Patients with tension-type or migraine headaches often exhibit myofascial trigger points. The involvement of these trigger points in the pathophysiology of these conditions is not well understood, according to the findings of a report published in The Journal of Headache and Pain. Ultrasound elastography may be best-suited for use as a diagnostic tool for trigger point detection in these patient populations.
Myofascial trigger points are thought to play a role in the pathophysiology of pain conditions, including headache disorders, but evidence supporting this notion is unclear. Investigators reviewed the literature examining the role of myofascial trigger points in tension-type headache and migraine as well as diagnostic imaging techniques used in conjunction with the gold standard of palpation.
A number of different imaging methods have been used to evaluate myofascial trigger points, including microdialysis, magnetic resonance imaging, infrared thermography, electromyography (EMG), and ultrasound. Of these options, ultrasound appeared to offer the most promise as a diagnostic tool, particularly if elastography by Doppler variance imaging was used. EMG was considered the next best option. The reviewers caution that the validation of ultrasound as a diagnostic tool for evaluating the presence of myofascial trigger points in patients with primary headache will require further studies.
A high prevalence of active trigger points was found in patients with tension-type headache supporting the hypothesis that this condition may arise from peripheral mechanisms. In addition, the presence of active trigger points in the pericranial muscles of patients with tension-type headache, which is often accompanied by reduced pain pressure thresholds, suggests that central sensitization may be involved in the development of these disorders. However, the rate of myofascial trigger points was found to increase with age in several studies, suggesting that their accumulation occurs over time, secondary to tension-type headaches vs being involved in their pathophysiology.
Patients with migraine headache were found to have a high prevalence of myofascial trigger points in the studies reviewed, with reports of palpation triggering acute attacks. Although interventions at trigger point sites (eg, local anesthetic infiltration, botulinum toxin injection) were found to be effective in treating migraines, placebo-controlled trials are warranted to validate such approaches.
“The results of the provocation and intervention studies support the hypothesis of a
trigemino-cervical-complex pathophysiology model in both migraine and [tension-type headache],” concluded the authors, who recommended that future research focus on trials with larger and more homogenous cohorts, and studies examining the use of ultrasound elastography as a diagnostic tool for myofascial trigger points in tension-type headache and migraine.
Conflict of Interest Disclosures
One of the study authors received travel grants or speaking fees from Pfizer, Autonomic Technologies and Novartis.
Do TP, Heldarskard GF, Kolding LT, Hvedstrup J, Schytz HW. Myofascial trigger points in migraine and tension-type headache. J Headache Pain. 2018;19(1):1-17. doi:10.1186/s10194-018-0913-8