? That’s what most people are paying for. The pressure to cough up an easily understood premise for therapy is immense.
This is an extremely cynical viewpoint, of course, but I cannot overstate how common it is for therapists to make the entire treatment encounter revolve around the idea of identifying and exorcizing structural flaws, and how strongly and literally they buy into that kind of therapy.15
For instance, an acquaintance of mine described in reverential detail just such an appointment. After a minor accident, she had nearly normal shoulder movement and no shoulder pain, but was delighted to have paid for an osteopath to identify and fix an allegedly “dislocated” shoulder. There was no real problem to solve… but that freelancer therapist identified one anyway, claimed to solve it, and the customer was not just satisfied but impressed. My acquaintance was actually excited to show me her new “improved” shoulder ROM. That’s how potent a sales pitch the structuralist diagnosis can be.
Countless times I’ve listened to patients tell stories about such overtly nonsensical biomechanical diagnoses, almost brainwashed by structuralists.16 And if someone without pain is satisfied with that, imagine how shut-up-and-take-my-money people can get when given a tidy mechanistic explanation for serious chronic pain. Promised a fix, they will eagerly believe that their severe pain is the consequence of a subtle “alignment” problem — often so subtle that you literally couldn’t measure it with a goniometer or get any two therapists to spot it.
Nobody older than thirty would be able to walk if such trivial defects could really wreak such havoc.
People who have terrible body pain problems often have perfect posture and good ergonomics (low postural stress), and healthy joints — bodies that are basically in great condition. Meanwhile, many people with perfectly obvious biomechanical problems — everything from significant scoliosis to obesity — are doing just fine, thank you very much. For instance, a 2012 study clearly showed that severity of people’s pain simply did not match up with the severity of their joint degeneration.17 This inconsistency is so glaring that it’s puzzling that so many professionals seem to ignore it. Why? How can they miss it?
Simple: unfortunately, it pays to miss it. It pays to have structural villians to go after. It pays to pathologize.
Irregularity is to be expected in any biological form. Body parts are not interchangeable legos or Ikea furniture pieces made by factory molds. Wonkiness and asymmetry are part of the plan.
~ Playing With Movement, by Todd Hargrove, p. 169
Clinicians fail to notice the inconsistency because they think they need “something to fix” so that they can get paid for fixing it. If the definition of “normal” was widened — as it should be, because there’s really an incredible range of healthy anatomy18 — then there would be a lot less to fix. There would be fewer “problems” to diagnose, less to seem wise and knowing about, and less therapy to recommend to the customer. Natural biomechanical diversity undermines clinical mojo.
So it’s not in the best interests of therapists to “normalize” patients and describe their anatomical quirks as harmless, but quite the opposite! It’s better for egos and incomes to define “normal” narrowly, and place the blame for pain on anything that sticks out — literally or figuratively — giving naive customers the impression of cleverness for identifying the root cause of the trouble.
It is difficult to get a man to understand something when his job depends on not understanding it.
~ Upton Sinclair
The Upton quote could not possibly be more applicable. Adapted slightly: It is difficult to get a therapist to understand that structural abnormality is rarely meaningful when his job depends on ignoring this data and actually emphasizing structure.
And of course there’s also just good ol’ confirmation bias. Once you start mentally leaning towards the idea of asymmetries as a major cause of pain, you start noticing and emphasizing only the cases that seem to confirm that expectation … and ignoring the ones that contradict it. Health care is so full of puzzles that it’s effortless to write off anything that doesn’t confirm your bias as an inexplicable oddity — you can even claim humility, shrug, confess “I don’t know,” even as you conveniently dismiss data that could have taught you something.
The basic problem with structuralism is that biomechanical factors have surprisingly little to do with pain problems. The two things correlate poorly. But structuralism is deeply embedded in our cultural consciousness, and we cling to the idea that aligned and symmetrical must be the best way to be, and we suffer in proportion to our deviations from that diagram. That equation makes intuitive sense to us, and we’re just not going to give it up easily!
I enjoy “pathologizing” posture. It gives me a sense of purpose.
~ Les Glennie, Registered Massage Therapist (yes, tongue-in-cheek)
Don’t take my word for it, for goodness’ sake. There is a lot of hard evidence and the most expert possible opinions to back me up. Nor is it an extreme position to defend: I do not need to convince you that both baby and bathwater should be thrown out together. My work here is done if I can just convince you that there is reasonable doubt that biomechanics are a major factor in most pain.
Structuralism has been shunned by many medical researchers and experts.
For instance, San Francisco orthopaedic surgeon Dr. Scott Dye has written eloquently about how ill-advised structuralism is when it comes to knee pain.19 Eyal Lederman, a UK osteopath, wrote a particularly persuasive article criticizing the postural-structural-biomechanical model20 — an article much like this one, but much more academic and technical. (For balance, I will also cite the extensive rebuttals to that article published in the Journal of Bodywork & Movement Therapies in 2011.21) Foot, shoe, and orthotics expert Benno Nigg wrote an entire book22 about how poorly structuralism has stood up over time. In a 2011 paper, “The Modernisation of Manipulative Therapy,”23 Australian physiotherapist Max Zusman writes:
Research indicates that, despite physiotherapists’ comprehensive training in the basic sciences, manipulative (currently “musculoskeletal”) therapy is still dominated in the clinical setting by its original, now obsolete, structure-based “bio-medical” model.24
Back pain experts Drs. Richard Deyo25 and Nickolai Bogduk26 have virtually devoted their careers to teaching doctors not to overestimate the importance of biomechanical factors in back pain. Bogduk writes concisely: “‘Degenerative disc disease’ conveys to patients that they are disintegrating, which they are not. Moreover, disc degeneration, spondylosis and spinal osteoarthrosis correlate poorly with pain and may be totally asymptomatic.”
Dr. John Sarno’s career has also been about debunking structuralism in back pain.27 In 1984, he first wrote:
There is probably no other medical condition which is treated in so many different ways and by such a variety of practitioners as back pain. Though the conclusion may be uncomfortable, the medical community must bear the responsibility for this, for is has been distressingly narrow in its approach to the problem. It has been trapped by a diagnostic bias of ancient vintage and, most uncharacteristically, has uncritically accepted an unproven concept, that structural abnormalities are the cause of back pain.
~ Mind Over Back Pain, by John Sarno, p. 112
Neurology and neuropathy, homeostasis, subtle pathology, biological vulnerability. There are all kinds of tissue issues that may have little or nothing to do with structure, aligment, and biomechanics at all.
“Who says” about the alternatives to structuralism as a paradigm is such a long list that it cannot be meaningfully narrowed down. You could include any researcher who has ever identified anything that goes wrong and causes trouble and pain that is not structural or biomechanical in nature. For instance, in 2011, biologist Paul Kubes published a great example of fascinating evidence that inflammation may become chronic due to a glitch in human immune systems.28 Or consider the Japanese researchers who have probably finally explained how exercise soreness works (basically “neurological growing pains”).29 Or look at Robert Sapolsky’s entire body of work the subject of the biology of stress,30 and its clinical relevance to anxiety, depression, insomnia, and chronic pain. Or Dr. Michael Holick’s crusading on the topic of vitamin D deficiency (even if it’s not clear that he’s right, it’s an interesting possibility and we’d be foolish to ignore it). Or the major contributions to the science of fibromyalgia by Drs. Fred Wolfe and Daniel Clauw. Or the other Woolf, Dr. Clifford Woolf, who has contributed so much to our understanding of sensitization.
And so on and on. There are many potential mechanisms of pain that have little or nothing to do with posture, alignment, and structure — and an army of researchers and other experts who have been pushing beyond that very limited view of how pain works. But I’ll continue with a couple more important examples…
Sassy Aussie pain researcher Dr. Lorimer Moseley has been doing excellent research and “outreach” on this topic for years now, constantly encouraging clinicians to understand pain not as an inevitable consequence of biomechanical stresses and tissue trauma, but as an output of the brain strongly affected by many considerations — many of which have nothing to do with issues in the tissues.31 In particular, “The evidence that tissue pathology does not explain chronic pain is overwhelming (e.g., in back pain, neck pain, and knee osteoarthritis).”32 — and if pain chronicity can’t even be explained by tissue pathology in these common conditions, it’s not very likely that subtle biomechanics can fill in that blank. This perspective has been spreading like wildfire.33
Dr. Janet Travell, Dr. David Simons and Dr. Siegfried Mense all made significant scientific contributions toward understanding the more subtle and complex alternatives to structuralism, especially the ways that muscle might hurt more or less “spontaneously” — due to neurological and/or metabolic dysfunction — perhaps causing a lot of the chronic pain that would normally be attributed to biomechanical bogeymen. Simons in particular wrote extensively and passionately about the neglect of muscle as a source of pain:
Muscle is an orphan organ. No medical speciality claims it. As a consequence, no medical specialty is concerned with promoting funded research into the muscular causes of pain, and medical students and physical therapists rarely receive adequate primary training in how to recognize and treat myofascial trigger points.34
In order to spot a physical flaw that needs to be corrected, one must begin by having a reliable measure of whether or not it is actually problematic in the first place.
~ Tumminello et al, 2017, Personal Training Quarterly
Many key scientific studies over the years have undermined major structuralist assumptions. Some of the evidence is direct. Some is indirect, or “circumstantial,” as a criminal lawyer would put it. There is a strong pattern of all kinds of evidence converging on the same conclusion: structuralism does not produce effective therapies. It does not “deliver the goods.”35
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. It showed that leg length differences were unrelated to back pain — no correlation even, let alone a causal relationship.36 And then there’s the fact that minor differences cannot even be reliably diagnosed in the first place37 — a standard problem with alleged structural problems.
Wear and tear? Not so much. One of the most deeply held beliefs in musculoskeletal medicine is that osteoarthritis is a “wear and tear” condition — that joints break down under the onslaught of gravity and use. This fundamentally mechanical view of arthritis directly suggests that the longer we live and the heavier we are, the more likely we are to have joint trouble. But we know that knee osteoarthritis prevalence has doubled in the 20th Century independent of age and weight.38 This destroys the wear-and-tear story. Something else is going on. We need to be looking at neurology and immunology (inflammation).
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.39 If there is any connection, it’s a weak one.
An excellent example is a failure of the Functional Movement Screen to detect actual recent injuries, let alone any subtle or specific biomechanical risk factors for injury. As mentioned in the introduction, FMS is a set of physical tests intended to “identify asymmetries and limitations,” based on the assumption that they are a problem — which is classic structuralism. A 2011 study in the International Journal of Sports Physical Therapy found that FMS test results didn’t change in people who had actually been injured within the last six months.40 If a test can’t detect the effect of recent injury on the body, or the risk of factors that led to it, it probably can’t detect future injuries either, and the structural assumption at the heart of FMS is therefore rather dubious. I examine more evidence like this in The Functional Movement Screen (FMS); for a more thorough and academic analysis, see “The Corrective Exercise Trap”.41
The neck is a popular place for biomechanical bogeyman, but in 2007 Grob et al published findings in the European Spine Journal that abnormal neck curvatures do not have any connection with neck pain.42
Or the shoulder? “Shoulder dyskinesis” — fancy talk for bad shoulder movement — is a popular biomechanical bogeyman in this area, but there’s definitely no smoking gun evidence that funky shoulder movement leads inexorably to pain. A 2013 review in the British Journal of Sports Medicine concluded “no physical examination test of the scapula was found to be useful in differentially diagnosing pathologies of the shoulder.”43 (Funny story about that citation, too.44) A 2017 British Journal of Sports Medicine paper loudly declared in its title that “scapular dyskinesis increases the risk of future shoulder pain by 43% in asymptomatic athletes.” Yikes? But it was a bizarrely misleading headline.45
Perhaps the knee? A bizarre and amazing study published in the New England Journal of Medicine in 2002 showed that a placebo for knee osteoarthritis is just as good as real surgery.46 A more “mechanical” problem than rough knee cartilage can hardly be imagined, yet 150 people who received a sham surgery recovered just as well as people who actually got their cartilage polished. That’s a crushing blow to structuralism! Except maybe this? A 2010 review of risk factors for the development of knee arthritis (after the loss of meniscal tissues) mostly eliminated “poor knee alignment” as a factor.47 Surely poor alignment would definitely spell trouble? That’s a common assumption! But not a safe one.
Numerous MRI studies of the back over the years have shown just terrible correlation between structural problems and back pain.48 Time after time, you find that people with low back pain have no mechanical problems, and people with mechanical problems have no low back pain.
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.49
Hip pain is rarely caused by arthritis… even when the hip joint is clearly arthritic. Most people with signs of arthritis (on X-ray) do not have any pain, and most people who have hip pain do not have arthritis.50 Most hip pain is … something else.
Poor pain-degeneration correlation in animals, too! Here’s an interesting perspective from veterinarian Johnny Bat-Yonatan on canine hip dysplasia, an arthritic condition common in big breeds like Labrador retrievers, German shepherds, and rottweilers:
It’s a horrendous thing that often leads to the animal having to be euthanised, but the highly specialised grading of hip dysplasia doesn’t correlate directly with mobility and life quality. You have great x-rays of animals that can barely walk, and horrendous hips in dogs that don’t display any pain. X-rays sometimes tell a story, other times they’re a footnote. We learn early that we need to treat the animal, not the radiograph.
“Treat the animal, not the radiograph.” Nicely put, and equally apt for pets and their humans. We’re all animals! For more information, see Canine Hip Dysplasia, by Wendy Brooks, DVM, DipABVP.
We are all amazingly capable of adapting to biomechanical challenges.
Fang in your throat? The styloid bone at the back of the throat looks like the fang of a sabre-toothed squirrel. It can get too long and start to bother the sensitive anatomy around the tip (Eagle Syndrome). Except, surprisingly, most people with elongated styloids are just fine. Clearly, styloid length is not a hazard in itself — something else has to be wrong.51
If spinal instability were painful, surely stabilizing it would help? But a 2009 study showed that “stabilizing” fractured vertebrae by injecting bone cement doesn’t actually aid the recovery — at all!52 If such a straightforward method of stabilization doesn’t work, it’s pretty hard to make the case that instability could have been much of an issue in the first place.
Sports injuries aetiology investigations have assumed a reductionist view in which a phenomenon has been simplified into units and analysed as the sum of its basic parts and causality has been seen in a linear and unidirectional way. This reductionist approach relies on correlation and regression analyses and, despite the vast effort to predict sports injuries, it has been limited in its ability to successfully identify predictive factors.
~ Bittencourt et al, 2016, British Journal of Sports Medicine53
More running risk factors: Pronation is only the most famous of a whole posse of similar biomechanical quirks that supposedly plague runners, including some already mentioned above. Most attempts to confirm these have failed. In 2004, Devan et al published in the Journal of Athletic Training that they couldn’t find any connection between knee injuries like iliotibial band syndrome and patellofemoral syndrome and any of the mechanical “usual suspects” that are blamed for those conditions.54 Another paper that year reported “no evidence that static biomechanical alignment measurements of the lower limbs are related to lower limb injury except patellofemoral pain syndrome.”55 In 2009, Ferber et al concluded “there is no definitive link between atypical foot mechanics and running injury mechanisms.” A 2016 study in the Eur J Sport Sci “did not find significant associations.”56 This is not to say that there are no structural risk factors for running injuries — there is some evidence pointing that way. But whatever associations there may be are clearly not very clear.
Core strength is still assumed to be important by nearly every professional and patient,57 and yet it has been thoroughly debunked by one experiment after another for twenty years now. The “corset hypothesis,” a popular justification for core training, is nonsense.58 No kind of core training has any special power over back pain. It can’t produce better results than any other kind of therapeutic exercise, and it does not reduce injury rates. This is all covered in much greater detail in my low back pain book.
One of my favourite examples of core strength research is a 2010 study of more than 1,100 soldiers which found that specialized, “precise” core strengthening did little to improve rates of low back pain (or any other injury) compared to good old-fashioned sit-ups.59 Meanwhile, many other studies show that no kind of core strengthening is important.60
A large 2011 study of massage therapy for low back pain61 tested the effectiveness of a “structural” style of massage consisting of a blend of popular techniques and treatment approaches based on common structuralist assumptions. Massage therapists are prone to believing that “the right moves” will have a more profound therapeutic effect.
Moderately-trained therapists with more than five years of experience provided about 130 patients with 10 hours of this kind of massage. They also gave ordinary relaxation (Swedish) massage to another 130 patients. The effects on back pain of these two approaches were carefully measured over an entire year. The results were revealing: there was “no clinically meaningful difference between relaxation and structural massage” whatsoever! That is quite an embarrassing outcome for techniques that are routinely touted as “advanced.” If structuralism were a good basis for massage technique, shouldn’t it have produced impressively superior results?
Muscle “imbalances” are one of the classic biomechanical bogeymen. Asymmetrically under and overdeveloped muscles are nearly always demonized as sources of stress and strain that are inherently painful and boost the risk of injury. There are many examples of uneven muscle mass in serious athletes, but none are confirmed causes of pain or risk factors for injury, like the imbalanced back muscles of pro footballers.62 This is exactly the opposite of what any good structuralist would predict.63
Asymmetric atrophy is even easier to demonize, but there’s good evidence that it is both common and harmless in tennis players.64 It would be a mistake for a massage therapist to compare sides in such athletes and start trying to “restore balance,” but I suspect most massage therapists would make that mistake.
A blow to the importance of muscle “balance” — symmetrical muscle mass and strength — was delivered by the British Journal of Sports Medicine in 2010.
My personal experience in studying this subject for the last several years is that I can hardly look anything up anymore without finding more evidence that structuralism is a lousy way of explaining people’s pain.
Patient complaints that originate in the musculoskeletal system usually have multiple causes responsible for the total picture.
An important part of my case against structuralism is that it’s not absolutist. It would be impossible to argue that structure “never” matters, because that’s just crazy. It’s easy to argue that structuralism matters less than expected.
Of course biomechanics do matter sometimes. A thousand times, yes. Nothing is black or white. Ask anyone who’s ruptured a tendon. Some problems are obviously firmly rooted in structural troubles.
A good scientific example of this is a pair of 2015 studies, both published by the same researchers. The first study pushes away from structuralism, and the second back towards it. These folks looked at a lot of MRI pictures of spines. Their first paper presented evidence that signs of spinal degeneration are present in very high percentages of healthy people with no problem at all.65 Good to know. And that’s the kind of evidence presented in the last section. I could easily have cited it there.
But the second paper presents evidence that degenerative features visible on MRI are nevertheless “more prevalent in adults 50 years of age or younger with back pain compared with asymptomatic individuals.”66
Also good to know!
What do we do with this delicious cognitive dissonance? 😜 The take-home message is actually just a nice, reasonable compromise between two well-known viewpoints: degenerative changes matter less than many patients and professionals still assume, and are not an adequate foundation for many popular treatments, but they do still matter. Duh.
A perfect example of a structural problem: cluneal entrapment
Or is it? This example is delightfully ambiguous, which makes it perfect. Nothing is entirely structural, and that’s the problem with over-emphasizing it. But some things are quite structural. Like cluneal nerve impingement, a cause of back pain that may be non-rare and probably usually evades diagnosis.
The cluneal nerves pass from the low back and sacrum into the buttocks, just under the skin, and they can get tangled up with ligaments and connective tissue on their way, potentially causing very low back pain. In 2016, Aota reported on “a case of severe low back pain, which was completely treated by release of the middle cluneal nerve.”67 Exploratory surgery identified nerves “entrapped in adhesions.” They cut them free … and that was the ticket. The patient was decisively cured. Which is pretty cool.
That’s about as structural a problem as we can imagine. Tissue in trouble! As physical as tangled sailboat rigging.
And yet it is still possible that her problem was not the nerve “snag” per se but a biological vulnerability to feeling it. The physical predicament of the nerve may have been like kindling for a fire — a fire that was then lit by something else (and which then burned for years).
What else? Biological x-factors, non-structural problems. Biochemistry. Nutrition. Cellular business. Maybe she was vulnerable to that cluneal nerve impingement because of a vitamin D or magnesium deficiency. Or a medication side effect. The biological consequences of sleep deprivation, or sleep apnea (blood gases get weird with that condition). Or the chronic stress of social isolation. Or “inflammaging.” Or any one of about ten thousand other possibilities. The list of could-be’s is almost literally endless.
In this scenario, the nerve entrapment is like kindling for a fire: just inert fuel by itself. That doesn’t mean it’s not a problem — you don’t really want fuel for chronic pain lying around your body just waiting for you to get vulnerable enough for it to burst into flame — but you also don’t blame fuel for a fire. Well, not just the fuel anyway.
This is speculation, of course. It would be difficult indeed to prove causation for even a single example, let alone the whole class of potential vulnerabilities. But I think it’s one plausible explanation for one of the most difficult puzzles in pain science: why obvious physical problems have such inconsistent consequences. (The other big potential explanation, of course, is the psychosocial dimension of pain.)
But even if we could know that it was the vulnerability, not entrapment — and that would certainly be fascinating — diagnosing the vulnerability and solving it could well be a lot trickier than just setting the nerve free. No kindling, no fire! Mostly this problem seems as straightforwardly mechanical as your legs falling asleep because a 40-pound terrier won’t get off your lap.
Another interesting example: the tough lumbar joints of ladies
It is an anatomical fact that women have larger, stronger posterior lumbar joints,68 which is almost certainly a biomechanical feature that has evolved to cope with the combined stresses of pregnancy: the large, awkwardly off-centre weight, and leaning backwards to keep from falling over. This strongly suggests that women with weaker spines, over the aeons, often failed to carry their babies to term because the strain was debilitating. What are the odds that this evolutionary adaptation makes women immune to the back strain caused by pregnancy? Well … nil! Even today, even with tougher spines, pregnant women suffer increased rates of low back pain.
What we take from this is that the importance of spinal curvature is moderated by evolution. We can clearly see that deviations from normal spinal curvature are a factor in back pain, or women would never have evolved an adaptation to cope with it. On the other hand, the same adaptation pretty clearly shows that both men and women are probably adapted enough that spinal curvature alone cannot be a “deal breaker” — if it were, we would have evolved to cope with it.
Another way of putting it: evolution doesn’t care if you have back pain, just as long as you can breed … but it always makes sure that you can do at least that much. It is easy for nature to saddle us with biomechanical features that are uncomfortable and imperfect, but at the same time we are mostly well-protected from biomechanical features that are routinely crippling.
Thus biomechanical factors are usually much less important than is generally supposed.
Structuralists aren’t all wrong or always wrong, of course. Some biomechanical bogeymen truly are scary, and there are times for a structural diagnoses and structural solutions. Some problems are clearly more “mechanical” in nature than others. The menisci in the knee — weird little mobile wedges of cartilage — are a great example of a tricky evolutionary compromise: they do great things for us, but also fail quite a bit.
And yet even for that seemingly mechanical problem, the clinical importance of menscial fraying and tearing is cast into doubt by studies showing that repair is surprisingly ineffective. There is a broad scientific consensus that meniscectomy is useless and risky for most patients.69 It produces results no better than a fake surgery,70 or exercise therapy.71 Severe cases probably benefit more, but no one’s actually tested it yet, and we might be surprised by the results when they do.
Mechanical problems with conceptually simple mechanical solutions exist, but they are rare. While structure does matter sometimes, the evidence overall guides us away from getting our knickers in a collective knot over most of the popular structuralist ideas about pain and injury.
My argument is that biomechanics should be de-emphasized, not ignored, but structuralists are so invested in their perspective that they often react with fierce defensiveness to this article (and all similar arguments elsewhere). They attack the argument by misrepresenting it, and almost always in the same way: they say I’m claiming that biomechanics don’t matter at all, or that I’m throwing the baby out with the bathwater, or both. It’s a blatant straw-man argument — attacking an opinion I don’t actually have — and it gets really tiresome.
And I’m not the only one who’s gotten tired of it! Dr. Jason Silvernail, a particularly expert and articulate physical therapist, has also gotten “really sick to death of this particular canned response.” In 2013 he spontaneously wrote this epic rebuttal, which has been quoted ad infinitum by many like-minded colleagues ever since — it now gets invoked almost every time that annoying straw-man shows its face! Here’s Dr. Silvernail’s exasperated rant in full, reproduced here with his blessing:
Every time pain science gets discussed there are always people who push back and it’s nearly always, acknowledged or not, the straw man of “biomechanics doesn’t matter.” No one has said that biomechanics doesn’t matter. Mechanical origin pain by its nature is biomechanical and the concepts of neurodynamics are also. The problem is that people have been trained to think things like pelvic tilt and core weakness and short muscles are significant biomechanical problems that must be creating a large nociceptive drive that therefore pain science discussions ignore nociceptive pain.
But we need to put biomechanics “in its place” not “out of our mind” when thinking about pain. We need to start to question closely our clinical reasoning processes and realize that not every impairment to movement or function is equally contributing to a pain experience, and many may be irrelevant. We discover which ones are relevant and worth correcting through a systematic assessment and reasoning process — two of the most common and most supported by randomized trials are the McKenzie MDT system and the Maitland manual therapy system.
What we don’t do is assume every kind of positional, movement, muscle length or strength, nerve mobility, or joint accessory movement impairment is contributing nociceptive drive. And that they all need to be addressed and that acknowledging the published research evidence that many of these impairments are normal findings unrelated to the pain experience is somehow ‘ignoring biomechanics’.
It’s a testament to how indoctrinated people are into the biomedical model that their concept of pain begins and ends with their ability to find things to blame and fix in the patients body. I for one won’t apologize for trying to move people in the fitness and rehabilitation world away from such a simplistic, practitioner-centered, outdated view to a more complex, patient-centered, and modern view of the pain experience. If people want to say that means ignoring biomechanics we will just have to keep pointing out this strawman argument when we see it — but I am really sick to death of this particular canned response.
~ Jason Silvernail, DPT, DSc, FAAOMPT, That Grinds My Gears: “You Say Biomechanics Doesn't Matter”
This is a very short section devoted to a small news item, but I think it’s such a significant one that it deserves the focus. First of all, a reminder that “manual therapy” refers methods of trying to treat pain and facilitate recovery from injury with bare hands, especially massage and chiropractic, but also physiotherapy to a great extent. There are literally hundreds of specific examples of manual therapies, and most of them, by nature, assume the existence of tissue glitches that they are intended to “correct.” In other words, most of them are inherently structuralist in character to some degree, and many are completely dominated by it.
So the former journal of Manual Therapy was all about that stuff. But then, in 2017, the journal changed its name to Musculoskeletal Science & Practice. Their under-stated explanation:
The new title will better reflect current practice, education and research in the field of musculoskeletal physiotherapy worldwide and ensure that the journal continues to be a leading publication in the field.
In other words, “manual therapy” was just too narrow, too much about fixing people with techniques and magic hands, and neglected other perspectives and approaches. The change signalled a general retreat from the belief that flesh and structure need to be changed … or even can be. It is writing on the wall that says that manual therapy needs to get beyond being “manual,” because there’s a lot more to this field than structure.
There is a flavour of structuralism for every degree of gullibility, I’m afraid.
For instance, “upper cervical” (NUCCA) chiropractors believe that many if not most health problems not only originate solely from dysfunction of the top-most spinal joint, but that they have the skill to reliably correct all of these problems just by manipulating that joint. This is a classic “extraordinary claim,” hard for many people to swallow, but there is still clearly a market for the service: many patients are charmed by such an elegant-seeming explanation for everything that’s ever gone wrong with them.
Savvier patients are still likely to fall hook, line, and sinker for exactly the same kind of thinking when they encounter a tamer form of it in a massage therapist’s office. A short leg diagnosis certainly sounds like a plausible explanation for back pain to a lot of people. Only the most cynical patients will doubt it. Many patients have complained to me about this diagnosis, but only usually because they simply failed to get any benefit from buying expensive therapy for it, not because they were aware of any problem with the idea itself.
Many hardened skeptics will happily swallow a dubious structural diagnosis when it comes from a doctor reviewing an MRI report — indeed, they will probably swallow it because it comes from a doctor reviewing an MRI report. High-tech medicine is persuasive! Unfortunately, the source doesn’t make it any more true. Countless studies have now shown how misleading MRI can be, how often it reveals harmless structural features and abnormalities that get blown way out of proportion by naive doctors who are just as keen on an easy explanation as the patient is.
Structuralism is immune to credentials, education, and even the great divide between alternative and mainstream medicine. Almost everyone has got the disease of structuralism.
It’s important to understand that there is not really any particular reason for us to believe that we will easily find good advice about aches, pains, and injuries. Unfortunately, most patients seeking care for a knee problem or a shoulder problem don’t realize at first that it may be surprisingly difficult to get good help. If their problem proves to be a stubborn one, it can take several months or even years before to get more cynical and savvy. Along the way, they invariably encounter a lot of structuralism, which they slowly but surely become more and more suspicious of — and yet they will lack the expertise to effectively challenge it.
In the following section I will try to address the question of how common structuralism really is. (Spoiler alert: super common!) In this section, I’ll look at specific healthcare professionals and their relationship to structuralism.
I once worked with a back pain client who had seen at least two dozen structuralists over a period of five years. Literally every health care professional he had seen was a dyed-in-the-wool structuralist, and his mind was quite polluted with their theories: he could hardly open his mouth without saying something about his alleged biomechanical problems. Predictably, there was no agreement between the various diagnoses — everyone had diagnosed a different biomechanical bogeyman. What a mess! So I was thrilled to hear that he had just started seeing a new doctor who was — like me — telling him to stop worrying about his biomechanics.
But it took this patient five years of searching to find just two non-structuralists! We were the first he’d ever encountered.
Family doctors have a proven poor track record in these matters — musculoskeletal medicine, that is.72 They really know quite little, and so they fall into the mental convenience of structuralism easily, just because they’ve never really thought about it one way or the other.
Chiropractors are structuralists pretty much by definition: the profession exists to “adjust” alleged biomechanical problems with the spine and other joints.
Physical therapists (physiotherapists in Canada) are notorious for their preoccupation with the mechanics of the body. I believe that they have fallen into this trap because they do not have clearly defining methodology. Massage therapists massage, chiropractors crack, surgeons cut … but what do physiotherapists do? They are generalists, cherry-picking from a wide variety of therapies, such as strengthening exercises or ultrasound treatments. This is both an obvious strength and a weakness. I have often had the impression that physiotherapists quite literally focus on structuralism because it gives them something to do — something to diagnose, something to therapize, a nice clear theme for their clinical choices.
Massage therapists are not well-trained in most places, and even where training standards are higher, massage therapists barely scratch the surface of pain and rehabilitation science — and so they tend to fall into structuralism because they lack the education they need to deconstruct it, and embracing it is the easiest way for them to feel more competent. For instance, “diagnosing” and “treating” postural dysfunction is an easy way to sound like you’re providing “medical massage.” The unfortunate reality is that most massage therapists simply do not have the academic chops to even try to explain complex musculoskeletal problems.
The most relevant medical specialists: sports medicine doctors, physical medicine and rehabilitation (PM&R), physiatrists, and orthopedic surgeons are the most likely source of competent medical help for aches, pains, and injuries. They are the best-trained and the most likely to be keeping up with the science. But there are caveats! Their practices are often dominated by major traumatic injuries — knees that are “blown” in football games, that sort of thing. Orthopaedic surgeons in particular are (appropriately) preoccupied with these severe cases and building their surgical expertise, and so their knowledge is quite naturally slanted towards structuralism. They all provide invaluable services to people who are concretely and/or severely injured, but they may be just as out of their depth as your family doc with any of the “minor” problems that often plague people. They may dismiss many such problems as trivial, and/or they may humbly recognize that they simply don’t know what to do with them. Chronic overuse injuries that just won’t go away, back pain that comes and goes mysteriously for years, severe neck cricks … these are common problems, yet they are also considered “problem cases” by most of these specialists. I often see patients with these problems who have been to see two or three specialists, all of whom were basically stumped: they tossed out a few structuralist explanations — “Well, it’s probably got something to do with your core strength. Let’s get you to the gym … ” — and then they seemed to lose interest.
Who does that leave? What kind of professional is likely to look for explanations more complex and less satisfying than the easy but often incorrect answers of structuralism?
The sad, ugly truth: no kind of professional. There simply is no such critter. You simply have to find an individual professional who cares, someone who is a determined, humble, and open-minded troubleshooter, someone isn’t obsessed with structuralism. It’s a tall order!
A common complaint about this article is that I make a straw man argument: a case against an imaginary kind of professional. Hardly anyone is actually a structuralist, the argument goes, and no good professional really exaggerates the importance of biomechanical factors. (Ironically and absurdly, the same accusers often then angrily defend their own pet structuralist therapy from my criticisms.)
The straw man complaint is exemplified by this comment on the topic from Leon Chaitow (not a direct reply to me, but to others in my camp):73
… no remotely intelligent practitioner or therapist actually believes that all pain and dysfunction is caused by structural features alone, this is hardly a balanced approach. … Ignoring biomechanics/posture/structure would therefore be as ludicrous as suggesting that back pain (or other) was solely due to biomechanical factors.
Indeed it would. But, unfortunately, I’ve seen a lot more lip service to the idea of a “balanced approach” than a genuinely balanced approach. Professor Gordon Waddell is a low back pain expert and one of the pioneers of alternatives to structuralism, and was writing about “treating patients rather than spines”74 way back in the 80s:
It is all very well to say that we use science and mechanical treatment within a holistic framework, but it is too easy for that framework to dissolve in the starry mists of idealism. We all agree in principle that we should treat people and not spines, but then in daily practice we get on with the business of mechanics.
Gordon Waddell. The Back Pain Revolution. 1998.
This topic is controversial and has sparked many heated debates in every possible context, from scientific journals to Facebook. The majority of the social media kerfuffles I’ve seen — and I’ve seen hundreds — have been fights about the validity of one structuralist sacred cow or another. Numbers are impossible (without some research that won’t ever be done), but my experience strongly suggests that structuralism is not only common but still the dominant way of thinking about musculoskeletal pain.
I’m hardly alone in that opinion. Here’s a supportive reader report from the UK, describing the dominance of structuralism in that country:
Lederman’s “The Myth of Core Stability” has been available on our physiotherapy website for years, and yet I still hear the same old core stability nonsense churned out on a daily basis. My biggest gripe is why the universities (over here in England anyway) keep on teaching the same old syllabus, and don’t evolve their courses in line with current evidence. There is still a huge emphasis on passive treatments and different ways in which we can ‘fix’ our patients it’s scary. And until we start to produce physios with a different schooling and a different mindset, unfortunately I can’t see there being much of a paradigm shift in the near or distant future.
Pete Gray, Physiotherapist, Nottingham
Maybe there are significant differences between professions in different parts of the world.75 But here in my own backyard — and damn near everywhere else, apparently, as suggested by a decade of constant substantive correspondence with patients and professionals around the world — structural and biomechanical factors generally reign supreme, routinely emphasized by manual therapists to the near exclusion of most other therapeutic considerations. I have seen a never-ending parade of clients with biomechanical past diagnoses, but (almost) never seen a patient who said, “Well, the last guy talked all about psychosocial factors, sensitization, and the possibility of vulnerability due to vitamin D deficiency!” Which should be the rule, not the (vanishingly rare) exception.
Instead, while many non-biomechanical factors in chronic pain may be paid some lip service, they are rarely/barely used to actually guide clinical choices. Merely mentioning them does not constitute useful application of the evidence to a patient’s difficult situation. Few clinicians seem to be aware of that evidence, fewer still seem to know what to do with it — and so they continue to strongly favour biomechanical factors, because it’s familiar and easy.
I am even guilty of over-emphasing structural factors myself, despite years of denouncing structuralism. I know exactly how tempting a perspective it is. I was originally taught to treat people with my hands, and I still tend to think like a sculptor of flesh — a meat repairman — regardless of whether that actually makes any sense. I strain to prevent that way of thinking from dominating, but I have often failed. I have often made the error of fixating on that which is more concrete and easier to hold in my mind, easier to explain to patients, easier to chase with my hands.
You can’t grab and “adjust” the subtle factors that drive most “mechanical” pain, like stress and insomnia, addiction, inflammaging and metabolic syndrome, or a subtle pathology of connective tissue. And so most health professionals have a strong and understandable mental predisposition to structuralism.
Yes, well of course, and that’s all fine and good, but don’t throw the baby out with the bathwater.
~ most of the world’s manual therapists, before getting back to biomechanical business as usual
Here’s a fine rant from Norwegian physical therapist Sigurd Mikkelsen about an all-too typical clinical experience with structuralism coming from a sports doc. (And please note: the harsh language is not a transcript of his actual clinical communication, but a frustrated description of how he felt about it.)
Things that piss me off … first consultation today — a young active girl with an ACL injury. She got told by the doctor that she’d never play football again after looking two seconds on her MRI. Which instantly scared the shit out of her and all her dreams about sports and becoming a police woman were brutally shattered.
She cried (out of relief) when I told her this Doc should go F%&K the H#LL off and told her how Kjetil Jansrud won Olympic Gold in Super-G one year after his ACL-injury. Then went off with a 15 min continuous heroic rant about how fu&king fantastic and adaptable our bodies and minds are and threw around stories about great comebacks and insane human achievements. She felt better when she left the office.
FFS!!! Mind your words!!! They can change lives forever!
I hear stories like this on a daily basis, and I have for my entire career: patients are constantly told depressing, scary, bogus things about their injuries, based on shallow examination and the pernicious belief that we are like fragile machines — as opposed to freakishly resilient biological marvels. My inbox is full of it, like it’s coming from a firehose. And that’s why I get so exasperated when I get “don’t throw the baby out with the bathwater” reactions every time I try to swing the clinical reasoning pendulum away from structuralism and “fragilistic thinking”. The pendulum has never even come close to descending to a balance point between a biomechanical perspective on musculoskeletal medicine versus a neuro/bio one … let alone actually swinging too far in the other direction.
One particularly insiduous sub-species of structuralism involves elaborate “dot connecting” theories. Most structuralism takes the form of straightforward causes like “a narrowed spinal canal causes back pain” (it doesn’t, not on its own, not inevitably; again see Haig et al). Structuralism tends to be presented this way even when the biomechanics are obviously not that simple.
But professionals who really embrace structuralism like to “connect the dots,” the better to impress their patients. For instance, a podiatrist might tell you that your fallen arches (dot!) cause greater strain in your knees (dot!), which in turn forces you to use your hips differently (dot!), which leads to hip weakness (dot!), then muscle imbalance in the core (dot!), which finally results in back pain (dot!). The best dot connectors can be quite convincing, painting elaborate pictures of interconnectedness and inviting you to share a wise chuckle about how “everything really is connected.”
Indeed, the foot bone really is connected to the leg bone, and so on. That complex biomechanical relationships exist is not in question. 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 narrowed spinal canal does not predict stenotic back pain. Many people with ITB syndrome do not have a tight IT band. 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 relatively simple biomechanical factor, what are the odds that they are going to agree on the causal relationships between three or more of them?
Therapists use dot-connecting structuralism to impress their patients … and themselves. The dot-connecting thing is inextricably connected with ego tripping. This is explored more thoroughly in the article The Not-So-Humble Healer.
Why are patients so tolerant of structuralism? Why do they so consistently believe something that is so easy to disprove? Something that doesn’t even produce results?
Because it is human nature to believe whatever feels good. And structuralism feels good, for both patients and professionals, mainly because we love the simplicity of it. Simplicity is just satisfying, and more compatible with optimism: simple problems are fixable problems. Although the messiness biology should have cured us of this by now, we still tend to think of our bodies as unusually complicated machines, and structuralism plugs right into that.
Of course many structuralist theories aren’t necessarily simple in their details, and may even involve elaborate dot-connecting, but they all basically boil down to something we can tell people the next day at the water cooler: “My pelvis is out of whack.” So easy! And so much the better if we can impress upon our audience that our clever therapist was able to trace the causal pathway through nine intermediate misalignments — but it’s still boils down to just “out of whack.”
The body is assuredly not just a complicated machine that gets out of whack, but an absurdly complex evolutionary experiment in organic chemistry. Mechanical imagery is an almost completely useless way to achieve a good understanding of musculoskeletal health. By analogy, doctors have learned that there is a great deal more to an obstructed artery than “clogging” — instead, it involves a bewildering array of biochemistry mediated by countless factors, more complex than anyone dreamed possible a hundred years ago.
Similarly, physical therapists must get past mechanics. Joints may be like hinges in a superficial way, but they are not hinges, work nothing like hinges, fail nothing like hinges, and heal nothing like hinges. Yet structuralism is a rather transparent and pathetic attempt to explain pain as a mechanical breakdown, described in terms that are indeed quite simplistic compared to the breathtakingly complex reality that is your tissues.
The seductiveness of believing what feels good is extremely potent, not to be underestimated. Given the choice to believe in something that feels good but is wrong, and something that is true but disconcerting, the human animal will go with “feels good” almost every time. This tends to result in the proliferation of every imaginable kind of product, service, and scam that appeals to our desires. We actually do constantly spend time and energy on “solutions” that don’t work — whether it’s a kitchen widget, a stock tip, or physical therapy. Knowing what we know about human nature, it would be amazing if we weren’t collectively prone to excessive optimism about health care theories.
Carl Sagan’s book, the classic The Demon-haunted World, thoroughly and brilliantly illuminates this aspect of our species, giving countless examples of how belief and gullibility is driven by our craving to live in our comfort zones.
When we believe that something “makes sense,” we can spend years stubbornly looking for evidence that we’re correct (confirmation bias). Our comeuppances can be delayed for years, or even entire lives, by the tendency to misinterpret evidence in our favour. But let me tell you where that path leads for an intellectually honest professional, because I have been doing this job long enough now to have read a great deal of science (much more than the average clinician will ever have time for). There’s simply nothing there to support structuralism as a broadly useful model for how pain and injury and rehab work. After decades of trying, researchers still can’t actually find the phenomena that they obviously think “must” exist for structural explanations of pain to work. And, meanwhile, clinicians keep repeating the mechanical explanations.
Posture, structure and biomechanics have had their day in the research sun; they have had their chance to make a difference. We’ve wrung almost as much explanatory power and clinical relevance out of that paradigm as we’re ever going to. The returns on our research investment started diminishing long ago, and now we’re scraping the bottom of the barrel. Meanwhile, overuse injuries and chronic pain march on, just as nasty as ever before, and probably much worse. It is time to move on to new ways of explaining and treating pain.
I have received many cranky complaints over the years about this article, most of them calling me out for being too negative and failing to provide alternatives to structuralism.
It isn’t my responsibility to tell professionals what should replace a failed conceptual model. It’s a big enough job just making the case that the emperor has no clothes — it’s not feasible for me to also pick out a new wardrobe for him to wear tomorrow, and even if I could it wouldn’t make him any less naked today. And what if nothing in particular can replace structuralism? The naked truth is important on its own, no matter how depressing. Maybe it’s okay for the emperor to be a nudist.
And yet I think there are some good alternatives to structuralism.
I spent at least the last few years of my own career as a busy massage therapist, helping people every day but only occasionally motivated by structuralism. It didn’t feel difficult. If anything, it felt much easier — and more honest — than constantly fine-tuning elaborate biomechanical rationalizations for what I was doing, which never felt done, because it couldn’t be.
This is my basic prescription for a non-structuralist approach to helping people recover from injuries and chronic pain: avoid causing pain and generating nocebos, create novel and pleasant sensations, treat chronic pain more like other chronic illnesses, and be an expert guide and an encouraging coach.
You’d think that avoiding causing pain would be obvious, but it really does need to be said. Most physical and manipulative therapy, for at least a quarter century now, has had the same basic goal to alter the state of peripheral tissues, because of the guiding principle that there must be something wrong with those tissues in need of fixing. Much of that work is done in vain, because there is rarely anything wrong that can actually be fixed. And yet repair is often attempted at the cost of a bunch of caustic sensory input, because it turns out that trying to fix flesh often involves uncomfortable, forceful tactics, like a wide variety of intense massage, most dramatically scraping with hard tools, high velocity joint “adjustments”, stabbing sore spots with needles (“dry needling”), and so on and on. Luckily for patients, their brains usually interpret those sensations as “good for me, no pain no gain”; they hope and assume they are safe, and so surprisingly little harm is done, and sometimes even some good, albeit largely accidental good.
But there also many exceptions: some people are downright traumatized by the tough love of intense, meat-manglin’ therapy.76 It’s not common, but it should be completely unheard of.
The main problem with the focus on tissue fixing is usually just a missed opportunity to do other, better things. Here is my prescription in some more detail:
- At all costs, avoid doing harm with harsh sensory input in the name of therapy. Also avoid doing harm with nocebo — give people neurologically sound reasons to be hopeful, instead of biomechanical bogeymen to be worried about!
- Start trying to interact with nervous systems instead of fixing flesh. Creatively generate pleasant, interesting, and/or useful sensory experiences.
- Treat chronic pain more like other chronic illnesses:77 work on a strong relationship with patients, coach and teach, encourage exercise, troubleshoot critical lifestyle factors like insomnia, smoking, anxiety etc.
- For all problems — new unexplained pain, chronic pain, injury rehab — embrace your role as a knowledgeable guide through the maze of theories and possibilities. Learn as much as possible about pain neurology and physiology, and then pass it on. Empower patients to save themselves, because you actually can’t … but you can teach. You can train patients how to minimize and eliminate aggravating factors and other impediments to recovery (which is all “healing” ever really is). But, above all, explain pain, because pain is weird and needs explaining badly!
None of this properly evidence-based. I cannot point to studies that show that therapists who work this way produce better results for their patients. There is a buttload of indirect and “circumstantial” evidence that it’s well worth trying, but definitely no clear evidence of efficacy, which is a shame but totally unsurprising at this point in history. Remember, I’m just giving my ideas about an alternative to an extremely dominant treatment paradigm.
On the bright side, this methodlogy also hasn’t actually been undermined by evidence the way structuralism has, and it definitely has something structuralism has never had: plausibility, based on a much better modern understanding of how chronic pain actually work. Plus it has a strong do-no-harm theme, which is a great feature.
In search of “practical” solutions
Many professionals chafe at the lack of “something practical that can be implemented,” as one reader put it. That desire is understandable, but it’s also nearly impossible to satisfy.
The biggest problem in manual therapy is over-reliance on the “practical” — modalities, techniques, methods, “tools for the toolbox.” Most of these exist because they are marketable, appealing solutions to problems that are exaggerated if not downright imaginary. Wiser, more nuanced, and complex ideas about how to help people with chronic pain — the only kind that matter — are always overshadowed by more “practical” approaches, which are literally designed to be more promising. The market has been supplied with so many of these “practical” options for so long that anything more realistic is inevitably going to seem vexingly inaccessible by comparison.
Greg Lehman’s Fundamentals of Treatment
Another example of non-structuralist treatment model is Greg Lehman’s Fundamentals of Treatment, AKA Axioms of Function (described in detail in Treatment Fundamentals). All of these are great points, but #4 is particularly relevant here.
- Rule out red flags
- Rule out serious tissue pathology
- The body is strong and adaptable
- Pain is more about sensitivity than about injury
- Treatment is about finding the appropriate stressor
- The patient is an active participant in their own care
- Decorations (“Useful Though Not Fundamental Axioms”)
- Gauge your treatments by assessing sensitivity
- Manual therapy is an adjunct to fundamentals
- Your assessment reinforces their belief in strength
- Comprehensive capacity trumps assessment-driven correctives
- Postural and movement assessments reveal habits but not flaws
I think this model does a great job of taming excessive structuralism without throwing it out entirely, which is classic Lehman: he teaches a course called “Reconciling Biomechanics With Pain Science.”
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About Paul Ingraham
I am a science writer in Vancouver, Canada. I was a Registered Massage Therapist for a decade and the assistant editor of ScienceBasedMedicine.org for several years. I’ve had many injuries as a runner and ultimate player, and I’ve been a chronic pain patient myself since 2015. Full bio. See you on Facebook or Twitter.
I received a note from a reader — allegedly a colleague and kindred spirit. He thanked me for my writing, and then asked:
Would you like to know what actually causes trigger points? I have been at this for twenty years and have the answers that we all search for.
Uh oh. Clearly, this is someone who fancies himself a “healer” with special knowledge — almost certainly a structuralist theory. His delusions of grandeur are betrayed not only by his belief that he has “the answers that we all search for,” but by his teasing lack of detail. If he really has special knowledge, why would he ask me if I want to know? Why wouldn’t I? Why be guarded or vague? Just share! Can you imagine a scientist writing to another scientist and saying, “Would you like to know how things really work?”
I decided to bite, just to see what he would say, and his reply was vain and vague, with hand-waving references to an “amazing” therapeutic protocol that can work marvels with pain patients, and all of it depending on something — he doesn’t say what — in the feet. This is classic wind up for a doozy of a structural theory to explain all pain. For structuralists, “it all” always hinges on one critical biomechanical factor.
I pointed out that his lack of humility, lack of detail, and lack of scientific evidence was all fairly off-putting. And this was his reply, pitch perfect for a delusional “healer.” I have reproduced it here word for word, because it is just such a gloriously irritating example of this kind of thinking, which is absolutely rampant in alternative health care:
I appreciate what you are saying, I have been humble for 2 decades now, in fact this has been my ministry for 20 years. As I have said I don’t have all the answers and I don’t have a panacea for anything, neither have I cured anything, I’ve worked with many alternative types of medicine and have used these methods to end my own bout with cancer. What makes my method work is a complimentary adjustment top to bottom. What makes the adjustment stay is the cuboid [a small foot bone] being held in place. If you have the skills needed to reduce or eliminate the scoliosis then you can appreciate that just to get proper treatments in some areas, you have to fight. I am entirely guilty of being an old warrior, who finally has won. I don’t need to argue any more, I demonstrate. I have no desire to change the way things are, only to save as many as I can. Technical explanations are good for conversing with doctors, but my mission is to communicate with the average joe who has been through the “mill” and has lost hope, these are my flock. To check out my “ extraordinary claims” You will find confirmation in Dr. Warren Hammers book entitled; Soft tissue examination and treatment by manual methods pg 425.
Is a stable cuboid bone “the answer” to all pain? Don’t bet on it!
There are so many things about his thought process that are disturbing that I hardly know where to begin, but here are the highlights:
- Well, first of all, “I have been humble for 2 decades now” is not an expression of humility. No one gets bragging rights for being humble!
- Unsurprisingly, he attributes his miraculous healing abilities to a single biomechanical factor … and a small one at that, the cuboid bone, a sugar-cube sized lump of bone in the foot which he can therapeutically “hold in place,” implying both that it could be significantly and disastrously loose before his treatment (it can’t), and that he has the magic hands to somehow ensure that it remains firmly in place after his treatment (he can’t). Man, this really is structuralism as its most outrageous!
- In the attempt to seem humble, this guy claims that he doesn’t have all the answers and that he hasn’t cured anything … but then in the same paragraph he goes ahead and claims that his method depends on a single biomechanical factor, directly implies he can cure, that he’s “an old warrior who has finally won”, that he wants to “save” people, and that he can reduce or eliminate scoliosis — a condition that I have never seen successfully treated in my career, despite the efforts of many who claimed they could.
- Like every intellectually lazy quack, he dismisses the importance of “technical explanations.” They are good “for conversing with doctors” … something I think we can safely bet he doesn’t actually ever do.
- He cites a single reference as “confirmation” for a wildly optimistic, extravagant claim of therapeutic efficacy. Wow, that must be some reference! That brings oversimplification of a complex subject to new lows!
And a final dig I can’t resist …
- He is allegedly a complementary medicine professional … but he can’t spell it. How sad. Also, he can’t punctuate. As my father always said, “Bad writing doesn’t necessarily mean you’re stupid, but it sure makes you look stupid.”78
This is why so many doctors so reasonably object to alternative medicine: because it is, so often, so disappointingly ego-driven.
- The Not-So-Humble Healer — Cocky theories about the cause of pain are waaaay too common in massage, chiropractic, and physical therapy
- “The fall of the postural–structural–biomechanical model in manual and physical therapies: Exemplified by lower back pain,” Eyal Lederman, Journal of Bodywork & Movement Therapies, 2011. This article is a bloody brilliant deconstruction of the underlying assumptions of the vast majority of pseudo-quackery in the manual therapies. It’s technical and academic, not for the lay reader, but absolutely required reading for professionals. Be sure to read his other excellent essay, “The Myth of Core Stability”.
This article was many years old before I started logging updates in Apr, 2010. Its date of origin is lost. It probably evolved out of several other article written between about 1998 and 2003.
2019 — Audio version reboot: I just re-did the audio version of this article, including dozens of updates in recent years. I’ve also changed the way I produce audio version so that I can easily updated individual chapters in the future. The audio is available on request to visually impaired readers, and as a perk for all eboxed set customers.
2019 — Update/correction: Meniscal fraying is no longer a good example of a clearly structural problem with a clear structural solution, not that we know that so much mensical repair surgery is ineffective. Corrected and clarified [Updated section: Disclaimer! Structure is not completely irrelevant.]
2019 — New sub-topic: Added some thoughts and a new citation about muscle “imbalances” (over and under-developed muscles on one side or the other). [Updated section: Scientific evidence that structuralism is a failed paradigm.]
2018 — Example added: New sub-section, “A perfect example of a structural problem,” based on a fascinating case study reported by Aota. [Updated section: Disclaimer! Structure is not completely irrelevant.]
2018 — Science update: Added a key citation Lewis et al and elaborated a little on my recommendations. [Updated section: “Prescriptions” for pros — how to move on from structuralism.]
2018 — Science update: Beefed up the description of the alternative to structuralism, and added a new citation and a few old ones. [Updated section: Introduction.]
Archived updates — All updates, including 13 older updates, are listed on another page. ❐
- Do they really? The prevalence of the proclivity will be discussed a bit further along. (And by “manual therapists,” I mostly mean the three professions most likely use their hands for therapy: physical therapists, chiropractors, and massage therapists.)
- From a group discussion amongst therapists online:
In my view all upper quadrant injury except for the hands comes down to the inability of the body to control scapular depression. It is also my view that all injuries of the lumbar spine and lower extremities are due to the inability to perform a kinesiological squat.
One can’t help but wonder what all hand problems are attributed to! The absolutism here is glaringly arrogant and nonsensical, the thinking of low calibre — for instance, there is no such thing as a “kinesiological squat” — but this is alarmingly typical of structuralist theories.
- It’s a “forefoot varus,” meaning that the front of the foot is twisted away from the midline. It’s minor and subtle, but unambiguous. As soon as I could walk, I did so with my right foot turned out. The first time my parents took me cross-country skiing, when I was just a tiny lad about three years old, I had trouble keeping my right ski in the track! It just kept popping out. The problem remained undiagnosed for three more decades, and was finally identified by a superb pedorthist, Paul Rauhala, of OKAPED in Canada’s Okanagan Valley. “Basically, the whole big-toe side of your foot is lifted up,” he explained. “The easiest way for you to get it down for push-off is to rotate your whole leg out.” It’s interesting (1) how many therapists I’d seen over the years who were obsessed with “fixing” my posture and biomechanics but totally missed my one obvious actual deformity, (2) how little it really affects me (chronic mild pain), and (3) how impossible it is to do anything about it anyway. I tell the story of my funky foot in more detail in my plantar fasciitis tutorial.
- The channelopathies. Dysautonomia from subtle/intermittent myelopathy. The hypermobility spectrum disorders and Ehlers–Danlos syndrome, often almost clinically invisible, and yet strongly linked to aches and pains. Vitamin D deficiency. Analgesic rebound. “Inflammaging,” possibly excessive due to metabolic syndrome (or many other factors). And so on.
- Christensen JO, Johansen S, Knardahl S. Psychological predictors of change in the number of musculoskeletal pain sites among Norwegian employees: a prospective study. BMC Musculoskelet Disord. 2017 Apr;18(1):140. PubMed #28376786 ❐ PainSci #53601 ❐
More aches and pains are predicted by “several psychological & physiological factors,” namely “emotional exhaustion, mental distress, sleep disturbance, tiredness and headache intensity.” Increases in those factors were associated with more pain sites, and decreases with fewer pain sites.
- Behrend C, Prasarn M, Coyne E, et al. Smoking Cessation Related to Improved Patient-Reported Pain Scores Following Spinal Care. J Bone Joint Surg Am. 2012 Dec 5;94(23):2161–6. PubMed #23095839 ❐
This study added to the pile of evidence that smoking is “associated with low back pain, intervertebral disc disease” along with many other medical complications. Their conclusion, after studying the records of more than 5000 patients with “axial or radicular pain from a spinal disorder,” was that there is a “need for smoking cessation programs for patients with a painful spinal disorder.” Very likely both neck and back, of course.
- Pain itself often modifies the way the central nervous system works, so that a patient actually becomes more sensitive and gets more pain with less provocation. This is called “central sensitization.” (And there’s peripheral sensitization too.) Sensitized patients are not only more sensitive to things that should hurt, but also to ordinary touch and pressure as well. Their pain also “echoes,” fading more slowly than in other people. See Sensitization in Chronic Pain: Pain itself can change how pain works, resulting in more pain with less provocation.
- Ingraham. Pain is Weird: Pain science reveals a volatile, misleading sensation that is often more than just a symptom, and sometimes worse than whatever started it. ❐ PainScience.com. 11274 words. Modern pain science shows that pain is a volatile, complex sensation that is thoroughly tuned by the brain and often overprotectively exaggerated, so much so that sensitization often becomes more serious and chronic than the original problem. All of this has complicated “all in your head” implications: if the brain controls all pain, does that mean that we can think pain away? Probably not, but we do have some “neurological leverage” of great value — we can influence pain, if we understand it.
- This idea has been touted by Dr. Janet Travell of trigger point fame, and repeated by Amber Davies in a popular book about trigger points, and by at least one book by a podiatrist.
- The Latin root “derm” usually refers to the skin, and many sources define it only in that way, while others show that it also means layer. The dual meaning can also be inferred from its usage in the names of the three embryonic layers — endoderm, ectoderm and mesoderm — which are invariably defined as inner, outer, middle layers and not “skin”. I suspect that skin has come to be the dominant definition because it is the most prominent example of the more general concept of a layer, in the same way that “Levis” are synoymous with “jeans” or “John Hancock” means any signature (this is synecdoche). Skin is the layer, the alpha derm!
- Just in case anyone needs to know exactly how ridiculous that is: the coriolis effect is a macroscopic effect, and does not have a visible effect on small systems like water going down a drain. “The Coriolis force is so small that it plays no more role in determining the direction of rotation of a draining sink anymore than it does the direction of a spinning CD” (from the “Bad Coriolis” page). The idea that coriolis force would be relevant to musculoskeletal health is about as air-headed as you can get.
- From the official FMS website. Note that the website has lots of marketing and promotional language, and generally makes FMS sound amazing. However, in principle FMS is not intended to be a “diagnostic” tool and it’s only in practice that it tends to get used that way.
- Placebo is belief-powered relief from symptoms, while nocebo is the opposite: belief-powered symptoms, or “the placebo effect’s malevolent Mr. Hyde” (Gareth Cook). “Nocebo” is Latin for “I shall harm” (which I think would make a great supervillain slogan). Give someone a sugar pill and then convince them you actually just fed them a deadly poison, and you will probably witness a robust nocebo effect. A common funny-if-it’s-not-you nocebo in general medicine is the terror of “beets in the toilet”: people eat beets, and then think there’s blood in the toilet, and call 911. Nocebo is a real thing, and not to be messed with. It is one of the chief hazards of excessive X-raying and MRI scans, for instance: showing people hard evidence of problems that often aren’t actually a problem. A screening test that reveals alleged problems might do it too. The course of back pain is remarkably sensitive to stress and anxiety.
- Flynn TW, Cleland JA, Schaible P. Craniosacral therapy and professional responsibility. J Orthop Sports Phys Ther. 2006 Nov;36(11):834–6. PubMed #17154136 ❐ For instance, with regards to craniosacral therapy, Flynn wrote: “It is also imperative that physical therapy professionals who perform cranial techniques do not communicate to patients disproved concepts of moving cranial sutures or balancing cranial rhythms. This language is disingenuous and may lead to creating disability in our patients by providing the perception that there is some sort of structural deformity in their body and implying that they are ill.”
- Weisberg DS, Keil FC, Goodstein J, Rawson E, Gray JR. The seductive allure of neuroscience explanations. Journal of Cognitive Neuroscience. 2008 Mar;20(3):470–7. PubMed #18004955 ❐ PainSci #53859 ❐
This study found that ordinary people were more satisfied with bogus neuroscience talk than experts were. In other words, less educated folks are somewhat more likely to swallow fancy-sounding bullshit.
I believe bogus biomechanics talk is even more persuasive to non-experts than neuroscience babble. Although neuroscience is used to explain pain more often than it used to be, explaining pain in terms of biomechanics still rules in most therapy offices in the land. Patients easily understand levers and misalignment. They don’t question it; they don’t even want to. Explaining pain with neuroscience is a way tougher sell. If you don’t do it just right it comes off as a complicated version of “all in your head,” which it’s definitely not. If patient are able to accept bogus neuroscience explanations for pain, I gaurantee they are much more willing to accept bogus structural explanations.
- I do not think that this is an unreasonable accusation. Patients with great anxiety, pain and frustration are especially vulnerable to persuasion, or “therapy by charisma.” This is why I really make an effort in my work to be reassuring without offering miracles, to be knowledgeable without claiming to “know” what the problem is. All too often, patients in pain will cling to whatever ideas you throw at them … so you have to be careful what you throw at them! Structuralists rarely seem to show such restraint, and consequently patients emerge from therapy with structuralists feeling much too sure of their diagnosis. There is no zealot like a convert! In this context, clinicians are more like clergy than health care professionals.
- Many lines of evidence suggest that pain is not tightly linked to tissue damage, and I’ll be reviewing many other examples below. But Finan et al was an instant classic, a study of 113 people that looked at exactly this issue. They found a clear pattern of people with knees that look bad on a scan, but feel fine, and vice versa. As Tony Ingram summarized it, people “who had a little arthritis and high pain & people with severe arthritis but low pain.”
- Strange, wonderful, and problematic anatomical variations occur in humans all the time. Over the years, I’ve collected several interesting examples relevant to musculoskeletal medicine. For more information, see You Might Just Be Weird: The clinical significance of normal — and not so normal — anatomical variations.
- Dye SF. The pathophysiology of patellofemoral pain: a tissue homeostasis perspective. Clinical Orthopaedics & Related Research. 2005 Jul;436:100–110. PubMed #15995427 ❐ PainSci #56695 ❐ From the article: “The fundamental issue at the core of the patellofemoral pain problem, in this author’s view, has been the limited conceptualization of the genesis of anterior knee pain to that of a pure structural and biomechanical perspective. Such an intellectually constrained view does not include the complex pathophysiologic factors that may be of etiologic significance in living, symptomatic joints.”
- Lederman E. The fall of the postural–structural–biomechanical model in manual and physical therapies: Exemplified by lower back pain. J Bodyw Mov Ther. 2011 Apr;15(2):131–8. PubMed #21419349 ❐ PainSci #55668 ❐
This article is a bloody brilliant deconstruction of the underlying assumptions of the vast majority of pseudo-quackery in the manual therapies. It’s technical and academic, not for the lay reader, but absolutely required reading for professionals. Be sure to read his other excellent essay, “The Myth of Core Stability”.
- Chaitow L. Is a postural-structural-biomechanical model, within manual therapies, viable? A JBMT debate. J Bodyw Mov Ther. 2011 Apr;15(2):130–52. PubMed #21419348 ❐ PainSci #55071 ❐ Most of what is good in the rebuttals is consistent with what I’ve already conceded: namely that, yes, duh, structure is sometimes clinically relevant. But the rest of it fails to address the concerns that both Dr. Lederman and I have raised.
- AmericasPodiatrist.com [Internet]. Nirenberg M. Biomechanics of Sport Shoes: The Disturbing Truth About Running Shoes, Inserts and Foot Orthotics; 2012 Oct 2 [cited 14 Nov 27].
- Zusman M. The Modernisation of Manipulative Therapy. International Journal of Clinical Medicine. 2011 Nov;2(5):644–9. PainSci #54598 ❐
- More: “This is further inexplicable in the light of evidence that not only the underlying “philosophy” but also several of the fundamental requirements of the clinical process itself which has the structural-mechanical model as its basis, have been shown to be flawed or at least irrelevant. The apparent inability of the profession to fully abandon outmoded “concepts” (and embrace the acknowledged science-based “best practice” biopsychosocial model) may have potentially undesirable consequences for both patients and therapists engaged in the management of (chronic) musculoskeletal pain and disability.”
- Deyo RA, Weinstein DO. Low Back Pain. N Engl J Med. 2001 Feb;344(5):363–70. PubMed #11172169 ❐
- Bogduk N. What’s in a name? The labelling of back pain. Medical Journal of Australia. 2000;173(8):400–401. PainSci #56046 ❐
- And he may well have gone too far down that road. For an overview of his work, see Critical Analysis Review of Dr. John Sarno’s Books & Ideas.
- Ingraham. Why Does Pain Hurt? How an evolutionary wrong turn led to a biological glitch that condemned the animal kingdom — you included — to much louder, longer pain. ❐ PainScience.com. 5043 words. Research has shown that immune cells (neutrophils) unnecessarily “swarm” sterile injury sites, causing damage and pain with no known or likely benefit as a tradeoff. It’s just a clear error: they appear to have mistaken mitochondria for a foreign organism, a legacy of ancient evolutionary history, and a biological glitch with profound implications about why some painful problems are so severe and stubborn.
- Mizumura K, Taguchi T. Delayed onset muscle soreness: Involvement of neurotrophic factors. J Physiol Sci. 2016 Jan;66(1):43–52. PubMed #26467448 ❐
- Sapolsky RM. Why Zebras Don’t Get Ulcers. 3rd ed ed. New York: Times Books; 2004.
- Dr. Moseley has many books and articles I could link to, but I think the best and most entertaining introduction to Lorimer is his 2012 TED talk, Why Things Hurt 14:33.
- Moseley L. Teaching people about pain — why do we keep beating around the bush? Pain Management. 2012;2(1):2–3. PubMed #24654610 ❐ PainSci #54762 ❐
- Littlewood C, Malliaras P, Bateman M, et al. The central nervous system--an additional consideration in 'rotator cuff tendinopathy' and a potential basis for understanding response to loaded therapeutic exercise. Man Ther. 2013 Dec;18(6):468–72. PubMed #23932100 ❐ For instance, in a paper about rotator cuff tendinopathy, Littlewood et al. write that explanations for pain based on “peripherally driven nociceptive mechanisms secondary to structural abnormality, or failed healing, appear inadequate.”
- You could certainly debate whether muscular “trigger points” are one of the viable alternatives to structuralism. It largely depends on what you think is the cause of trigger points. Simons remained quite open-minded until his death in early 2010. Although he had proposed and defended the “metabolic crisis” model, he often emphasized the limits of what the evidence can tell us so far. Regardless of their true nature, trigger points are certainly a clinically interesting and important phenomenon — and decidely not an idea based on biomechanics and structure.
- As Carl Sagan famously pointed out, “science delivers the goods” — like landing on the moon, or curing deadly diseases with antibiotics — which is how we know that science is a useful process. Treatments and therapies based on structuralism have conspicuously failed to produce obvious such benefits for patients.
- Grundy PF, Roberts CJ. Does unequal leg length cause back pain? A case-control study. Lancet. 1984 Aug 4;2(8397):256–8. PubMed #6146810 ❐
This classic, elegant experiment found no connection between leg length and back pain. Like most of the really good science experiments, it has that MythBusters attitude: “why don’t we just check that assumption?” Researchers measured leg lengths, looking for differences in “lower limb length and other disproportion at or around the sacroiliac joints” and found no association with low back pain. “Chronic back pain is thus unlikely to be part of the short-leg syndrome.” Other studies since have backed this up, but this simple old paper remains a favourite.
- Cooperstein R, Lucente M. Comparison of supine and prone methods of leg length inequality assessment. J Chiropr Med. 2017 Jun;16(2):103–110. PubMed #28559750 ❐ PainSci #52779 ❐
Assessments of leg length are common, both with the patient lying down or standing. Either could be reliable, but in this test they did not agree with each other. Two chiropractors with more than 30 years experience each assessed the same few dozen patients, and agreement between their results when they felt confident in them was “perfectly nil.“ Despite the widespread and confident use of each method, this test clearly suggests that at least one of them is unreliable, but it’s also entirely possible that both of them are.
- Wallace IJ, Worthington S, Felson DT, et al. Knee osteoarthritis has doubled in prevalence since the mid-20th century. Proc Natl Acad Sci U S A. 2017 Aug;114(35):9332–9336. PubMed #28808025 ❐
Knee osteoarthritis is thought of a “wear-and-tear” problem aggravated by weight and age. In this experiment, this assumption was tested for the first time using “long-term historical or evolutionary data.” They looked at the skeletal remains of older people with a well-documented body mass index from the last two centuries (industrial and post-industrial); they also looked at prehistoric knees. The prevalence of osteoarthritis has roughly doubled in recent history (20th century) — and that number didn’t change when weight and age were factored out. The implications are clear: loading and longer lifespans are almost certainly not the cause of knee arthritis!
So what, then? Although this data doesn’t show it, the unconfirmed but obvious candidate is the surge in the modern lifestyle diseases: metabolic syndrome, diabetes, heart disease (see Kluzek et al or Jiang to start down that rabbit hole). Which is good news: those problems are more preventable than aging.
- Christensen ST, Hartvigsen J. Spinal curves and health: a systematic critical review of the epidemiological literature dealing with associations between sagittal spinal curves and health. J Manipulative Physiol Ther. 2008;31(9):690–714. PubMed #19028253 ❐
This review of more than 50 studies found no association between measurements of spinal curves and pain. The authors’ conclusion was decisive: the evidence “does not support an association between sagittal spinal curves and health including spinal pain.” One can cherry pick the data for a few studies that show some minor correlation, but it averages out to nothing to write home about.
- Schneiders AG, Davidsson A, Hörman E, Sullivan SJ. Functional movement screen normative values in a young, active population. Int J Sports Phys Ther. 2011 Jun;6(2):75–82. PubMed #21713227 ❐ PainSci #55282 ❐
According to the authors of this study, the Functional Movement Screen™ (FMS) is “based on the assumption that identifiable biomechanical deficits in fundamental movement patterns have the potential to limit performance and render the athlete susceptible to injury.” However, this small, high-quality experiment could not even detect a difference in test results in people who had actually been injured recently: the results “demonstrated no significant differences on the composite score between individuals who had an injury during the 6 last months and for those who had not.”
On the bright side, this study did confirm that the FMS testing is reliable (inter-rater reliability): different professionals get almost exactly the same results. It also produced good baseline test results for average active people, which is an important first step in helping professionals (and future researchers) start to understand the meaning of FMS results — if any.
For more detailed analysis of this paper, see The Functional Movement Screen (FMS).
- Tumminello N, Silvernail J, Cormack B. The Corrective Exercise Trap. Personal Training Quarterly. 2017 Mar;4(1). PainSci #52905 ❐ Summarizing their examination of the premise of corrective exercise and tests like the FMS, the authors conclude: “It is often assumed that identified so-called ‘dysfunctions’ in posture, movement quality, or body function are reliably predictive of potential injury and performance, the preponderance of the scientific evidence casts a great amount of doubt on any claims about the strength and reliability of such relationships.”
- Grob D, Frauenfelder H, Mannion AF. The association between cervical spine curvature and neck pain. Eur Spine J. 2007;16(5):669–678. PubMed #17115202 ❐ PainSci #56033 ❐ Other experiments do show a correlation, but never a strong one. The experts can debate the evidence, but … it’s debatable, rather than being a smoking gun. The point is that there is no clear connection between neck posture and neck pain.
- Wright AA, Wassinger CA, Frank M, Michener LA, Hegedus EJ. Diagnostic accuracy of scapular physical examination tests for shoulder disorders: a systematic review. Br J Sports Med. 2013 Sep;47(14):886–92. PubMed #23080313 ❐
- In a Facebook discussion, a chiropractor enthused about “shoulder dyskinesis” got annoyed with a physical therapist for calling it a “dubious” clinical concept. He asked for evidence and linked to a PubMed search, suggesting that the existence of so many papers about it must mean it’s legit. That was too good a rebuttal opportunity for me to pass up: a slow pitch right across home plate. Evidence that shoulder dyskinesis is dubious? In those search results, it took me all of 10 seconds to find Wright et al on the first page. That paper alone is hardly a fatal blow for the validity of SD, but it is amusing that the challenge could be answered with such discouraging science that was so easy to find! Furthermore, while other papers are less obviously negative, none are clearly positive either. The literature is only clear about one thing: the clinical significance of SD is ambiguous and equivocal at best.
- Hickey D, Solvig V, Cavalheri V, Harrold M, Mckenna L. Scapular dyskinesis increases the risk of future shoulder pain by 43% in asymptomatic athletes: a systematic review and meta-analysis. Br J Sports Med. 2017 Jul. PubMed #28735288 ❐ Although this paper’s title seems to defy skepticism about the importance of scapular dyskinesia, it is extremely misleading, and the actual conclusion is the opposite of what’s implied. This is a great example of lying with statistics: it’s only a 43% greater relative risk, relative to a small total count of injuries. The difference in absolute risk is very minor, and the authors write in the body of the paper that “screening for scapular dyskinesia is not a useful approach to predict shoulder pain.” So even in a paper with a headline blatantly biased in favour of the importance of structuralism, we end up with the paper’s own authors conceding precisely the opposite.
- Moseley JB, O’Malley K, Petersen NJ, et al. A controlled trial of arthroscopic surgery for osteoarthritis of the knee. N Engl J Med. 2002 Jul 11;347(2):81–8. PubMed #12110735 ❐ PainSci #56845 ❐
- Salata MJ, Gibbs AE, Sekiya JK. A Systematic Review of Clinical Outcomes in Patients Undergoing Meniscectomy. Am J Sports Med. 2010 Jun;28(9):1907–16. PubMed #20587698 ❐ With regards to mechanical knee alignment, Salata et al reviewed seven papers relevant to knee alignment: three showed a connection between poor alignment and degeneration, four found none. So the evidence is “mixed,” but the connection cannot be strong if four radiographic studies came up empty.
- See Boden, Jensen, Weishaupt, Stadnik, and Borenstein.
- Haig AJ, Tong HC, Yamakawa KS, et al. Spinal stenosis, back pain, or no symptoms at all? A masked study comparing radiologic and electrodiagnostic diagnoses to the clinical impression. Archives of Physical Medicine & Rehabilitation. 2006 Jul;87(7):897–903. PubMed #16813774 ❐
In this study, about 150 people were assessed for back pain in different ways, including MRI, but “radiologic and clinical impression had no relation.” In other words, there was no useful similarity between evaluation of the patient with MRI, and evaluation by examination and taking a history. “The impression obtained from an MRI scan does not determine whether lumbar stenosis is a cause of pain.” Since MRI does in fact identify narrowing of the spinal canal, and this is the whole basis of diagnosing spinal stenosis with MRI, these results also strongly imply that a narrowed spinal canal does not (alone) cause back pain.
- Kim C, Nevitt MC, Niu J, et al. Association of hip pain with radiographic evidence of hip osteoarthritis: diagnostic test study. BMJ. 2015;351:h5983. PubMed #26631296 ❐ PainSci #53332 ❐
This analysis of thousands of patients confirmed a jarring disconnect between signs of arthritis on hip x-rays and hip pain: “Hip pain was not present in many hips with radiographic osteoarthritis, and many hips with pain did not show radiographic hip osteoarthritis.” What they mean by “many” is “practically all”: roughly 80% of patients with signs of arthritis had no pain, and at least 85% of patients with hip pain had no sign of arthritis! These numbers held up even at the extremes — most older patients with a high suspicion of hip arthritis did not in fact have arthritis that could be diagnosed with an x-ray.
- “Type I (elongated) was the most frequent type on both sides (42/59); and the most frequent patterns of calcification were partially calcified on the left side (18/59) and completely calcified on the right side (16/59). Only two patients were symptomatic.” Ilgüy 2005
- Buchbinder R, Osborne RH, Ebeling PR, et al. A Randomized Trial of Vertebroplasty for Painful Osteoporotic Vertebral Fractures. N Engl J Med. 2009 Aug 6;361(6):557–568. PainSci #55333 ❐
This is one of a pair of 2009 papers (see also Kallmes et al) presenting strong evidence that there is “no beneficial effect” to stabilizing fractured spines with injections of bone cement (vertebroplasty), a common and yet apparently dubious procedure. That evidence is backed up by major reviews published since (Buchbinder 2015, Stevenson 2014), but some contrary evidence has also been published (Shi 2012, Klazen), and it is possible vertebroplasty works better for some kinds of patients.
Nevertheless, it’s a major comeuppance for a seemingly straightforward surgical fix that should have been tested more carefully long ago. And if stabilizing the spine with cement doesn’t resolve symptoms, it strongly suggests that instability wasn’t the problem to begin with. The rationale for vertebroplasty has always been cave-man simple: Ooog. Verteba [sic] busted. Hurt. Thag make bone stronger. Inject glue. Ugh. Supposedly these fractures are painful because the spine is unstable — hardly an unreasonable assumption — and therefore stabilizing them will help. Except it didn’t!
- Bittencourt NF, Meeuwisse WH, Mendonça LD, et al. Complex systems approach for sports injuries: moving from risk factor identification to injury pattern recognition-narrative review and new concept. Br J Sports Med. 2016 Jul. PubMed #27445362 ❐
- Devan MR, Pescatello LS, Faghri P, Anderson J. A Prospective Study of Overuse Knee Injuries Among Female Athletes With Muscle Imbalances and Structural Abnormalities. J Athl Train. 2004;39:263–267. PubMed #15496997 ❐ PainSci #56601 ❐
- Lun V, Meeuwisse WH, Stergiou P, Stefanyshyn D. Relation between running injury and static lower limb alignment in recreational runners. Br J Sports Med. 2004 Oct;38(5):576–80. PubMed #15388542 ❐ PainSci #53470 ❐
- Hespanhol Junior LC, De Carvalho AC, Costa LO, Lopes AD. Lower limb alignment characteristics are not associated with running injuries in runners: Prospective cohort study. Eur J Sport Sci. 2016 Jun:1–8. PubMed #27312709 ❐
- Liddle SD, David Baxter G, Gracey JH. Physiotherapists' use of advice and exercise for the management of chronic low back pain: a national survey. Man Ther. 2009 Apr;14(2):189–96. PubMed #18375174 ❐
This survey of 600 Irish physiotherapists showed that advice and exercise were the treatments most frequently used for chronic low back pain. Advice was most commonly delivered as part of an exercise programme, and strengthening (including core stability) was the most frequently prescribed exercise type.
- Morris SL, Lay B, Allison GT. Corset hypothesis rebutted - Transversus abdominis does not co-contract in unison prior to rapid arm movements. Clin Biomech (Bristol, Avon). 2011 Oct. PubMed #22000066 ❐
“These findings indicate that training bilateral pre-activation of the transversus abdominis prior to rapid movement is not justified and may potentially be problematic for the production of normal movement patterns.” This significantly undermines a classic theory (see Hodges et al) used to justify an “advanced” approach to core strength training.
- Childs JD, Teyhen DS, Casey PR, et al. Effects of Traditional Sit-up Training Versus Core Stabilization Exercises on Short-Term Musculoskeletal Injuries in US Army Soldiers: A Cluster Randomized Trial. Phys Ther. 2010 Jul. PubMed #20651013 ❐
- Unsgaard-Tøndel M, Fladmark AM, Salvesen O, Vasseljen O. Motor Control Exercises, Sling Exercises, and General Exercises for Patients With Chronic Low Back Pain: A Randomized Controlled Trial With 1-Year Follow-up. Phys Ther. 2010 Jul. PubMed #20671099 ❐ This study compared a good, typical dose of two different kinds of core training exercises to general exercise and found no difference at all.
- Cherkin DC, Sherman KJ, Kahn J, et al. A comparison of the effects of 2 types of massage and usual care on chronic low back pain: a randomized, controlled trial. Ann Intern Med. 2011 Jul;155(1):1–9. PubMed #21727288 ❐ PainSci #55286 ❐ See also a detailed analysis of this study.
- Hides J, Fan T, Stanton W, et al. Psoas and quadratus lumborum muscle asymmetry among elite Australian Football League players. Br J Sports Med. 2010 Jun;44(8):563–7. PubMed #18801772 ❐ Researchers used MRI to measure the size of kicking muscles in 54 Australian Football League players — very serious athletes, these guys, playing a very rough sport. First the authors proved that they do have major muscle imbalances — bigger kicking muscles on one side! — and then proved that they were “not related to the number of injuries” in those athletes. I repeat: Not. Related.
- Given the roughness of the sport, perhaps it is to be expected that injuries would be more related to collisions and less related to muscle asymmetries. Perhaps so. However, these athletes are likely to have been training heavily off the field as well. And structuralists would argue that muscle asymmetry creates a vulnerability to injury, which should show up in any sport if they are correct. It didn’t here.
- Young SW, Dakic J, Stroia K, et al. High Incidence of Infraspinatus Muscle Atrophy in Elite Professional Female Tennis Players. Am J Sports Med. 2015 Aug;43(8):1989–93. PubMed #26078449 ❐
This odd little study reports a pattern of infraspinatus atrophy in the shoulder of elite female tennis players. (The infraspinatus is one of the four small “rotator cuff” muscles that control fine movement of the shoulder joint.) Such atrophy is common in “overhead athletes,” but it doesn’t appear to be a problem: in these tennis players, atrophy correlated with better performance, not worse, and had no association with any shoulder problems. This appears to be a “muscle imbalance” that’s actually a good thing: something about elite peformance in tennis actually requires or causes it.
- Brinjikji W, Luetmer PH, Comstock B, et al. Systematic Literature Review of Imaging Features of Spinal Degeneration in Asymptomatic Populations. AJNR Am J Neuroradiol. 2015 Apr;36(4):811–6. PubMed #25430861 ❐ PainSci #53872 ❐
- Brinjikji W, Diehn FE, Jarvik JG, et al. MRI Findings of Disc Degeneration are More Prevalent in Adults with Low Back Pain than in Asymptomatic Controls: A Systematic Review and Meta-Analysis. AJNR Am J Neuroradiol. 2015 Dec;36(12):2394–9. PubMed #26359154 ❐
- Aota Y. Entrapment of middle cluneal nerves as an unknown cause of low back pain. World J Orthop. 2016 Mar;7(3):167–70. PubMed #27004164 ❐ PainSci #53097 ❐
- Whitcome KK, Shapiro LJ, Lieberman DE. Fetal load and the evolution of lumbar lordosis in bipedal hominins. Nature. 2007;450(7172):1075–1078.
- Thorlund JB, Juhl CB, Roos EM, Lohmander LS. Arthroscopic surgery for degenerative knee: systematic review and meta-analysis of benefits and harms. BMJ. 2015;350:h2747. PubMed #26080045 ❐ PainSci #53297 ❐ A review of nine studies as of 2015 presenting strong collective evidence that meniscectomy is a futile surgery for most patients.
- Sihvonen R, Paavola M, Malmivaara A, et al. Arthroscopic partial meniscectomy versus sham surgery for a degenerative meniscal tear. N Engl J Med. 2013 Dec;369(26):2515–24. PubMed #24369076 ❐ “In this trial involving patients without knee osteoarthritis but with symptoms of a degenerative medial meniscus tear, the outcomes after arthroscopic partial meniscectomy were no better than those after a sham surgical procedure.”
- Kise NJ, Risberg MA, Stensrud S, et al. Exercise therapy versus arthroscopic partial meniscectomy for degenerative meniscal tear in middle aged patients: randomised controlled trial with two year follow-up. BMJ. 2016;354:i3740. PubMed #27440192 ❐ PainSci #53299 ❐
This large trial compared exercise to surgical cleanup of the menisci and found “no clinically relevant difference was found between the two groups … at two years.” They didn’t include patients locked knees, trauma, and most had no osteoarthritis.
- Doctors lack the skills and knowledge needed to care for most common aches, pains, and injury problems, especially the chronic cases, and even the best are poor substitutes for physical therapists. This has been proven in a number of studies, like Stockard et al, who found that 82% of medical graduates “failed to demonstrate basic competency in musculoskeletal medicine.” It’s just not their thing, and people with joint or meaty body pain should take their family doctor’s advice with a grain of salt. See The Medical Blind Spot for Aches, Pains & Injuries: Most physicians are unqualified to care for many common pain and injury problems, especially the more stubborn and tricky ones.
- In a Facebook discussion, Aug 2010.
- Waddell G. 1987 Volvo Award in Clinical Sciences: a new clinical model for the treatment of low-back pain. Spine. 1987;12:632–44. PubMed #2961080 ❐
An excellent summary of medical knowledge of low back pain … for the late 1980s, anyway. Waddell is a good writer, and a respected authority in the field (and he continued publishing well into the 2000s).This is one of the earliest anti-structuralism papers I’m aware of.
- In particular, I suspect that North America is more “structuralist” than Europe. I have noted that the Aussies seem particularly interested in evidence-based care and generally show a high awareness of recent research. Good on ya, Australia!
- For instance, via the mechanism of central sensitization. See Sensitization in Chronic Pain.
- Lewis J, O’Sullivan P. Is it time to reframe how we care for people with non-traumatic musculoskeletal pain? Br J Sports Med. 2018 Jun. PubMed #29941618 ❐
This editorial is an excellent, brief explanation proposal for treating chronic pain like other chronic illnesses: “strong clinical alliance, education, exercise and lifestyle (sleep hygiene, smoking cessation, stress management, etc) in order to build the individual’s self-efficacy to take control and ultimately be responsible for their health.” But “clinical evidence is lacking.”
- I reserve the right to critisize other peoples writing even though I also mak mistaks the sometimes. Writing with many glaring errors exposes a lack of mental rigour and maturity. A minimum of literacy is required to be taken srsly. See Typos & Nitpicking Hypocrisy.