One of the numerous conditions chiropractors, osteopaths, and other manual therapists claim to treat effectively is tension-type headache (TTH). For this purpose, they (in particular, chiropractors) often use high-velocity, low-amplitude manipulations of the neck. They do so despite the fact that the evidence for these techniques is less than convincing.
This systematic review evaluated the evidence about the effectiveness of manual therapy (MT) on pain intensity, frequency, and impact of pain in individuals with tension-type headache (TTH).
Medline, Embase, Scopus, Web of Science, CENTRAL, and PEDro were searched in June 2020. Randomized clinical trials that applied MT not associated with other interventions for TTH were selected. The level of evidence was synthesized using GRADE, and Standardized Mean Differences (SMD) were calculated for meta-analysis.
Fifteen studies were included with a total sample of 1131 individuals. The analyses show that high-velocity, low-amplitude techniques were not superior to no treatment in reducing pain intensity (SMD = 0.01, low evidence) and frequency (SMD = -0.27, moderate evidence). Soft tissue interventions were superior to no treatment in reducing pain intensity (SMD = -0.86, low evidence) and frequency of pain (SMD = -1.45, low evidence). Dry needling was superior to no treatment in reducing pain intensity (SMD = -5.16, moderate evidence) and frequency (SMD = -2.14, moderate evidence). Soft tissue interventions were not superior to no treatment and other treatments on the impact of headache.
The authors concluded that manual therapy may have positive effects on pain intensity and frequency, but more studies are necessary to strengthen the evidence of the effects of manual therapy on subjects with tension-type headache. Implications for rehabilitation soft tissue interventions and dry needling can be used to improve pain intensity and frequency in patients with tension type headache. High velocity and low amplitude thrust manipulations were not effective for improving pain intensity and frequency in patients with tension type headache. Manual therapy was not effective for improving the impact of headache in patients with tension type headache.
So, this review shows that:
- soft tissue interventions are better than no treatment,
- dry needling is better than no treatment.
These two results fail to impress me. Due to a placebo effect, almost any treatment should be better than no therapy at all.
ALMOST, because high-velocity, low-amplitude techniques were not superior to no treatment in reducing the intensity and frequency of pain. This, I feel, is an important finding that needs an explanation.
As it is only logical that high-velocity, low-amplitude techniques must also produce a positive placebo effect, the finding can only mean that these manipulations also generate a negative effect that is strong enough to cancel the positive response to placebo. (In addition, they can also cause severe complications via arterial dissections, as discussed often on this blog.)
Perhaps; let me, therefore, put it simply and use the blunt words of a neurologist who once was quoted saying this:
DON’T LET THE BUGGARS TOUCH YOUR NECK!