Department of Biomedical Engineering, Kyung Hee University, Yongin, Republic of Korea.
Center for Neuroscience Imaging Research, Institute for Basic Science, Suwon, Republic of Korea.
PLoS One. 2020 Jun 1;15(6):e0233858. doi: 10.1371/journal.pone.0233858. eCollection 2020.
Low back pain (LBP) is a common ailment in most developed countries. Because most cases of LBP are known as 'non-specific', it has been challenging to develop experimental pain models of LBP which reproduce patients' clinical pain. In addition, previous models have limited applicability in a steady-pain-state neuroimaging environment. Thus, this study aims to devise a low back pain model with a simple methodology to induce experimental LBP, which has similar pain properties to patients' clinical pain, and to apply the model in a steady-pain-state neuroimaging study.
Our low back extension (LBE) pain model was tested on 217 LBP patients outside the magnetic resonance imaging (MRI) scanner to determine the reproducibility of endogenous pain and the similarity to their own clinical pain (STUDY1), and applied in a steady-pain-state functional MRI study (47 LBP patients and 23 healthy controls) to determine its applicability (induced head motions and brain functional connectivity changes; STUDY2).
By the LBE pain model, 68.2% of the LBP patients reported increased LBP with high similarity of sensations to their own clinical pain (STUDY1), and the head motions were statistically similar to and correlated with those in resting state (STUDY2). Furthermore, the LBE model altered brain functional connectivity by decreasing the default-mode and the sensorimotor networks, and increasing the salience network, which was significantly associated with the intensity of the induced pain. Conversely, the healthy controls showed increased somatosensory network (but not of the cognitive pain processing).
Our investigations suggest that our LBE pain model, which increased LBP with high similarity to the LBP patients' own pain sensation and induced patient-specific brain responses with acceptable head motion, could be applied to neuroimaging studies investigating brain responses to different levels of endogenous LBP.
腰痛（LBP）是大多数发达国家的常见疾病。由于大多数 LBP 病例被称为“非特异性”，因此很难开发出能够重现患者临床疼痛的 LBP 实验性疼痛模型。此外，以前的模型在稳定疼痛状态的神经影像学环境中的适用性有限。因此，本研究旨在设计一种腰痛模型，采用简单的方法诱导实验性 LBP，其疼痛特性与患者的临床疼痛相似，并将该模型应用于稳定疼痛状态的神经影像学研究。
我们的腰椎伸展（LBE）疼痛模型在磁共振成像（MRI）扫描仪外的 217 名 LBP 患者中进行了测试，以确定内源性疼痛的重现性及其与自身临床疼痛的相似性（研究 1），并应用于稳定疼痛状态的功能 MRI 研究（47 名 LBP 患者和 23 名健康对照者）以确定其适用性（诱导的头部运动和脑功能连接变化；研究 2）。
通过 LBE 疼痛模型，68.2%的 LBP 患者报告腰痛加重，且感觉与自身临床疼痛高度相似（研究 1），头部运动在统计学上与静息状态相似且相关（研究 2）。此外，LBE 模型通过降低默认模式和感觉运动网络，增加突显网络，改变了脑功能连接，这与诱导疼痛的强度显著相关。相反，健康对照组显示出感觉运动网络的增加（但不是认知疼痛处理）。
我们的研究表明，我们的 LBE 疼痛模型可以增加与 LBP 患者自身疼痛感觉高度相似的 LBP，并诱导具有可接受头部运动的患者特异性脑反应，可应用于研究不同水平内源性 LBP 对大脑反应的神经影像学研究。
