Spinal manipulation may be an effective therapy for reducing migraine days and pain intensity, although large-scale and methodologically rigorous randomized controlled trials (RCTs) are warranted, according to a study published in Headache.
This systematic review and meta-analysis of published RCTs evaluated the evidence for using spinal manipulation as an integrative or alternative therapy to reduce migraine pain and disability. Clinical trials assessing spinal manipulation and migraine-related outcomes were found by searching PubMed and the Cochrane Library databases through April 2017 using the search terms migraine, spinal manipulation, chiropractic, osteopathic, and manual therapy. The effect sizes (Hedges’ g) and heterogeneity (I²) for migraine pain, days, and disability were estimated using meta-analytic methods, and the Cochrane Risk of Bias tool was used to examine the methodological quality of retrieved studies.
Six RCTs (pooled n=677; range n=42-218) were found to be eligible for meta-analysis. The duration of intervention ranged from 2 to 6 months with migraine days as the primary outcome and migraine disability and pain/intensity as secondary outcomes. The methodological quality varied across the trials with some receiving unclear or high bias scores for methodological features, such as blinding, adherence, and completeness of outcome data. The 1 RCT performed only among patients with chronic migraine was excluded due to the high levels of heterogeneity (I² ratio 93.80%) seen with all 6 studies included in the meta-analysis. Heterogeneity across the remaining 5 studies was low (Q statistic 3.61; P =.72; I² ratio 0). Spinal manipulation reduced migraine days with an overall small effect size using both a fixed-effects model and a random-effects model used to perform a sensitivity analysis (Hedges’ g -0.35; 95% CI, -0.53 to -0.16; P <.001). Spinal manipulation also had a greater impact on the reduction of migraine pain/intensity with an overall small effect size (Hedges’ g -0.28; 95% CI, -0.46 to -0.09; P =.004) from a fixed effects meta-analysis (Q=3.26, P =.77; I²=0). This effect was similar when analyses were restricted to active control groups (Hedges’ g -0.23; 95% CI, -0.46 to 0; P =.050) or to passive controls t (Hedges’ g -0.36; 95% CI, -0.67 to -0.04; P =.027).
Study investigators conclude, “Results from this preliminary meta-analysis suggest that spinal manipulation may reduce migraine days and pain/intensity. However, variation in study quality makes it difficult to determine the magnitude of this effect. Methodologically rigorous, large-scale RCTs are warranted to better inform the evidence base for the role of spinal manipulation in integrative models of care provided by chiropractors, physical therapists, and osteopathic physicians as a treatment for migraine.”
Rist PM, Hernandez A, Bernstein C, et al. The impact of spinal manipulation on migraine pain and disability: a systematic review and meta-analysis [published online March 14, 2019]. Headache. doi: 10.1111/head.13501