Background: Chronic low back pain (CLBP) affects 80.0% of the population and reduces their quality of life (QOL). Searching for its most effective treatment has being a challenge in the health-care system. Although studies using transcranial direct current stimulation (tDCS) plus physical therapy (PT) that aim to relieve pain, an optimal intervention method and clinical effectiveness evaluations related to CLBP patient aspects have not been completely investigated.

Objectives: The purpose of this study was to compare treatment effects between a combination of tDCS and PT (combined group) and PT alone (PT group) in pain intensity, gait speed, lumbar range of motion (LROM), QOL in CLBP patients. Besides, we examined the relationships between pain intensity and the remaining variables.

Methods: Twenty CLBP patients participated in this study, randomly divided into PT group and combined group following a 1:1 ratio. Pain intensity, gait speed, LROM, QOL were evaluated before (Pre) and after treatment (Post) as well as a follow-up after 1 week (W1), 2 weeks (W2), 3 weeks (W3), and 4 weeks (W4).

Results: The results showed a significant improvement in pain intensity, gait speed, LROM, QOL in 2 groups, but there were no statistically significant differences between groups for pain intensity, fast speed, lumbar bending the left (LBL), lumbar bending the right (LBR), and QOL. Furthermore, the combined group indicated a correlation: the larger the pain reduction, the larger the gait speed improvement.

Conclusion: A combination between tDCS and PT may be a potentially physiologic method to promote therapeutic efficacy and improve gait speed for CLBP patients.