title: A randomized trial to determine the duration of analgesia following a 15- and a 30-minute application of acupuncture-like TENS on patients with chronic low back pain.
abstract: BACKGROUND
  Acupuncture-like TENS (AL-TENS) has been shown to produce prolonged pain relief, but no study has yet investigated its duration on a population suffering from chronic low back pain (CLPB).
  
  
  OBJECTIVE
  Our objective was to quantify the duration and magnitude of analgesia induced by a 15- or 30-minute application of AL-TENS.
  
  
  METHODS
  We recruited a sample of 11 participants presenting with CLBP and conducted a randomized, crossover study, where participants were given AL-TENS for 15 and 30 minutes on two separate occasions. The pain intensity of their CLBP was assessed with a visual analogue scale before, during, and after AL-TENS applications. Magnitude and duration of analgesia were determined for each subject and for both AL-TENS application times.
  
  
  RESULTS
  The AL-TENS applications induced a clinically and statistically significant (p = 0.003) analgesia in all participants. Median duration of analgesia was 9 hours and 10 hours 30 minutes following the 15- and 30-minute AL-TENS applications, respectively; this 1.5-hour difference was not statistically significant (p = 0.55). Furthermore, we observed no significant difference in the magnitude of analgesia between both applications of AL-TENS (p > 0.56), suggesting that the duration of application of AL-TENS does not influence the magnitude of analgesia.
  
  
  CONCLUSIONS
  Our results suggest that clinicians could use a 15-minute AL-TENS application to provide significant analgesia in patients presenting with low back pain since if provides a comparable analgesia versus a 30-minute application.
authors.affiliation: a Faculty of Medicine and Health Sciences , Université de Sherbrooke , Sherbrooke , QC , Canada.|b Centre de Recherche Clinique du CHUS , Sherbrooke , QC , Canada.
authors.forename: Yannick
authors.initials: Y
authors.lastname: Tousignant-Laflamme
authors.affiliation: a Faculty of Medicine and Health Sciences , Université de Sherbrooke , Sherbrooke , QC , Canada.
authors.forename: Claudia
authors.initials: C
authors.lastname: Laroche
authors.affiliation: a Faculty of Medicine and Health Sciences , Université de Sherbrooke , Sherbrooke , QC , Canada.
authors.forename: Christine
authors.initials: C
authors.lastname: Beaulieu
authors.affiliation: a Faculty of Medicine and Health Sciences , Université de Sherbrooke , Sherbrooke , QC , Canada.
authors.forename: Ann-Julie
authors.initials: AJ
authors.lastname: Bouchard
authors.affiliation: a Faculty of Medicine and Health Sciences , Université de Sherbrooke , Sherbrooke , QC , Canada.
authors.forename: Sabrina
authors.initials: S
authors.lastname: Boucher
authors.affiliation: a Faculty of Medicine and Health Sciences , Université de Sherbrooke , Sherbrooke , QC , Canada.
authors.forename: Mélanie
authors.initials: M
authors.lastname: Michaud-Létourneau
mesh_terms: D059350:Chronic Pain / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D018592:Cross-Over Studies; D015671:Electroacupuncture; D006801:Humans; D017116:Low Back Pain / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D059408:Pain Management / Q000379:methods*; D010147:Pain Measurement; D011792:Quebec; D013997:Time Factors; D004561:Transcutaneous Electric Nerve Stimulation; D016896:Treatment Outcome
keywords: Analgesia; TENS; chronic low back pain; physiotherapy