We offer photobiomodulation at this clinic — low-level laser and LED light applied to tissue — for several musculoskeletal problems. Low back pain is not one of them.
This is a post about why. It uses the same evidence we used to make the decision, including the evidence that points the other way.
The review that settled it for us
In 2020, the Journal of Physiotherapy published a systematic review by Tomazoni and colleagues (PMID 32680739). Twelve randomized controlled trials. 1,046 participants. Most of the included trials were judged to be at low risk of bias — which matters, because it closes the usual escape hatch. Nobody can say the trials were too sloppy to detect a real effect.
The authors’ conclusion, word for word:
"Current evidence does not support the use of PBMT to decrease pain and disability in people with non-specific LBP."
"Non-specific" low back pain is the common kind — the kind where scans do not identify one structure clearly responsible for the pain. It is most low back pain. It is almost certainly what you have if you are reading this.
The detail that makes this hard to dismiss
Look at who wrote it.
Jan Magnus Bjordal and Ernesto Cesar Leal-Junior are among the most published researchers in photobiomodulation. Bjordal’s name sits on the papers this field reaches for when it wants to make its strongest case — including Bjordal and colleagues’ 2008 review of low-level laser for tennis elbow in BMC Musculoskeletal Disorders (PMID 18510742), which pooled 13 trials and 730 patients and found that 904 nm light applied directly to the tendon produced 17.2 mm of pain relief on a 100 mm scale (95% CI 8.5 to 25.9, p=0.0001).
Those same researchers looked at their own field’s application to low back pain and published a negative result.
That matters for a reason that has nothing to do with laser physics. Every incentive in a research career points toward positive findings: they publish more easily, they attract funding, they build a field. When the people with the most to gain from a positive answer are the ones reporting the negative one, the finding carries a weight that an outsider’s critique never would.
It also removes the most common way a clinic can wave off an inconvenient review — the authors didn’t understand the dosing. These authors wrote much of the dosing literature.
That is what scientific integrity looks like in practice. It is unglamorous and it costs the people who do it something.
The counterpoint, stated fairly
There is a review pointing the other way, and you should see it.
Huang and colleagues, Arthritis Research & Therapy, 2015 (PMID 26667480) pooled 7 randomized trials and found a pain difference of −13.57 mm on a 100 mm visual analog scale (95% CI −17.42 to −9.72), with I² = 0%.
Two things about that result deserve plain explanation.
I² = 0% is unusual and it is a point in the review’s favor. I² measures how much the individual trials disagree with each other. Zero means they agreed almost perfectly. That is not nothing.
And there was no significant effect on disability or on range of motion. Pain scores moved. What people could actually do did not.
How to weigh 12 trials against 7
This is the part most clinic websites skip, so here is our actual reasoning.
1. Size and recency. The 2020 review includes 12 trials to the earlier review’s 7, and covers the literature five years further on. It is not a different question answered differently; it is a larger version of the same question, including the trials published after 2015.
2. Risk of bias was assessed and reported. Tomazoni’s group rated the methodological quality of what they pooled and found most of it strong. A pooled number is only as good as the studies feeding it, and reviews that pool without weighing quality can produce effect estimates driven mostly by the weakest trials in the set.
3. The outcome that matters did not move — in either review. Take Huang entirely at face value and you still get pain scores shifting with no change in disability or range of motion. That is not a technicality. People come to us for low back pain because they have stopped lifting their kids, stopped sleeping through the night, stopped a job task. A number on a scale that moves while none of that changes is not the thing we were asked to help with.
4. The direction of travel. When a body of evidence grows and the effect estimate shrinks toward zero, that pattern usually means the early signal was small-study noise rather than a treatment that stopped working. It is one of the most reliable patterns in clinical research.
None of this makes the 2015 review dishonest or the 13.57 mm figure fabricated. Two competent teams read overlapping literatures and reached different conclusions. We go with the larger, newer, bias-assessed one — and we tell you the other one exists, because you cannot judge our reasoning if we hide half of it.
Why a negative result here is not a negative result everywhere
Light does not travel far through tissue. It scatters and is absorbed within millimeters to a couple of centimeters depending on wavelength. A tendon at the outside of the elbow sits close to the surface. The structures implicated in low back pain sit under a substantial layer of paraspinal muscle and, for many people, fat.
That is a plausible explanation for the difference. It is not a demonstrated one, and we are not going to present it as though it were.
What the same 2008 tennis elbow review does show clearly is that details decide outcomes: 820 nm, 830 nm and 1064 nm showed no significant effect, and irradiating acupuncture points instead of the tendon itself produced negative results. "Laser therapy" is not one thing.
Where the evidence is better, we say so with the same specificity. For knee osteoarthritis, Stausholm and colleagues in BMJ Open, 2019 (PMID 31662383) pooled 22 trials and 1,063 patients: 14.23 mm pain reduction overall (95% CI 7.31 to 21.14), 18.71 mm when doses followed WALT recommendations against only 6.34 mm when they did not, with a subgroup difference of p=0.02. Heterogeneity in that review was very high (I² = 93–95%), which we also state every time.
And the widest view available: an umbrella review by Son and colleagues in Systematic Reviews, 2025 (PMID 40770824) covering 15 meta-analyses, 204 randomized trials and more than 9,000 participants across 35 outcomes concluded that no outcome was supported by high certainty of evidence. That is the honest ceiling on this entire field, and it applies to the treatments we do offer as much as the ones we don’t.
What we do instead for chronic low back pain
The alternative is not another device. It is slower and less interesting than that.
- A long first assessment. What provokes it, what positions ease it, what you have stopped doing, how it behaves across a day, how you are sleeping, and whether any previous imaging changed anything about your care.
- Screening for the things that need a different pathway — the symptoms that mean an imaging referral or a specialist rather than a rehabilitation plan.
- Graded activity. A starting level you can complete without a flare-up, increased on a schedule rather than according to how the morning feels. Consistency beats intensity here.
- Progressive loading for the hips, trunk and legs, built around what you actually need to do at work and at home.
- The drivers nobody bills for: sleep debt, deconditioning, apprehension about moving, and a work or training pattern that keeps re-provoking the problem.
- Coordination with a physical therapist. If you already have one, keep them. We would rather add to that plan than duplicate it.
- Numbers at every visit — a pain score and a function measure — reviewed formally at six weeks. If the numbers are flat, the plan changes.
We are deliberately not attaching effect sizes to that list. This article’s citation set is about light therapy, and we do not quote evidence we have not put in front of you. If you want to see the trial data behind exercise-based care for low back pain, ask at your visit and we will go through it together.
It is worth noticing that this plan involves no device, and that we cannot charge you for a machine we are not switching on.
Why we published this
Because a clinic that only tells you what works is not telling you enough to make a decision.
Any list of treatments looks convincing when the failures are edited out. The useful question is not "what does this clinic offer?" but "what does this clinic decline to offer, and can they show you the study that made them decline it?" We would rather you ask us that question than not think to ask it.
If someone offers you light therapy for low back pain, they are not necessarily acting in bad faith — but you now know the strongest review of the question, who wrote it, what it found, and what the best counterargument looks like. That is enough to have a real conversation about it, with us or with anyone else.
This article is general education, not medical advice, and it is not a substitute for evaluation by a qualified clinician. It does not establish a physician–patient relationship. Individual results vary, and the studies described report group averages rather than what any one person should expect. Treatments discussed may not be FDA-cleared or approved for the conditions mentioned; where that is the case it is stated in the text. Talk to your own physician before starting, stopping or changing any treatment.
