Effects of adding electro-massage to manual therapy for the treatment of individuals with myofascial temporomandibular pain: a randomized controlled trial

Objective: To evaluate the effect of the addition of dynamic cervical electrical stimulation (electro-massage, ES) to manual therapy (MT), compared to MT by itself, in individuals with myofascial temporomandibular pain. Methodology: A total of 46 participants with bilateral myofascial temporomandibular pain for at least three months were distributed into two groups. Group 1 (n=21) received local MT consisting of soft tissue mobilization and release techniques over the neck and temporomandibular regions. Group 2 (n=25) received an ES procedure in the cervical region combined with the same intervention as group 1. All participants underwent a 2-week protocol. The primary outcomes were pain intensity (Visual Analogue Scale), pressure pain threshold (PPT) at the masseter and upper trapezius muscles (algometer), and pain-free vertical mouth opening (manual gauge). The secondary outcome was active cervical range-of-movement. Measurements were taken at baseline, immediately after intervention, and at a 4-week follow-up. Results: The ANOVA revealed significant changes over group*time, with better results for group 2 (large effect sizes) regarding pain intensity (p< 0.001; eta 2>0.14), pressure pain sensitivity and mouth opening (p<0.001; eta 2>0.14). Similar findings were observed for active cervical range-of-movement in all directions (p<0.001; eta 2>0.14), except rotation (p >= 0.05). Conclusion: Electrical stimulation therapy over the cervical region combined with a MT protocol over the neck and temporomandibular joint shows better clinical benefits than MT by itself in subjects with myofascial temporomandibular pain.