Instituto de Medicina Física e Reabilitação, Hospital das Clínicas HCFMUSP, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brasil.
Universidad San Ignacio de Loyola, Vicerrectorado de Investigación, Unidad de Investigación para la Generación y Síntesis de Evidencias en Salud, Lima, Peru; Neuromodulation Center and Center for Clinical Research Learning, Spaulding Rehabilitation, Hospital and Massachusetts General Hospital, Harvard Medical School, Boston, USA.
Neurophysiol Clin. 2022 Nov;52(6):413-426. doi: 10.1016/j.neucli.2022.09.006. Epub 2022 Nov 5.
The study aimed to examine the clinical and neurophysiological predictors of motor event-related desynchronization (ERD) and synchronization (ERS) in patients with chronic pain due to knee osteoarthritis (KOA).
We performed a cross-sectional analysis of our cohort study (DEFINE cohort), KOA arm, with 71 patients, including demographic, functionality, genetic and neurophysiological measures. ERD/ERS was evaluated during hand motor tasks (motor execution, active and passive observation, and imagery). Multivariate regression models were used to explore predictors of ERD/ERS.
Although we found an altered ERD/ERS pattern during motor execution and active observation, the ERS pattern could only be clearly differentiated after passive observation.`. We found no predictors of ERD (excitatory biomarker). For ERS (inhibitory biomarker), our results showed that the main predictors differ across EEG frequency bands. Considering pain measures, we found that visual analogue scale (VAS, right knee) and chronicity of pain negatively predict low beta and high beta ERS, respectively. Pain threshold was positively correlated with alpha ERS, while 36-Item Short Form Survey (SF-36) emotional domain positively predicted beta ERS. Regarding transcranial magnetic stimulation (TMS) markers, intracortical inhibition (ICF) negatively predicted beta and low beta ERS, and left hemisphere cortical silent period (CSP) negatively predicted low beta ERS.
Considering that higher power of ERS indicates a stronger cortical organization and inhibitory drive, our results show that limitation of activities due to emotional factors, lower pain threshold, higher VAS pain, and longer duration of pain are associated with lower ERS power (in alpha and beta frequencies), thus indicating a lower inhibitory drive. In the same direction, a lower inhibitory drive as indicated by higher ERS power is associated with higher ICF amplitude. Although there was a negative association between ERS and CSP, this may indicate that ICF values are adjusting CSP results. Our findings support the idea that a less organized cortical response as indicated by changes to the ERS is associated with higher pain correlates in subjects with KOA.
本研究旨在探讨膝骨关节炎（KOA）慢性疼痛患者运动事件相关去同步（ERD）和同步（ERS）的临床和神经生理预测因子。
我们对DEFINE 队列研究的 KOA 臂进行了横断面分析，共纳入 71 例患者，包括人口统计学、功能、遗传和神经生理学指标。在手部运动任务（运动执行、主动和被动观察、想象）期间评估 ERD/ERS。使用多元回归模型探索 ERD/ERS 的预测因子。
虽然我们发现运动执行和主动观察期间 ERD/ERS 模式发生改变，但仅在被动观察后才能清楚地区分 ERS 模式。我们未发现 ERD 的预测因子（兴奋生物标志物）。对于 ERS（抑制生物标志物），我们的结果表明，主要预测因子在不同的 EEG 频带中有所不同。考虑到疼痛指标，我们发现视觉模拟量表（VAS，右膝）和疼痛的慢性程度分别负相关于低β和高β ERS。疼痛阈值与α ERS 呈正相关，而 36 项简明健康调查（SF-36）情绪领域与β ERS 呈正相关。关于经颅磁刺激（TMS）标志物，皮质内抑制（ICF）负相关于β和低β ERS，左半球皮质静息期（CSP）负相关于低β ERS。
鉴于 ERS 的更高功率表明更强的皮质组织和抑制驱动，我们的结果表明，由于情绪因素导致的活动受限、较低的疼痛阈值、较高的 VAS 疼痛和较长的疼痛持续时间与较低的 ERS 功率（在α和β频率下）相关，从而表明较低的抑制驱动。在同一方向上，较高的 ERS 功率与较高的 ICF 幅度相关，表明较低的抑制驱动。尽管 ERS 与 CSP 之间存在负相关，但这可能表明 ICF 值正在调整 CSP 结果。我们的研究结果支持这样一种观点，即 KOA 患者的 ERS 变化表明皮质反应的组织性降低与更高的疼痛相关。
