It’s easy to look up into the deep, dark sky and see the patterns. Each star is an amazing point of interest in a sea of light and provides infinite questions for us to think about. The stars we see have literally birthed us all; each atom in our body was created in the furnace of a star. And as Lawrence Krauss has said, the atoms in your right hand may be from a different star than the ones in your left hand. With a little imagination, the night sky is an open canvas for us to sketch crude portraits of the ancient gods and mythological heroes from days past. To the people of antiquity, the starry night sky must have been a true wonder. With no real certainty as to what they were looking it, and occasionally seeing figures from their collective imagination, I truly cannot imagine the intellectual perplexity they faced.
But we know a bit more now. We know now that the classical constellations, while they are neat to look at, and provide some utility in organizing the night sky, are essentially arbitrary groups of stars. They are signals we think we see amongst the noise. We know that the movement of celestial bodies has no impact on our life events. From anywhere but our perspective on earth, these constellations simply vanish. Apophenia describes the human tendency to ascribe meaning to meaningless patterns. As Michael Shermer terms it, our “patternicity” may be an evolutionary adaptation that can help us recognize danger.
“The cost of believing that the rustle in the grass is a dangerous predator when it is just the wind is relatively low compared with the opposite. Thus, there would have been a beneficial selection for believing that most patterns are real.” (Shermer, 2008)
Seeing patterns and assuming agency is a trait that helped humans survive and was thus selected for. But with modern life being somewhat less dangerous, apophenia can now lead us astray.
Meaningless Maps
Fascial trains, chains, and meridians are popular biomechanical boogeymen (see Your Back Is Not Out of Alignment by Paul Ingraham) that have been the supposed cause of, and/or contributing factor towards, painful musculoskeletal conditions. Popularized in Anatomy Trains, author Tom Myers maps out the most commonly travelled fascial highways and suggests that these maps can provide new insights into diagnosis and treatment of musculoskeletal problems. Myers suggests that there are functional connections of fascia throughout the body that play a significant and underappreciated role in human movement. And while Myers humbly and appropriately offers a caveat to his claims that “It is too early in the research process to claim an objective reality for these lines,” (Myers, 2) he also makes the claim that his book “leaps ahead of the research” (Myers, 1).
It is challenging to nail down exactly what Myers is claiming here. Do fascial lines actually exist as functional entities? Are these connections simply dissected out strategically? If fascia is throughout the body, why do these particular patterns matter? How do you know they matter? LIke the constellations and other heavenly bodies, are the connections being drawn simply aesthetically pleasing ways of organizing points of interest, with no real deeper meaning? Do the patterns we think we see have any real-life consequences? The burden of proof is on them to (1) show that fascial trains actually exist and (2) to define the precise role they play in treatment. The research on the subject thus far, however, leaves some room for doubt.
- Wilke et.al. (2016) performed a systematic review of the anatomy and dissection literature in order to determine if there is any evidence showing the existence of fascial continuities, as outlined by Myers. The researchers focused on finding connections for the following lines: the superficial back line, the superficial front line, the lateral line, the spiral line, the back functional line, and the front functional line. The researchers found that for the superficial back line, the back functional line, and the front functional line there were some continuities between major structures. For the other lines, there were significant gaps in continuity, casting some doubt on their existence. Is it possible that these researchers may have fallen victim to confirmation bias? They were specifically looking for connections that would prove them right. Couldn’t there be a huge number of hypothetical fascial trains that they could have sought connections for? What would they have found if they weren’t psychologically primed to see the ones already outlined? You can’t unsee a constellation after someone connects the dots for you ahead of time.
For fairness sake, let’s steel-man Myers’ claims and assume that there are fascial connections that can be found during an honest and unbiased dissection. What role do they actually play in clinical practice? Do fascial connections matter? Can fascia even be targeted and treated specifically? There are a few interesting studies that attempt to answer these questions.
- Wilk et.al. (2016) compared local stretching to remote stretching based on fascial patterns for improvements in cervical spine range of motion. The researchers divided up approximately 60 participants into a local stretching group who stretched cervical muscles, a remote stretching group who stretched their hamstrings and calves, and a control group who did nothing. Unsurprisingly, the control group saw no changes. But more interestingly, the researchers found that both local and remote stretching groups had improvements in cervical spine range of motion, and there was no difference between these groups. Certainly an unintuitive result. There might be a few explanations for this. The authors suggest that it may be related to mechanical force transmission of fascia, in line with Myer’s claims that distal fascial work may induce proximal changes. Other proposed explanations include global stretch tolerance improvements via central neural pathways, or neurodynamic improvements. But here is a rather large caveat that the authors did try and explain, but not to my satisfaction. The resulting changes in cervical spine range of motion were not direction specific. If the superficial back line truly exists as Myers suggests, then presumably the increase would be seen in cervical flexion. But the authors only reported total range of motion in each plane, and increases were seen in all planes. The authors also suggest that force transmission can go in multiple directions, and not just along the “anatomy train,” which begs the question: why do we care about this specific train then? A more parsimonious explanation for the results in this study may be that patients received a treatment that they were (presumably) told would help improve neck movement, and unsurprisingly, both groups saw their neck movement improve a bit.
- Studies by Grieve et.al. and Patel et.al. in 2014 and 2016 respectively, assessed the efficacy of a treatment technique proposed by Myers in Anatomy Trains, involving the superficial back line. Myers suggests that a good way to improve a toe touching pattern is to release a portion of the SBL by rolling out the plantar fascia and then retesting the movement. Both sets of authors did exactly that and assessed performance on a sit and reach box, and Patel et.al. also included the active knee extension test as an outcome measure. The 2014 study saw small improvements in the sit and reach, and the 2016 study saw small improvements in only the active knee extension test. Unfortunately for the researchers, neither study included a placebo group, and the control group was completely inactive. So Myers is right that rolling the plantar fascia may improve a toe touch pattern, but neither study took the more interesting path and included a placebo group that performed fascial release outside of the proposed anatomy train. Again, placebos and patient expectation may be in play here. It seems more reasonable to me that a patient may perform better on a test after receiving a treatment, or any treatment, that they were told would help them improve.
- In the often cited Chaudhry et.al. 2008, the authors created a mathematical model for the amount of force needed for mechanical deformation of fascia. Spoiler alert: it’s a lot.
“The dense tissues of plantar fascia and fascia lata require very large forces—far outside the human physiologic range—to produce even 1% compression and 1% shear.”
So whatever is happening during manual therapy techniques designed to target fascia, it likely isn’t that fascia is “releasing.” Our body probably is more resilient, and not like play-doh where if you mash on it long enough, it will smooth out. Additionally, there is no reason to believe that any of our manual treatments target fascia specifically; if it it is truly everywhere, how can you target it and avoid anything else? Now Myers doesn’t propose a specific mechanism by which these treatments works, but words matter. And it certainly seems to be more complex than fascial adhesions along anatomy trains just breaking up. There is more to the story we really don’t know yet.
Getting Off The Anatomy Train
Evidence is evidence however, and I could easily envision a few studies that would show that Myers may be onto something interesting. My mind could be changed with the following study: recreate the study by Wilke 2016, and have a few different groups: local stretching, remote stretching on a track of the appropriate anatomy train, remote stretching on a track of a completely different train, and then an inactive control group. This would control for the treatment effect of a novel stimulus presented as something beneficial, regardless of direction specificity. If both remote stretching groups improve we know that it isn’t the trains that matter, and just the fact that a treatment is being administered that is proposed to help, and probably being delivered by a caring therapist.
Now some of these treatments may work some of the time and for some of the patients. I just think we have some room for doubt that the successes that are seen are due to changes in fascial restrictions along anatomy trains. We don’t assume horoscopes are right because sometimes they accurately describe a few people you know a few times. Statements or concepts that are vague enough can be applied to anything. But Myers suggests that it doesn’t matter how a treatment works and it’s not our responsibility to propose a mechanism of action (Myers, 2). I would like to humbly disagree. It absolutely matters. If we don’t try to answer these questions, we fall victim to cognitive errors and confirmation bias. We need to know what we do to patients and how it occurs. Everything is worth investigating. We risk making the same mistake as the astrologers; we ought not to look at what we see with a passing glance and only pay attention to the cases that confirm our beliefs. We ought to try and put our ideas and concepts to the test; and the harder the test it passes, the more confident we can be in our convictions.
It seems that Myers and followers are playing a game of anatomical astrology; drawing connections that seem to fit particular patterns that we think we see and suggesting these patterns have real life implications. The challenging task is proving that these connections matter in any meaningful way. Myers’ trains seem somewhat implausible on their face, but not outside the realm of possibility and thus worthy of a little bit of digging. The treatments that are suggested however, have faced a few arguably biased and “easy” tests in the aforementioned trials with lukewarm results. We haven’t seen it pass any hard tests just yet. I would love to see some of these concepts survive a few tough randomized controlled trials, because I want to help my patients just as much as Myers or anyone else does. I simply need more evidence to suggest that this isn’t just an example anatomical apophenia. I am open, but doubtful. The problem for me is that it seems the anatomy train doesn’t have an interesting destination, and I will need to see more evidence before I buy my ticket.
References
- Chaudhry, H. et.al. (2008). Three-Dimensional Mathematical Model for Deformation of Human Fasciae in Manual Therapy. Journal Of American Osteopathic Association, Volume 108, Number 8
- Grieve, R. et.al. (2015) The immediate effect of bilateral self myofascial release on the plantar surface of the feet on hamstring and lumbar spine flexibility: A pilot randomised controlled trial. Journal Of Bodywork and Movement Therapy, Volume 19
- Ingraham, P. Your back Is Not Out Of Alignment. https://www.painscience.com/articles/structuralism.php
- Myers, T. (2009) Anatomy Trains: Myofascial Meridians For Manual And Movement Therapists. 2nd edition
- Patel, D. et.al. (2016). The immediate effect of bilateral self myofascial release on the plantar surface of the feet on hamstring and lumbar spine flexibility: a quasi-experimental study. International Journal of Therapeutic Applications, Volume 32
- Shermer, M, (2008). Patternicity, http://www.michaelshermer.com/2008/12/patternicity/
- Wilke J, et.al. (2005) What is evidence-based about myofascial chains? A systematic review, Archives Of Physical Medicine And Rehabilitation.
- Wilke, J. et.al. (2016): Is remote stretching based on myofascial chains as effective as local exercise? A randomised-controlled trial, Journal of Sports Sciences
Factual Physical Therapy 