Tactile acuity training for patients with chronic low back pain: a pilot randomised controlled trial

Abstract

Background: Chronic pain can disrupt the cortical representation of a painful body part. This disruption may play a role in maintaining the individual's pain. Tactile acuity training has been used to normalise cortical representation and reduce pain in certain pain conditions. However, there is little evidence for the effectiveness of this intervention for chronic low back pain (CLBP). The primary aim 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 aim was to obtain qualitative feedback about the intervention.

Methods: In this mixed-methods pilot RCT 15 individuals were randomised to 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 facilitated 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.

Results: The placebo group improved by the greatest magnitude for both outcome measures, but there was no 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 better outcomes 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 considerable barrier to the home training component of the study.

Conclusions: This pilot RCT found tactile acuity training to be no more effective than sham tactile acuity training for function and less effective for pain in individuals with CLBP. That the intervention could not be self-applied was a considerable barrier to its use.

Trial registration isrctn: ISRCTN98118082.

Figure 1

Participant flow chart. This figure shows the pathway of recruitment and retention of participants.

Figure 2

Function levels pre and post treatment. This figure shows the function levels, as measured by the Roland Morris Disability Questionnaire (RMDQ) pre and post treatment for both groups. * indicates a statistically significant (p < 0.05) change in function from pre to post treatment in the placebo group. Data are presented as mean (1SD).

Figure 3

Pain levels pre and post treatment. This figure shows the pain levels, as measured by a 0-100 mm Visual Analogue Scale (VAS) pre and post treatment for both groups. * indicates a statistically significant (p < 0.05) change in pain from pre to post treatment in the placebo group. Data are presented as mean (1SD).

Figure 4

Change in pain and function pre to post treatment. This figure shows the change in pain and function levels from pre to post treatment, as measured by the 0-100 mm pain Visual Analogue Scale (VAS) and Roland Morris Disability Questionnaire (RMDQ) respectively. Data are presented as mean (1SD).