Chronic low back pain is a leading health issue that leads to severe pain and disturbs brain functioning. Various therapeutic modalities like direct current stimulation (tDCS) and peripheral electrical stimulation (PES) proven to be very helpful in normalising brain functioning and alleviating pain. This study enlightened that the tDCS in combination with PES techniques can generate analgesic pain leading to pain alleviation.

Recent evidence suggests that chronic low back pain is associated with plastic changes in the brain that can be modified by neuromodulation strategies. This study investigated the efficacy of transcranial direct current stimulation (tDCS) combined simultaneously with peripheral electrical stimulation (PES) for pain relief, disability and global perception in patients with chronic low back pain (CLBP).

Ninety-two patients with CLBP were randomized to receive 12 sessions on nonconsecutive days of anodal tDCS (primary motor cortex, M1), 100 Hz sensory PES (lumbar spine), tDCS + PES or sham tDCS + PES. Pain intensity (11-point numerical rating scale), disability and global perception were applied before treatment and four weeks, three months and six months post-randomization.

A two points reduction was achieved only by the tDCS + PES (mean reduction [MR] = −2.6, CI95% = −4.4 to −0.9) and PES alone (MR = −2.2, CI95% = −3.9 to −0.4) compared with the sham group, but not of tDCS alone (MR = −1.7, CI95% = −3.4 to −0.0). In addition to maintaining the analgesic effect for up to three months, tDCS + PES had a higher proportion of respondents in different cutoff points. The global perception was improved at four weeks and maintained three months after treatment only with tDCS + PES. None of the treatments improved disability and the affective aspect of pain consistently with pain reduction.

The results suggest that tDCS + PES and PES alone are effective in relieving CLBP in the short term. However, only tDCS + PES induced a long-lasting analgesic effect. tDCS alone showed no clinically meaningful pain relief.