Department of Anesthesia and Pain Medicine, Nishinomiya Municipal Central Hospital, Nishinomiya, Japan.
J Anesth. 2011 Aug;25(4):523-30. doi: 10.1007/s00540-011-1173-9. Epub 2011 Jun 2.
The purpose of this study was to elucidate the central processing of painful mechanical stimulation to muscle and bone by measuring blood oxygen level-dependent signal changes using functional magnetic resonance imaging (fMRI).
Twelve healthy volunteers were enrolled. Mechanical pressure on muscle and bone were applied at the right lower leg by an algometer. Intensities were adjusted to cause weak and strong pain sensation at either target site in preliminary testing. Brain activation in response to mechanical nociceptive stimulation targeting muscle and bone were measured by fMRI and analyzed.
Painful mechanical stimulation targeting muscle and bone activated the common areas including bilateral insula, anterior cingulate cortex, posterior cingulate cortex, secondary somatosensory cortex (S2), inferior parietal lobe, and basal ganglia. The contralateral S2 was more activated by strong stimulation than by weak stimulation. Some areas in the basal ganglia (bilateral putamen and caudate nucleus) were more activated by muscle stimulation than by bone stimulation.
The putamen and caudate nucleus may have a more significant role in brain processing of muscle pain compared with bone pain.
本研究旨在通过功能性磁共振成像（fMRI）测量血氧水平依赖信号变化，阐明肌肉和骨骼的疼痛机械刺激的中枢处理。
纳入 12 名健康志愿者。通过压力计在右小腿上对肌肉和骨骼施加机械压力。在初步测试中，将强度调整为在两个目标部位引起弱和强疼痛感觉。通过 fMRI 测量并分析针对肌肉和骨骼的机械伤害性刺激引起的大脑激活。
针对肌肉和骨骼的疼痛机械刺激激活了包括双侧脑岛、前扣带回皮质、后扣带回皮质、次级体感皮层（S2）、下顶叶和基底节在内的共同区域。强烈刺激比弱刺激更能激活对侧 S2。基底节的一些区域（双侧壳核和尾状核）对肌肉刺激的激活程度高于骨骼刺激。
与骨骼疼痛相比，壳核和尾状核在大脑处理肌肉疼痛方面可能具有更重要的作用。
