title: Comparative analgesic effects of H-wave therapy and transcutaneous electrical nerve stimulation on pain threshold in humans.
abstract: OBJECTIVE
  To assess the comparative analgesic efficacy of H-wave therapy (HWT) and transcutaneous electrical nerve stimulation (TENS) using a mechanical model of pain threshold measurement.
  
  
  METHODS
  Forty-eight healthy human volunteers (24 women, 24 men) were recruited and randomly assigned into one of six experimental groups; control, HWT (placebo, 2Hz, or 60Hz), or TENS (placebo or 110Hz). For each subject, mechanical pain threshold (MPT) measurements were recorded at three standardized recording points marked on the dorsal web space of the dominant hand. Two MPT measurements were recorded at each point at the following time intervals: before treatment was initiated (baseline), after each of three consecutive 10-minute periods of stimulation (HWT or TENS), and at four intervals within 30 minutes after stimulation. In the control and placebo groups MPT measurements were recorded at similar time intervals.
  
  
  RESULTS
  Difference scores, calculated from patients' baseline values, were analyzed by ANOVA for each of the three recording points. Although results showed a significant increase in MPT levels in all three stimulation groups when compared with their relative placebo (indicating a hypoalgesic effect), no differences were observed between the different modalities or HWT frequencies. Significant hypoalgesia continued for 5 minutes after stimulation.
  
  
  CONCLUSIONS
  The findings showed that HWT and TENS provided localized hypoalgesia during stimulation and for up to 5 minutes after it. No frequency- or modality-specific effects were observed between the groups.
authors.affiliation: Rehabilitation Sciences Research Group, School of Health Sciences, University of Ulster at Jordanstown, Northern Ireland, UK.
authors.forename: B C
authors.initials: BC
authors.lastname: McDowell
authors.forename: K
authors.initials: K
authors.lastname: McCormack
authors.forename: D M
authors.initials: DM
authors.lastname: Walsh
authors.forename: D G
authors.initials: DG
authors.lastname: Baxter
authors.forename: J M
authors.initials: JM
authors.lastname: Allen
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D017288:Pain Threshold / Q000502:physiology*; D004561:Transcutaneous Electric Nerve Stimulation / Q000379:methods*; D016896:Treatment Outcome