Research article

Treatment of chronic back pain by sensory discrimination training. A Phase I RCT of a novel device (FairMed) vs. TENS

Karen L Barker^1,2 , Christopher J Elliott¹ , Catherine M Sackley³ and Jeremy CT Fairbank⁴

¹Physiotherapy Research Unit, Nuffield Orthopaedic Centre NHS Trust, Oxford, OX3 7LD, UK

²School of Health Sciences, University of Birmingham, Birmingham, B15 2TT, UK

³Department of Primary Care and General Practice, University of Birmingham Birmingham, B15 2TT, UK

⁴Nuffield Department of Orthopaedic Surgery, Nuffield Orthopaedic Centre, Oxford, OX3 7LD, UK

author email corresponding author email

BMC Musculoskeletal Disorders 2008, 9:97doi:10.1186/1471-2474-9-97

Published:	28 June 2008

Abstract

Background

The causes of chronic low back pain (CLBP) remain obscure and effective treatment of symptoms remains elusive. A mechanism of relieving chronic pain based on the consequences of conflicting unpleasant sensory inputs to the central nervous system has been hypothesised. As a result a device was generated to deliver sensory discrimination training (FairMed), and this randomised controlled trial compared therapeutic effects with a comparable treatment modality, TENS.

Methods

60 patients with CLBP were recruited from physiotherapy referrals to a single-blinded, randomised controlled, non-inferiority trial. They were randomised to receive either FairMed or TENS and asked to use the allocated device for 30 minutes, twice a day, for 3 weeks. The primary outcome variable measured at 0 and 3 weeks was pain intensity measured using a visual analogue scale averaged over 7 days. Secondary outcome measures were Oswestry Disability Index, 3 timed physical tests, 4 questionnaires assessing different aspects of emotional coping and a global measure of patient rating of change. Data were analysed for the difference in change of scores between groups using one-way ANOVA.

Results

Baseline characteristics of the two groups were comparable. The primary outcome, change in pain intensity (VAS) at 3 weeks showed a mean difference between groups of -0.1, (non significant p = 0.82). The mean difference in change in ODI scores was 0.4; (non significant p = 0.85). Differences in change of physical functioning showed that no significant difference in change of scores for any of these test (p = 0.58 – 0.90). Changes in scores of aspects of emotional coping also demonstrated no significant difference in change scores between the groups (p = 0.14 – 0.94).

Conclusion

FairMed was not inferior to TENS treatment.

The findings have implications for further research on current chronic pain theories and treatments. Further work to explore these mechanisms is important to expand our understanding of chronic pain and the role of neuro-modulation.

Trial Registration

UKCRN Study ID 3321