PainSci commentary on Oliveira-Campelo 2013: ?This page is one of thousands in the PainScience.com bibliography. It is not a general article: it is focused on a single scientific paper, and it may provide only just enough context for the summary to make sense. Links to other papers and more general information are provided wherever possible.
This complicated study begins with the strangely overconfident assumption that asymptomatic upper trapezius trigger points in 117 volunteers were “due to computer work.”
What a shame they stuck to asymptomatic people. That’s really unfortunate. In their words, that is “not representative of the population often seen in clinics.” No, not at all. We need to study treatment of people who need treatment.
The potential power of a study with so many subjects is also greatly undermined by an overly complicated design. They compared three different manual techniques: ischemic compression, stretching, muscle energy technique, plus two placebo groups (no treatment, and a sham). Thumbs up for actual control groups, but thumbs down for too much comparing. If only they had stuck to testing just ischemic compression! But five groups is too many dicks on the dance floor, statistically speaking.
They were looking for changes in both the sensitivity of the trigger point and neck range of motion. They made their measurements before treatment, right after, a day after, and a week later (which is longer-term follow-up than most similar studies). Charmingly, their abstract reports a “large” initial effect size for all three treatments (it’s practically unheard of to report effect size rather than statistical significance). After a day, only the ischemic group was still doing well.
So clearly they are reporting a robust positive result. Unfortunately, they did not publish their actual results, only aggregate scoring, which makes it very difficult for me to trust. The more complex the study, the more opportunities there are to play with the crunching and presentation of the data to fit the biases of the researchers. The closest thing we have to an antidote to this is the data itself. This paper presents a great deal of information without telling me what the actual, specific results of their measurements were. Instead, they are asking me to take their word for it that the data added up to “good news.” That’s kind of a deal-breaker for me.
And then there’s the fact that all these subjects were asymptomatic — not the right kind of test subjects in the first place.
~ Paul Ingraham
original abstract †Abstracts here may not perfectly match originals, for a variety of technical and practical reasons. Some abstacts are truncated for my purposes here, if they are particularly long-winded and unhelpful. I occasionally add clarifying notes. And I make some minor corrections.
OBJECTIVE: The purpose of this study was to investigate effects of different manual techniques on cervical ranges of motion and pressure pain sensitivity in subjects with latent trigger point of the upper trapezius muscle.
METHODS: One hundred seventeen volunteers, with a unilateral latent trigger point on upper trapezius due to computer work,«interesting assumption» were randomly divided into 5 groups «that is a lot of groups»: ischemic compression (IC) group (n=24); passive stretching group (n=23); muscle energy technique group (n=23); and 2 control groups, wait-and-see group (n=25) and placebo group (n=22). Cervical spine range of movement was measured using a cervical range of motion instrument as well as pressure pain sensitivity by means of an algometer and a visual analog scale. Outcomes were assessed pretreatment, immediately, and 24 hours after the intervention and 1 week later by a blind researcher. A 4×5 mixed repeated-measures analysis of variance was used to examine the effects of the intervention and Cohen d coefficient was used.
RESULTS: A group-by-time interaction was detected in all variables (P<.01), except contralateral rotation. The immediate effect sizes «reporting effect size in an abstract? pinch me, I’m dreaming!» of the contralateral flexion, ipsilateral rotation, and pressure pain threshold were large for 3 experimental groups. Nevertheless, after 24 hours and 1 week, only IC group maintained the effect size.
CONCLUSIONS: Manual techniques on upper trapezius with latent trigger point seemed to improve the cervical range of motion and the pressure pain sensitivity. These effects persist after 1 week in the IC group.
This page is part of the PainScience BIBLIOGRAPHY, which contains plain language summaries of thousands of scientific papers & others sources. It’s like a highly specialized blog. A few highlights:
- Exercise and education versus saline injections for knee osteoarthritis: a randomised controlled equivalence trial. Bandak 2022 Ann Rheum Dis.
- Association of Lumbar MRI Findings with Current and Future Back Pain in a Population-based Cohort Study. Kasch 2022 Spine (Phila Pa 1976).
- A double-blinded randomised controlled study of the value of sequential intravenous and oral magnesium therapy in patients with chronic low back pain with a neuropathic component. Yousef 2013 Anaesthesia.
- Is Neck Posture Subgroup in Late Adolescence a Risk Factor for Persistent Neck Pain in Young Adults? A Prospective Study. Richards 2021 Phys Ther.
- Sudden amnesia resulting in pain relief: the relationship between memory and pain. Choi 2007 Pain.