Repetitive neuromuscular magnetic stimulation (rNMS) in children and adolescents with post-traumatic headache: a retrospective chart review

Background Post-traumatic headaches (PTH) are a very common health issue after traumatic brain injury (TBI). In addition, patients frequently experience discomfort and pain in the neck region. Regarding the pathophysiology of PTH, the trigeminal-cervical complex (TCC) is of high relevance. Repetitive neuromuscular magnetic stimulation (rNMS) targeting the upper trapezius muscle (UTM) may represent a novel treatment approach, having demonstrated beneficial effects in primary headache disorders. This retrospective analysis aimed to explore its effects in children and adolescents affected by PTH. Methods rNMS intervention comprised 5 to 6 sessions within 2 to 3 weeks with bilateral stimulation cycles (15 min, 20 Hz, 7,420 stimuli per side, oscillating intervals 7 s ON/10 s OFF), flanked by baseline and follow-up assessments at 94.9 ± 35.6 days after the last session (FU): documentation of headache characteristics (frequency, duration, intensity) and pressure pain thresholds (PPT) by algometry above the UTM. Results 17 patients (aged 14.0 ± 2.0 years, 13 females) received a total of 26 rNMS interventions with most patients ( n = 10) receiving one, 6 patients two, and one patient 4 rNMS treatment blocks. Treatment-level analyses included all treatment blocks. Additional patient-level sensitivity analyses were restricted to the first treatment block per patient. Headache frequency significantly decreased from 21.8 ± 10.2 to 12.6 ± 11.4 days/month on FU ( p = 0.001). On the individual level, a ≥ 25% reduction in headache frequency was observed after 16 rNMS interventions (61.5%), and a ≥ 75% reduction after 8 rNMS interventions (30.8%). Maximum and minimum headache intensity significantly decreased from 7.3 ± 2.2 to 6.0 ± 2.3 and 4.9 ± 2.3 to 4.0 ± 2.5 at FU, respectively ( p = 0.013; p = 0.027). No significant change regarding the duration of headache episodes was observed. PPT above the UTM significantly increased ( p < 0.001) from baseline to last rNMS session and remained increased until FU. Patient-level sensitivity analyses of only the first rNMS treatment blocks showed a comparable pattern of reductions in headache frequency and intensity as well as increases in PPT. Conclusions In this retrospective cohort, rNMS was associated with reductions in headache frequency and intensity and with increased PPT above the UTM. Given the small sample size, the lack of a control or sham condition, and the multimodal treatment setting, these findings should be considered preliminary and hypothesis-generating. Prospective controlled studies are warranted to determine the efficacy and specific clinical role of rNMS in pediatric PTH, a headache disorder that remains understudied in clinical research.