Effect of needle selection on battlefield acupuncture tolerance and pain reduction: an exploratory randomized controlled trial

Introduction: There has been limited research comparing the different types of needles used for auricular battlefield acupuncture (BFA). The aim of this exploratory study was to determine the feasibility of examining whether there are differences in needle tolerance and/or pain reduction between different needle types. Methods: We conducted an unblinded, exploratory, randomized controlled trial in human subjects with complaints of acute or chronic pain. We randomized 30 patients to receive BFA with ASP needles, disposable needles of 15 mm length or Pyonex needles (n = 10 per group). Differences in Defense and Veteran Pain Rating Scale (DVPRS) scores and needle tolerance questionnaire responses by treatment group and follow-up time point (baseline, 10 min, 24 h and 1 week) were assessed using random effects regression and ordinal logistics models. Results: A difference in needle tolerance by treatment group was observed for pain at the site(s) of needling (p = 0.002), which was lower for 15-mm needles (odds ratio (OR) = 0.12, p = 0.005) than for ASP needles, but not significantly different for Pyonex versus ASP (OR = 1.45, p = 0.525). There were no difference in overall patient satisfaction, dizziness, bruising, fatigue or headaches between the three BFA needle groups (p = 0.190). No statistically significant associations were observed between treatment group and clinical characteristics (all p > 0.05). DVPRS scores significantly declined after treatment (interaction beta coefficient (β) = −1.40, p < 0.001) across all treatment groups. Declines were also observed post treatment for DVPRS questions 1 (β = −1.23, p = 0.003), 3 (β = −1.23, p < 0.002) and 4 (β = −1.10, p = 0.002). A decline over time after treatment was also observed for DVPRS question 1 (β = −0.15, p = 0.014), 3 (β = −0.12, 0.049) and 4 (β = −0.13, p = 0.016) but was not DVPRS overall score. No significant interactions by treatment group were observed. Conclusion: Testing BFA needle types against each other was feasible and the interventions were acceptable to subjects. Through a post hoc power calculation, this study provides a greater understanding of the number of patients that would be needed to more definitively assess for potential differences in effectiveness (pain reduction) between various types of needles in BFA. Trial registration number: NCT04464954 (ClinicalTrials.gov).