Department of Rehabilitation Sciences and Physiotherapy, Faculty of Medicine and Health Sciences, Ghent University.
Department of Rehabilitation Sciences and Physiotherapy, Ghent University, Belgium.
Pain Physician. 2017 Nov;20(7):E1025-E1051.
Patients with chronic whiplash-associated disorders (CWAD) are characterized by pain of traumatic origin, cognitive deficits, and central sensitization (CS). Previous neuroimaging studies revealed altered grey matter volume (GMV) in mild traumatic brain injury patients and chronic pain conditions also characterized by CS. It can therefore be hypothesized that GMV alterations also play a role in the persistent complaints of CWAD. However, brain alterations remain poorly investigated in these patients.
This study examined regional GMV alterations in patients with CWAD compared to patients with non-traumatic chronic idiopathic neck pain (CINP), who normally do not show CS at a group level, and healthy controls. Additionally, in both patient groups, relationships between regional GMV and measures of cognition as well as pain processing were assessed.
A cross-sectional case-control study.
This study was performed at the Department of Rehabilitation Sciences and Physiotherapy of Ghent University in cooperation with the Ghent Institute for Functional and Metabolic Imaging.
Ninety-three women (28 healthy controls, 34 CINP patients, and 31 CWAD patients) were enrolled. First, T1-weighted magnetic resonance images (MRIs) were acquired to examine GMV alterations in the brain regions involved in processing cognition and pain. Next, cognitive performance, pain cognitions, and CS symptoms were assessed. Finally, hyperalgesia and conditioned pain modulation efficacy were examined.
Regional GMV of the right lateral orbitofrontal cortex, left supramarginal cortex, and left posterior cingulate cortex was decreased in CWAD patients compared to healthy controls (P = 0.023; P = 0.012; P = 0.047, respectively). Additionally, GMV of the right superior parietal cortex and left posterior cingulate cortex was decreased in CWAD patients compared to CINP patients (P = 0.008; P = 0.035, respectively). Decreased regional GMV correlated with worse cognitive performance, higher maladapted pain cognitions, CS symptoms, and hyperalgesia in CWAD patients (rs = -0.515 to -0.657; P < 0.01). In CINP patients, decreased regional GMV correlated only with worse cognitive performance (rs = -0.499 to -0.619; P < 0.01), and no GMV differences compared with the controls could be revealed.
No conclusions about the causality of the observed relationships can be drawn.
These results provide the first evidence for reduced GMV in cortical regions involved in processing cognition and pain in patients with CWAD. Accordingly, it is recommended that therapy approaches for CWAD patients should address the brain and take into account neuroplasticity of the central nervous system (CNS).
Whiplash injuries, neck pain, magnetic resonance imaging, grey matter, cognitive dysfunction, pain catastrophizing, central sensitization.
慢性挥鞭样损伤相关障碍（CWAD）患者的特征为创伤性疼痛、认知缺陷和中枢敏化（CS）。先前的神经影像学研究表明，轻度创伤性脑损伤患者和同样表现出 CS 的慢性疼痛病症患者的灰质体积（GMV）发生了改变。因此，可以假设 GMV 的改变也在 CWAD 的持续症状中发挥作用。然而，这些患者的脑改变仍未得到充分研究。
本研究通过对比慢性特发性颈痛（CINP）患者（通常不会在组水平上表现出 CS）和健康对照组，来检测 CWAD 患者的脑灰质体积（GMV）改变。此外，在这两个患者组中，还评估了 GMV 与认知功能以及疼痛处理测量指标之间的关系。
这是一项横断面病例对照研究。
该研究在根特大学康复科学与物理治疗系与根特功能与代谢成像研究所合作进行。
纳入 93 名女性（28 名健康对照组、34 名 CINP 患者和 31 名 CWAD 患者）。首先，采集 T1 加权磁共振成像（MRI）来检测参与认知和疼痛处理的脑区的 GMV 改变。接下来，评估认知表现、疼痛认知和 CS 症状。最后，检测痛觉过敏和条件性疼痛调制的效果。
与健康对照组相比，CWAD 患者的右侧外侧眶额皮质、左侧缘上回和左侧后扣带回的 GMV 减少（P = 0.023；P = 0.012；P = 0.047）。此外，CWAD 患者的右侧顶上回和左侧后扣带回的 GMV 也比 CINP 患者减少（P = 0.008；P = 0.035）。CWAD 患者的 GMV 减少与认知表现更差、适应不良的疼痛认知、CS 症状和痛觉过敏相关（rs = -0.515 至 -0.657；P < 0.01）。CINP 患者的 GMV 减少仅与认知表现更差相关（rs = -0.499 至 -0.619；P < 0.01），且与对照组相比无 GMV 差异。
不能得出观察到的关系的因果关系的结论。
这些结果首次提供了 CWAD 患者参与认知和疼痛处理的皮质区域 GMV 减少的证据。因此，建议 CWAD 患者的治疗方法应针对大脑，并考虑中枢神经系统（CNS）的神经可塑性。
挥鞭样损伤、颈痛、磁共振成像、灰质、认知功能障碍、疼痛灾难化、中枢敏化。
