Chronic pain can interfere with the cortical representation of a painful body part. This disruption might play a role in maintaining the individual’s pain. Tactile acuity training has been employed to normalise cortical representation and reduce pain in certain pain conditions. However, there is a shortage of evidence for the effectiveness of this intervention for chronic low back pain (CLBP). The primary objective of this study was to inform the development of a fully powered randomised controlled trial (RCT) by providing preliminary data on the effect of tactile acuity training on pain and function in individuals with CLBP. The secondary objective was to procure qualitative feedback about the intervention. In this mixed-methods pilot RCT 15 individuals were randomly separated into either an intervention (tactile acuity training) or a placebo group (sham tactile acuity training). All participants received 3 sessions of acuity training (intervention or sham) from a physiotherapist and were requested to undertake daily acuity home training assisted by an informal carer (friend/relative). All participants also received usual care physiotherapy. The primary outcome measures were pain (0-100visual analogue scale (VAS)) and function (Roland Morris Disability Questionnaire (RMDQ)). Participants and their informal carers were invited to a focus group to provide feedback on the intervention. The placebo group improved by the greatest magnitude for both outcome measures, although there wasn’t any statistically significant difference (Mean difference (95%CI), p-value) between groups for change in pain (25.6 (-0.7 to 51.9), p = 0.056) or function (2.2 (-1.6 to 6.0), p = 0.237). Comparing the number of individuals achieving a minimally clinically significant improvement, the placebo group had superior results for pain with all participants achieving ≥30% improvement compared to only a third of the intervention group (6/6 vs. 3/9, p = 0.036). Qualitatively, participants reported that needing an informal carer was a substantial hindrance to the home training component of the study.
This pilot RCT did not find tactile acuity training to be more effective than sham tactile acuity training for function and found it to be less effective for pain in individuals with CLBP. That the intervention could not be self-applied was a significant hindrance to its use.