Skepticism about trigger points (TrPs) and myofascial pain syndrome surged with the publication of an important opinion paper in late 2014. But this started more than 20 years before that…
So, it’s a scholarly pissing match! A polarizing poopstorm. To an almost alarming degree, it seems that everyone is now on one team or the other. I have biases that pull me in both directions.9 Lucky for me, I don’t actually have to choose a team to root for: I’m just reporting on the key features of the public debate, for readers who are wondering what all the fuss is about.
Because of this argument/debate, many professional now believe and assert in various ways that trigger points are not “real.” They often do this without making a critical distinction between the clinical phenomenon (which no one disputes) and the explanation for it.
Everyone agrees that people often suffer from many aching spots in their soft tissues. There’s even broad agreement about some their clinical characteristics — they are sensitive when poked, for instance.
The argument is about almost everything else — what they are, how they work, whether they can be felt, and so on. It’s mainly an inside baseball argument about the explanation for the problem commonly known as “trigger points.”
If you are skeptical about the nature of trigger points, please beware of suggesting to patients that they aren’t real.
The “expanded integrated hypothesis” is on the trial: the “official” explanation for those sore spots. In a nutshell, this hypothesis says that a trigger point is a kind of tiny cramp in muscle tissue. It has been exhaustively described in many texts, books, papers, articles, and this website. It was presented by Dommerholt, Gerwin, and Shah in 2004. It’s detailed and technical!10 (Go ahead, read that footnote, I double dare ya.) When abridged and oversimplified, it still closely resembles the integrated hypothesis (“a possible explanation”) put forward by Travell and Simons in 1981. It basically says this:
Quintner et al. believe that what seems to be muscle pain is not caused by any problem with muscle tissue itself. They think the integrated hypothesis is “flawed both in reasoning and in science” and “an invention without a scientific basis.” They think it’s therapy babble. Maybe they are right.
Even today, trigger points remain an idea on the fringes of health care, despite their alleged importance. There may be a “conventional wisdom” about them, but it’s certainly not mainstream, and the scientific argument about it is even more obscure.Treating trigger points as if the conventional wisdom is correct is a big business. It may be dwarfed by the scale of most health care, but it is still a large slice of the musculoskeletal medicine pie.
Although medical history is peppered with competing theories and debate about the nature of MPS/TrPs, direct criticism of the modern conventional wisdom is rare. I cannot emphasize strongly enough that almost everyone not only uncritically accepts the conventional wisdom, but treats patients as though it were an established fact and a firm foundation for expensive therapy. Treating trigger points as if the conventional wisdom is correct is a big business. It may be dwarfed by the scale of most health care, but it is still a large slice of the musculoskeletal medicine pie.
In other words, TrPs do need criticizing. Right or wrong, agree or disagree, what Quintner et al. have done is valuable and important. We need to hear from anyone who believes the Emperor has no clothes.
Quintner et al. make three main arguments against MPS/TrPs:
They also present “testable hypotheses are identified that point the way to neuroscientific explanations for the observed clinical phenomena.” These ideas can’t show that the IH is wrong any more than belief in one god can disprove another, but their plausibility is relevant.
Despite the appearance of a strong disagreement, I see a lot of common ground. On the one hand, Quintner et al. concedes that people experience pain and sensitivity that seems to be in muscle tissue. The pain is real, and the need for an explanation and effective treatment is real:
This is not to deny the existence of the clinical phenomena themselves, for which scientifically sound and logically plausible explanations based on known neurophysiological phenomena can be advanced.
Meanwhile, Team Dommerholt concedes that we still don’t really know what’s going on:
A distinct mechanistic understanding of this disorder does not yet exist.
…there has never been a credible anatomic pathology associated with myofascial TrPs.
There are several more concessional statements like this in their rebuttal (which Quintner et al. gleefully quote back at them).11 Dommerholt et al. don’t seem to mind the uncertainty. They know they’re working with “just a theory.”
We did not present new data as dogma, but followed the scientific process of re-evaluating the Integrated TrP Hypothesis as new data became available.
So Quintner et al. do not deny that there is a painful phenomenon, and propose an alternative explanation that is strikingly similar: just one sort of irritated tissue (nerve) instead of another (muscle). And just as unvalidated. Just a theory. And Dommerholt et al. obviously concede that the science is half-baked and we don’t know for sure how this kind of pain works — we just have circumstantial evidence.
With all this common ground, what’s the argument about?!
Quintner et al. argue that the idea of trigger points is completely bankrupt and no longer worth pursuing — if it ever made any sense at all.
The construct of MPS caused by TrPs remains conjecture. All working hypotheses derived from this conjecture have been refuted and therefore the theory can be discarded.
MTrP theory has been well and truly refuted
It is time to shine the light of critical inquiry elsewhere in pursuit of explanations for these clinical phenomena.
This is a dramatic conclusion. I think it’s fair to call it absolutist: they are not just saying the conventional wisdom has problems, they are declaring it dead. But to convinct the integrated hypothesis of fraud and send it to the electric chair, its “guilt” must be established “beyond a reasonable doubt.”
To remain viable as an unproven hypothesis, the defense only has to establish that the idea still has some merit and further investigation is worthwhile. Which is not a high bar to clear, particularly when everyone agrees there’s a painful problem that needs explaining. I think Dommerholt et al. step over that low bar fairly easily. They present many evidence-informed counter-arguments, which constitute “reasonable doubts,” and conclude:
Quintner et al. have not succeeded in providing sufficient evidence that the current TrP hypotheses should be rejected.
They aren’t saying it should be accepted — just that it’s not all washed up. That’s an easier position to defend.
I heartily endorse the spirit of what Quintner et al. are trying to do. Their criticisms are valuable, and I am moved by many of their arguments — I am just not moved off the fence. I think there are reasonable doubts about the “guilt” of trigger points. I cannot in good conscience convict them of fraud.
Quinter et al. represent an isolated expert minority of skeptics on this topic. There are no other scholarly papers like theirs. There is no body of research supporting their own competing hypothesis — indeed, “the three included references do not provide any support for their assumption.”12 There are no books that you can recommend to someone who has trigger point doubts. None of this means that they are wrong, but it’s relevant context.
Compare and contrast this with other ideas that have been declared dead, where there is an avalanche of objections in the scientific literature: vaccines causing autism, homeopathy, chiropractic subluxation theory, acupuncture, and so on. Those are dead horses (or, at the very least, the controversies about them are heavily skewed in favour of the skeptics).
In comparison, the hypothesis of a metabolic crisis in muscle seems merely wounded — declaring its death is premature. It’s a legitimate scientific controversy, and debate and study should continue.
I am a science writer, former massage therapist, and I was the assistant editor at ScienceBasedMedicine.org for several years. I have had my share of injuries and pain challenges as a runner and ultimate player. My wife and I live in downtown Vancouver, Canada. See my full bio and qualifications, or my blog, Writerly. You might run into me on Facebook or Twitter.