Qanbari Soheila, Khanmohammadi Roya, Olyaei Gholamreza, Hosseini Zohreh, Hejazi Hanie Sadat
Physical Therapy Department, Tehran University of Medical Sciences, Tehran, Iran.
PLoS One. 2024 Dec 19;19(12):e0314361. doi: 10.1371/journal.pone.0314361. eCollection 2024.
Chronic low back pain (CLBP) is linked to reduced excitability in the primary motor (M1) and sensory (S1) cortices. Combining sensory-motor exercises with transcranial direct current stimulation (tDCS) to boost M1 and S1 excitability may improve treatment outcomes. This combined approach aligns with the neurophysiological mechanisms underlying CLBP and may target the neuroplastic changes induced by low back pain. This study aimed to assess whether enhancing M1 and S1 excitability via tDCS, alongside sensory-motor exercises, offers additional benefits for CLBP patients.
Participants were randomly assigned to receive either real or sham tDCS alongside sensory-motor exercises. Outcome measures included pain intensity, disability level, motor control ability, amplitudes of N80 and N150, and the amplitude of motor-evoked potential (MEP) and active motor threshold (AMT) for the multifidus (MF) and transversus abdominis/internal oblique (TrA/IO) muscles. A linear mixed-effects model (LMM) analyzed group, time, and interaction effects, while Spearman's correlation assessed relationships between neurophysiological and clinical outcomes.
The results showed significant reductions in pain intensity and disability levels (P < 0.001) and improved motor control (P < 0.001) in both groups. Both groups also exhibited increase in MF MEP amplitude (P = 0.042) and N150 amplitude (P = 0.028). The tDCS group demonstrated a significant decrease in AMT of MF and TrA/IO muscles (P < 0.05) and an increase in N80 amplitude (P = 0.027), with no significant changes in the control group. Additionally, the tDCS group had significantly lower AMT for the TrA/IO muscle in the post-test compared to the sham group (P = 0.001). Increased N150 amplitude was correlated with improved motor control.
The findings showed that sensory-motor exercises combined with either tDCS or sham tDCS effectively reduced pain intensity, decreased disability, and improved lumbar motor control in lumbosacral radiculopathy patients. No significant differences were observed between groups, indicating no added clinical benefit from tDCS over exercises alone. However, both groups demonstrated increased N150 and MF MEP amplitudes, suggesting enhanced cortical excitability in motor and sensory regions. While clinical outcomes were similar, neurophysiological data indicate that sensory-motor exercises play a central role in boosting cortical excitability, with tDCS further amplifying this effect, as evidenced by a significant AMT reduction in MF and TrA/IO muscles and an increase in N80 amplitude.
慢性下腰痛（CLBP）与初级运动皮层（M1）和感觉皮层（S1）兴奋性降低有关。将感觉运动锻炼与经颅直流电刺激（tDCS）相结合以提高M1和S1的兴奋性可能会改善治疗效果。这种联合方法符合CLBP潜在的神经生理机制，并且可能针对由下腰痛引起的神经可塑性变化。本研究旨在评估通过tDCS增强M1和S1兴奋性并结合感觉运动锻炼是否能为CLBP患者带来额外益处。
参与者被随机分配接受真实或假的tDCS并结合感觉运动锻炼。结果测量包括疼痛强度、残疾程度、运动控制能力、N80和N150的波幅，以及多裂肌（MF）和腹横肌/腹内斜肌（TrA/IO）的运动诱发电位（MEP）波幅和主动运动阈值（AMT）。线性混合效应模型（LMM）分析组间、时间和交互作用效应，而Spearman相关性评估神经生理和临床结果之间的关系。
结果显示两组的疼痛强度和残疾程度均显著降低（P < 0.001），运动控制能力得到改善（P < 0.001）。两组的MF MEP波幅（P = 0.042）和N150波幅（P = 0.028）也均有所增加。tDCS组的MF和TrA/IO肌肉的AMT显著降低（P < 0.05），N80波幅增加（P = 0.027），而对照组无显著变化。此外，与假刺激组相比，tDCS组在测试后TrA/IO肌肉的AMT显著更低（P = 0.001）。N150波幅增加与运动控制改善相关。
研究结果表明，感觉运动锻炼联合tDCS或假tDCS均能有效降低腰骶神经根病患者的疼痛强度、减轻残疾程度并改善腰部运动控制。两组之间未观察到显著差异，表明tDCS相较于单纯锻炼并无额外的临床益处。然而，两组均显示N150和MF MEP波幅增加，表明运动和感觉区域的皮层兴奋性增强。虽然临床结果相似，但神经生理数据表明感觉运动锻炼在提高皮层兴奋性方面起核心作用，tDCS进一步放大了这种效应，如MF和TrA/IO肌肉的AMT显著降低以及N80波幅增加所证明。
