Effects of noxious thermal stimulation on lower-limb motor function in chronic stroke: a randomized controlled trial with 1-month follow-up.

In 30 seconds

This assessor-blind randomized controlled trial evaluated three weeks of noxious thermal stimulation alongside usual rehabilitation in 37 people more than six months after a first-ever stroke. Participants received cold-only, heat-only, or alternating heat and cold stimulation; lower-limb function was assessed after treatment and at one month. The group-by-time effect was significant only for Timed Up and Go (TUG) performance (p = .041, ηp² = 0.16). The cold-only group had significantly shorter TUG times than at baseline at both post-intervention and follow-up, while other measured outcomes did not significantly change.

Key findings

• The group-by-time interaction was significant for TUG only (p = .041, ηp² = 0.16).
• In the cold-only group, TUG times were significantly shorter than baseline after treatment and at follow-up (p = .036 and <0.001, respectively).
• Alternating stimulation showed within-group TUG improvement, but post-hoc pairwise comparisons were not significant after correction (p > .05).
• No significant changes occurred in FMA-LE, Barthel index, or Hmax/Mmax ratio (p > .05).

Why it matters

Lower-limb mobility is a relevant rehabilitation outcome after stroke. These findings suggest that noxious cold stimulation, when added to regular rehabilitation, may improve TUG performance in chronic stroke, with differences from baseline still evident at one month. The absence of significant changes in other measured outcomes indicates that the observed signal was specific to mobility as assessed by TUG.

What to keep in mind

The trial included 37 participants across three groups, and follow-up extended only one month after the intervention. The reported significant benefit was limited to TUG; other measured outcomes did not change significantly.