Found this systematic review on spinal manipulative therapy (SMT) and chronic headaches. Though the authors note that the research isn’t based on strong studies this is their conclusion:
SMT appears to have a better effect than massage for cervicogenic headache. It also appears that SMT has an effect comparable with commonly used first-line prophylactic prescription medications for tension-type headache and migraine headache. This conclusion
rests on a few trials of adequate methodological quality. Before any firm conclusions can be drawn, further testing should be done in rigorously designed, executed, and analyzed trials with followup periods of sufficient length.
If you have headaches then spinal manipulation or chiropractic adjustments can be an appropriate form of treatment for you. In the following research paper you will see that spinal manipulation was more effective for reducing headaches than mobilization. You should also note that a long course of treatment was not necessary. Six to eight visits were performed to show significant effects.
Exercises were not performed by those who received manipulation. You should note that there are other papers that indicate that manipulation and exercise is more effective than with manipulation alone.
Here is the abstract. You can find the full version through the link.
Source: Upper cervical and upper thoracic manipulation versus mobilization and exercise in patients with cervicogenic headache: a multi-center randomized c… – PubMed – NCBI
Although commonly utilized interventions, no studies have directly compared the effectiveness of cervical and thoracic manipulation to mobilization and exercise in individuals with cervicogenic headache (CH). The purpose of this study was to compare the effects of manipulation to mobilization and exercise in individuals with CH.
One hundred and ten participants (n = 110) with CH were randomized to receive both cervical and thoracic manipulation (n = 58) or mobilization and exercise (n = 52). The primary outcome was headache intensity as measured by the Numeric Pain Rating Scale (NPRS). Secondary outcomes included headache frequency, headache duration, disability as measured by the Neck Disability Index (NDI), medication intake, and the Global Rating of Change (GRC). The treatment period was 4 weeks with follow-up assessment at 1 week, 4 weeks, and 3 months after initial treatment session. The primary aim was examined with a 2-way mixed-model analysis of variance (ANOVA), with treatment group (manipulation versus mobilization and exercise) as the between subjects variable and time (baseline, 1 week, 4 weeks and 3 months) as the within subjects variable.
The 2X4 ANOVA demonstrated that individuals with CH who received both cervical and thoracic manipulation experienced significantly greater reductions in headache intensity (p < 0.001) and disability (p < 0.001) than those who received mobilization and exercise at a 3-month follow-up. Individuals in the upper cervical and upper thoracic manipulation group also experienced less frequent headaches and shorter duration of headaches at each follow-up period (p < 0.001 for all). Additionally, patient perceived improvement was significantly greater at 1 and 4-week follow-up periods in favor of the manipulation group (p < 0.001).
Six to eight sessions of upper cervical and upper thoracic manipulation were shown to be more effective than mobilization and exercise in patients with CH, and the effects were maintained at 3 months.