Study Summary

Twenty-nine patients with chronic low back pain were randomized to receive either standard physiotherapy including transcutaneous electrical nerve stimulation (TENS) or the same program with intramuscular electrical stimulation (IMES) replacing TENS. The primary outcomes of interest were multifidus muscle properties including muscle stiffness, muscle tension, and tissue perfusion. Secondary outcomes of interest included pressure pain threshold (PPT), pain intensity, range of motion (ROM), postural stability, and maximal voluntary contraction. Outcomes were assessed at baseline, immediately after a 6 week intervention, and at a 4 week follow-up post intervention. Overall, the results of the study revealed statistically significant improvements in muscle tension, tissue perfusion, PPT, pain intensity, ROM, and postural stability favouring the IMES group, while no significant differences were observed for muscle stiffness or maximal voluntary contraction. These findings suggest that IMES may enhance neuromuscular function and pain modulation when incorporated into multimodal rehabilitation for chronic low back pain.