Transcutaneous electrical nerve stimulation and heat to reduce pain in a chronic low back pain population: a randomized controlled clinical trial

•The combination of heat and TENS significantly improves pain pressure thresholds.•The combination of heat and TENS does not affect maximum and average pain, nor movement-evoked pain (MEP).•There is a need for standardized and sensitive assessment tools for measuring MEP. Low back pain is the leading cause of disability worldwide. The therapeutic management of patients with chronic LBP is challenging. The aim of this study is to evaluate the effects of heat and transcutaneous electrical nerve stimulation combined on pain relief in participants with chronic low back pain. Fifty participants with chronic (≥3 months) low back pain were randomly assigned to two groups: HeatTens (n=25) and control group (n=25). Primary outcome was pain. Secondary outcomes were pressure pain thresholds, temporal summation, conditioned pain modulation, fear-avoidance and beliefs questionnaire, central sensitization inventory, quality of life, and medication use. The control group received no treatment and continued usual care. After four weeks of treatment, all measurements were repeated. Fifty individuals participated in this study. Significant higher pressure pain threshold measures after both 30min and 4 weeks for the lower back region and the second plantar toe were found only in the experimental group. The combination of heat and transcutaneous electrical nerve stimulation does not reduce pain scores in patients with chronic low back pain. Pressure pain threshold values significantly improved, showing beneficial effects of the experimental treatment. ClinicalTrials.gov: NCT03643731 (https://clinicaltrials.gov/ct2/show/NCT03643731).