Burns E, Chipchase L S, Schabrun S M
Brain Rehabilitation and Neuroplasticity Unit, School of Science and Health, Western Sydney University, Australia.
Eur J Pain. 2016 Sep;20(8):1203-13. doi: 10.1002/ejp.859. Epub 2016 Feb 23.
Acute muscle pain has both motor and sensory consequences, yet the effect of muscle pain on the primary sensory (S1) and motor (M1) cortices has yet to be systematically evaluated. Here we aimed to determine the strength of the evidence for (1) altered activation of S1/M1 during and after pain, (2) the temporal profile of any change in activation and (3) the relationship between S1/M1 activity and the symptoms of pain. In September 2015, five electronic databases were systematically searched for neuroimaging and electrophysiological studies investigating the effect of acute experimental muscle pain on S1/M1 in healthy volunteers. Demographic data, methodological characteristics and primary outcomes for each study were extracted for critical appraisal. Meta-analyses were performed where appropriate. Twenty-five studies satisfied the inclusion criteria. There was consistent evidence from fMRI for increased S1 activation in the contralateral hemisphere during pain, but insufficient evidence to determine the effect at M1. Meta-analyses of TMS and EEG data revealed moderate to strong evidence of reduced S1 and corticomotor excitability during and following the resolution of muscle pain. A comprehensive understanding of the temporal profile of altered activity in S1/M1, and the relationship to symptoms of pain, is hampered by differences in methodological design, pain modality and pain severity between studies. Overall, the findings of this review indicate reduced S1 and corticomotor activity during and after resolution of acute muscle pain, mechanisms that could plausibly underpin altered sensorimotor function in pain. WHAT DOES THIS REVIEW ADD?: We provide the first systematic evaluation of the primary sensory (S1) and motor (M1) cortex response to acute experimental muscle pain in healthy volunteers. We present evidence from a range of methodologies to provide a comprehensive understanding of the effect of pain on S1/M1. Through meta-analyses we evaluate the strength of evidence concerning the direction and temporal profile of the S1/M1 response to acute muscle pain.
急性肌肉疼痛会产生运动和感觉方面的后果，然而肌肉疼痛对初级感觉皮层（S1）和运动皮层（M1）的影响尚未得到系统评估。在此，我们旨在确定以下方面证据的强度：（1）疼痛期间及之后S1/M1激活的改变；（2）激活变化的时间特征；（3）S1/M1活动与疼痛症状之间的关系。2015年9月，我们系统检索了五个电子数据库，以查找有关急性实验性肌肉疼痛对健康志愿者S1/M1影响的神经影像学和电生理学研究。提取了每项研究的人口统计学数据、方法学特征和主要结果，以进行严格评估。在适当的情况下进行荟萃分析。25项研究符合纳入标准。功能磁共振成像（fMRI）有一致证据表明，疼痛期间对侧半球的S1激活增加，但没有足够证据确定对M1的影响。经颅磁刺激（TMS）和脑电图（EEG）数据的荟萃分析显示，有中度到有力的证据表明，在肌肉疼痛缓解期间及之后，S1和皮质运动兴奋性降低。由于研究之间在方法设计、疼痛模式和疼痛严重程度方面存在差异，因此对S1/M1活动改变的时间特征以及与疼痛症状的关系缺乏全面了解。总体而言，本综述的结果表明，在急性肌肉疼痛缓解期间及之后，S1和皮质运动活动降低，这些机制可能是疼痛中感觉运动功能改变的合理基础。本综述补充了什么内容？：我们首次对健康志愿者中初级感觉皮层（S1）和运动皮层（M1）对急性实验性肌肉疼痛的反应进行了系统评估。我们展示了来自一系列方法的证据，以全面了解疼痛对S1/M1的影响。通过荟萃分析，我们评估了有关S1/M1对急性肌肉疼痛反应的方向和时间特征的证据强度。
