Department of Neurosurgery, Universitair Ziekenhuis Brussel, Brussels, Belgium; Pain in Motion International Research Group; and Department of Physiotherapy, Human Physiology and Anatomy, Faculty of Physical Education and Physiotherapy, Vrije Universiteit Brussel, Brussels, Belgium.
Department of Neurology, ZorgSaam Hospital, Terneuzen, the Netherlands, and Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel.
Phys Ther. 2019 Jul 1;99(7):915-923. doi: 10.1093/ptj/pzz051.
Descending nociceptive inhibitory pathways often malfunction in people with chronic pain. Conditioned pain modulation (CPM) is an experimental evaluation tool for assessing the functioning of these pathways. Spinal cord stimulation (SCS), a well-known treatment option for people with failed back surgery syndrome (FBSS), probably exerts its pain-relieving effect through a complex interplay of segmental and higher-order structures.
To the best of our knowledge, no clinical studies have thoroughly investigated the associations between SCS and CPM.
This was a prospective cohort study in people with FBSS.
Seventeen people who had FBSS and were scheduled for SCS were enrolled in this study. The CPM model was evaluated at both sural nerves and was induced by electrical stimulation as the test stimulus and the cold pressor test as the conditioning stimulus.
Before SCS, less than 30% of the participants with FBSS showed a CPM effect. Significant increases in the electrical detection threshold on the symptomatic side and the nonsymptomatic side were found. On the symptomatic side, no differences in the numbers of CPM responders before and after SCS could be found. On the nonsymptomatic side, more participants showed a CPM effect during SCS. Additionally, there were significant differences for CPM activation and SCS treatment.
Limitations were the small sample size and the subjective outcome parameters in the CPM model.
This study revealed a bilateral effect of SCS that suggests the involvement of higher-order structures, such as the periaqueductal gray matter and rostroventromedial medulla (key regions in the descending pathways), as previously suggested by animal research.
在慢性疼痛患者中，下行伤害性抑制通路经常出现功能障碍。条件性疼痛调制（CPM）是评估这些通路功能的实验评估工具。脊髓刺激（SCS）是一种治疗失败性背部手术综合征（FBSS）患者的知名方法，它可能通过节段和更高阶结构的复杂相互作用发挥其止痛作用。
据我们所知，没有临床研究彻底探讨 SCS 与 CPM 之间的关联。
这是一项针对 FBSS 患者的前瞻性队列研究。
这项研究纳入了 17 名计划接受 SCS 治疗的 FBSS 患者。在腓肠神经处评估 CPM 模型，并使用电刺激作为测试刺激，冷水压迫测试作为条件刺激来诱发 CPM。
在 SCS 之前，不到 30%的 FBSS 患者表现出 CPM 效应。在症状侧和非症状侧都发现了电检测阈值的显著增加。在症状侧，SCS 前后 CPM 反应者的数量没有差异。在非症状侧，更多的患者在 SCS 期间表现出 CPM 效应。此外，CPM 激活和 SCS 治疗之间存在显著差异。
局限性在于样本量小以及 CPM 模型中的主观结果参数。
这项研究揭示了 SCS 的双侧效应，表明涉及更高阶结构，如导水管周围灰质和吻侧腹内侧髓质（下行通路中的关键区域），正如之前的动物研究所表明的那样。
