The concept "nociplastic pain" has been developed for patients with features of nociceptive system sensitization that are not explained as nociceptive or neuropathic. Here, we tested how well the recently published grading system differentiates between chronic primary and secondary pain conditions. We recruited patients with fibromyalgia (FMS, n = 41), complex regional pain syndrome (CRPS, n = 11), osteoarthritis (OA, n = 21), or peripheral nerve injury (PNI, n = 8). We used clinical history, pain drawings, quantitative sensory testing (QST), and questionnaires to classify their pains as possibly or probably "nociplastic." All patients with chronic primary pain exhibited widespread/regional pain not explainable by either nociceptive or neuropathic mechanisms. Widespread pain occurred in 12 patients with OA but was identified as nociceptive in 11 of 12. Regional pain occurred in 4 patients with PNI but was identified as neuropathic in 3 of 4. At this step, the grading system had 100% sensitivity and 93% specificity. Clinical evidence for pain hypersensitivity by QST, and history of hypersensitivity and mental comorbidities did not differentiate between chronic primary pain (QST: 36/52 = 69%, history: 43/52 = 83%) and secondary pain conditions (QST: 20/29 = 69%, history: 24/29 83%). Based on these data, specificity remained excellent (93%), but sensitivity dropped substantially (60%) due to lacking evidence for pain hypersensitivity in many patients with FMS. This low sensitivity suggests that the published grading system is not suitable for screening purposes. We suggest structural and content modifications to improve sensitivity, including placement of patient history before clinical examination and addition of a high tender point count as evidence for widespread pain hypersensitivity.

中文翻译：

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“伤害性疼痛”分级系统在慢性原发性和慢性继发性疼痛病症中的应用：一项实地研究。


“伤害性疼痛”的概念是为具有伤害性感觉系统敏化特征的患者开发的，这些特征不被解释为伤害性或神经性。在这里，我们测试了最近发布的分级系统区分慢性原发性和继发性疼痛状况的能力。我们招募了纤维肌痛 （FMS， n = 41） 、复杂区域疼痛综合征 （CRPS， n = 11） 、骨关节炎 （OA， n = 21） 或周围神经损伤 （PNI， n = 8） 患者。我们使用临床病史、疼痛图、定量感官测试 （QST） 和问卷将他们的疼痛分类为可能或可能的 “伤害性增生”。所有慢性原发性疼痛患者都表现出无法用伤害感受或神经性机制解释的广泛/区域性疼痛。12 例 OA 患者发生广泛疼痛，但 12 例患者中有 11 例被确定为伤害性疼痛。4 例 PNI 患者发生局部疼痛，但 4 例患者中有 3 例被确定为神经性疼痛。在此步骤中，分级系统具有 100% 的敏感性和 93% 的特异性。QST 对疼痛过敏的临床证据以及超敏反应和精神合并症的病史不区分慢性原发性疼痛 （QST： 36/52 = 69%，病史： 43/52 = 83%） 和继发性疼痛状况 （QST： 20/29 = 69%，病史： 24/29 83%）。基于这些数据，特异性仍然非常好 （93%），但由于缺乏许多 FMS 患者疼痛超敏反应的证据，敏感性大幅下降 （60%）。这种低敏感性表明已发布的分级系统不适合用于筛选目的。 我们建议修改结构和内容以提高敏感性，包括在临床检查前放置患者病史，并增加高压痛点计数作为广泛性疼痛超敏反应的证据。