Center for Medical Genetics, Ghent University and Ghent University Hospital, Ghent, Belgium.
Department of Biomolecular Medicine, Ghent University, Ghent, Belgium.
Eur J Pain. 2022 Jul;26(6):1355-1367. doi: 10.1002/ejp.1956. Epub 2022 May 11.
The hypermobile type of Ehlers-Danlos syndrome (hEDS) is a heritable connective tissue disorder, associated with joint hypermobility and prominent chronic pain. Because experimental pain testing in hEDS is scarce, the underlying mechanisms are still poorly understood.
The present study assesses endogenous pain facilitation and pain inhibition in hEDS, using a protocol for temporal summation of pain (TSP), conditioned pain modulation (CPM) and exercise-induced hypoalgesia (EIH).
Twenty women with hEDS and 20 age-matched healthy controls participated. After evaluating thermal and mechanical pain thresholds (PPT), TSP was assessed using 10 repetitive painful pressure stimuli. CPM was provoked using pressure as the test stimulus and hand immersion in hot water (46°) as the conditioning stimulus. EIH was assessed after a submaximal cycling protocol.
The hEDS group demonstrated reduced PPTs and showed significantly more TSP after repeated painful stimuli than the control group. In comparison to the healthy control group, the hEDS group demonstrated significantly less EIH at the quadriceps test location. At the trapezius, EIH did not significantly differ between groups. No significant differences were found between the hEDS group and control group in the CPM response.
The results demonstrate increased TSP in hEDS, suggesting increased central pain facilitation. EIH should be studied more extensively but may be disturbed when evaluated in the muscles that are activated during exercise. The CPM results are inconclusive and require more research.
Studies regarding the mechanisms that underlie pain in hEDS are scarce, although it is the most prevalent and disabling symptom in this patient population. This study demonstrates increased temporal summation in hEDS and suggests that exercise-induced hypoalgesia may be reduced. Because exercise is a cornerstone in the multidisciplinary treatment of heritable connective tissue disorders, gaining knowledge in this field is important. Pressure stimuli were used to facilitate the international usability of the protocols, allowing for future data acquisition in large cohorts.
Ehlers-Danlos 综合征（hEDS）的高活动型是一种遗传性结缔组织疾病，与关节过度活动和明显的慢性疼痛有关。由于 hEDS 中的实验性疼痛测试很少，因此其潜在机制仍知之甚少。
本研究使用疼痛时间总和（TSP）、条件性疼痛调制（CPM）和运动诱导的镇痛（EIH）的方案评估 hEDS 中的内源性疼痛易化和疼痛抑制。
20 名 hEDS 女性和 20 名年龄匹配的健康对照者参与了研究。在评估热和机械疼痛阈值（PPT）后，使用 10 个重复的疼痛压力刺激来评估 TSP。CPM 通过使用压力作为测试刺激和将手浸入热水（46°C）中作为条件刺激来引发。在次最大循环方案后评估 EIH。
hEDS 组的 PPT 较低，与对照组相比，在重复疼痛刺激后表现出明显更多的 TSP。与健康对照组相比，hEDS 组在股四头肌测试部位的 EIH 明显减少。在斜方肌，EIH 组与对照组之间没有显著差异。hEDS 组和对照组在 CPM 反应之间没有显著差异。
结果表明 hEDS 中 TSP 增加，提示中枢疼痛易化增加。应该更广泛地研究 EIH，但在评估运动过程中激活的肌肉时，EIH 可能会受到干扰。CPM 结果不确定，需要更多的研究。
尽管 hEDS 是该患者群体中最常见和最致残的症状，但关于其疼痛机制的研究很少。本研究表明 hEDS 中 TSP 增加，并提示运动诱导的镇痛可能减少。由于运动是遗传性结缔组织疾病多学科治疗的基石，因此在该领域获得知识很重要。使用压力刺激来促进协议的国际可用性，允许在大样本中进行未来的数据采集。
