Linde Lukas D, Duarte Felipe Ck, Esmaeili Hamid, Hamad Abdul, Masani Kei, Kumbhare Dinesh A
ICORD, University of British Columbia, Vancouver, British Columbia, Canada.
School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada.
Br J Pain. 2021 Feb;15(1):102-113. doi: 10.1177/2049463720913289. Epub 2020 Apr 22.
The nociceptive flexion reflex (NFR) is used in neurophysiological research as an objective measure of nociception. NFR thresholds are reduced in numerous chronic pain pathologies, which are indicative of common central hyperexcitability within conditions. However, variation exists in both the NFR assessment and determinants of NFR threshold among research groups. Our purpose was to provide a review of the recent literature to (a) confirm the NFR threshold's efficacy in identifying those with chronic pain compared to controls and (b) provide a narrative synthesis on the current methodology used to assess the NFR in clinical populations. We conducted a review of multiple databases (MEDLINE, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Google Scholar and Cochrane Library), including articles that reported controlled clinical studies of humans, in English, comparing NFR thresholds within chronic pain conditions to matched control subjects, published since the last NFR review in 2010. Our search resulted in nine studies included in our narrative synthesis and eight studies included in a meta-analysis. There was a significant pooled standardized mean difference in NFR threshold between chronic pain conditions and controls (-0.94, 95% confidence interval (CI) -1.33 to -0.55, < 0.0001), with substantial heterogeneity of pooled estimates ( = 87%, = 0.41, = 76.13, the degrees of freedom (df) = 11, < 0.0001). Significant variations in participant positioning, stimulation parameters and determinants of the NFR threshold were evident among included studies. We provided a narrative synthesis on the methodologies of included studies, as a recommendation for future studies in the assessment of the NFR in chronic pain.
伤害性屈曲反射（NFR）在神经生理学研究中被用作伤害感受的客观指标。在许多慢性疼痛病症中，NFR阈值会降低，这表明在这些病症中存在共同的中枢性兴奋性过高。然而，不同研究组在NFR评估和NFR阈值的决定因素方面存在差异。我们的目的是对近期文献进行综述，以（a）确认与对照组相比，NFR阈值在识别慢性疼痛患者方面的有效性，以及（b）对目前用于评估临床人群NFR的方法进行叙述性综合分析。我们对多个数据库（MEDLINE、护理及相关健康文献累积索引（CINAHL）、谷歌学术和考克兰图书馆）进行了综述，纳入了自2010年上次NFR综述以来发表的、以英文报道的关于人类对照临床研究的文章，这些研究比较了慢性疼痛病症患者与匹配对照组的NFR阈值。我们的检索结果是，有9项研究纳入了我们的叙述性综合分析，8项研究纳入了荟萃分析。慢性疼痛病症组与对照组之间的NFR阈值合并标准化均数差异显著（-0.94，95%置信区间（CI）-1.33至-0.55，P＜0.0001），合并估计值存在显著异质性（I² = 87%，P = 0.41，Q = 76.13，自由度（df）= 11，P＜0.0001）。纳入研究中，参与者体位、刺激参数和NFR阈值的决定因素存在显著差异。我们对纳入研究的方法进行了叙述性综合分析，作为对未来慢性疼痛NFR评估研究的建议。
