Research · Trigger points
Trigger point research: the evidence and the debate
"Trigger point" is one of the most used terms in hands-on work, and one of the most argued about in research. These are the studies that shaped both sides, summarised as their authors wrote them.
In short
- An international expert panel agreed that a trigger point is identified by a taut band, a very tender spot and referred sensation (Fernández-de-las-Peñas & Dommerholt, 2018).
- Small studies of nine people each found differences in ultrasound images and local chemistry at these spots (Sikdar et al., 2009; Shah et al., 2008).
- Examiners don't reliably find the same points by hand (Lucas et al., 2009), and critics argue the theory behind them has no scientific basis (Quintner et al., 2015).
- Even the critics don't deny the tender spots people feel. The dispute is about what those spots are.
- What a trigger point is said to be
- Looking inside the muscle
- The case against
- What it means for hands-on work
What a trigger point is said to be
Myofascial trigger points then and now: a historical and scientific perspective
Shah JP, Thaker N, Heimur J, et al. · PM&R 2015;7(7):746–761
What they did. Researchers from a group that has studied trigger points with imaging and biochemistry traced the idea from early descriptions through Travell and Simons to recent work.
What they found. They describe a trigger point as a hard, discrete nodule in a taut band of muscle, painful on its own (active) or only when pressed (latent). They acknowledge that terms, theories and diagnostic criteria remain inconsistent or controversial.
Limits. Written by researchers who support the trigger point model; read it alongside the critical papers below.
International consensus on diagnostic criteria and clinical considerations of myofascial trigger points: a Delphi study
Fernández-de-las-Peñas C, Dommerholt J · Pain Medicine 2018;19(1):142–150
What they did. Three rounds of questions to an international expert panel aimed to agree how a trigger point should be identified.
What they found. The panel agreed on three essential criteria: a taut band, a hypersensitive spot and referred pain. Active and latent points differ in whether they reproduce the person's own symptoms.
Limits. Agreement among experts, not a test of how accurate those criteria are.
Studies that looked inside the muscle
Both studies come from the same research group and are small. They are often cited as evidence that trigger points are physically distinct.
Novel applications of ultrasound technology to visualize and characterize myofascial trigger points and surrounding soft tissue
Sikdar S, Shah JP, Gebreab T, et al. · Archives of Physical Medicine and Rehabilitation 2009;90(11):1829–1838
What they did. Upper trapezius sites judged by hand to contain active, latent or no trigger points were examined with ultrasound by a team blinded to the physical findings.
What they found. Trigger point sites showed up as small, focal, stiffer regions on ultrasound. Sites with active points had a distinctive blood flow pattern nearby.
Limits. Nine participants; the authors call the findings preliminary.
Biochemicals associated with pain and inflammation are elevated in sites near to and remote from active myofascial trigger points
Shah JP, Danoff JV, Desai MJ, et al. · Archives of Physical Medicine and Rehabilitation 2008;89(1):16–23
What they did. A microdialysis needle sampled the chemistry of the upper trapezius in people with active, latent or no trigger points, and of a calf muscle for comparison.
What they found. People with active trigger points had higher levels of inflammatory mediators, neuropeptides and related substances in the trapezius, and also in the uninvolved calf muscle.
Limits. Nine people. It shows a difference between groups, not what causes it.
The case against
Reliability of physical examination for diagnosis of myofascial trigger points: a systematic review of the literature
Lucas N, Macaskill P, Irwig L, et al. · The Clinical Journal of Pain 2009;25(1):80–89
What they did. The review gathered studies testing whether different examiners find the same trigger points by hand.
What they found. Agreement varied widely. It was better for tenderness and pain reproduction than for the taut band or twitch response. The authors conclude that physical examination cannot yet be recommended as a reliable test for trigger points.
Limits. None of the included studies met all quality criteria, and newer criteria (2018) were not yet tested.
A critical evaluation of the trigger point phenomenon
Quintner JL, Bove GM, Cohen ML · Rheumatology 2015;54(3):392–399
What they did. The authors examined the evidence that trigger points exist as distinct pathological entities, and for the cycles said to maintain them.
What they found. They conclude that the trigger point theory of myofascial pain lacks a scientific basis and has been refuted. They do not deny the tender spots people feel, and suggest explanations based on known nerve physiology instead.
Limits. A critical review by authors with a stated position; read it with the supporting papers above.
What this means for hands-on work
Practitioners work on tight, tender spots whatever they call them. Trigger PRO is a manual massage tool that helps hold steady pressure where you choose. None of the studies on this page tested it, it takes no side in this debate, and it makes no claim about what a trigger point is.
For technique, from sustained compression to pin and stretch, see trigger point therapy techniques. The debate about rollers and fascia is covered in Behm & Wilke, 2019.
Where next
Last reviewed October 2026. Summaries are ours; read the original paper before citing it. Know a study we should add? Tell us.
