Wright Anthony, Benson Heather A E, Will Rob, Moss Penny
*School of Physiotherapy and Exercise Science †School of Pharmacy, CHIRI Bioscience, Curtin University ‡School of Medicine and Pharmacology, University of Western Australia, Perth, WA.
Clin J Pain. 2017 Sep;33(9):793-803. doi: 10.1097/AJP.0000000000000458.
Cold hyperalgesia has been established as an important marker of pain severity in a number of conditions. This study aimed to establish the extent to which patients with knee osteoarthritis (OA) demonstrate widespread cold, heat, and pressure hyperalgesia. OA participants with widespread cold hyperalgesia were compared with the remaining OA cohort to determine whether they could be distinguished in terms of hyperalgesia, pain report, pain quality, and physical function.
A total of 80 participants with knee OA and 40 matched healthy, pain-free controls participated. OA participants completed a washout of their usual medication. Quantitative sensory testing was completed at 3 sites using standard methods. Cold pain threshold (CPT) and heat pain thresholds (HPT) were tested using a Peltier thermode and pressure pain thresholds (PPT) using a digital algometer. All participants completed the short-form health survey questionnaire and OA participants completed the PainDETECT, Western Ontario and McMaster Universities Osteoarthritis Index of the Knee (WOMAC), and pain quality assessment scale questionnaires.
OA participants demonstrated widespread cold hyperalgesia (P<0.0001), had lower PPT at the index knee (P<0.0001) compared with controls and reported decreased physical health on the SF-36 (P=0.01). The OA subcohort with high global CPT (≥12.25°C) exhibited multimodality sensitization compared with the remaining OA cohort (PPT P<0.0001; CPT P<0.0001; HPT P=0.021 index knee). This group also reported increased pain, decreased function, and more features of neuropathic pain.
This study identified a specific subgroup of patients with knee OA who exhibited widespread, multimodality hyperalgesia, more pain, more features of neuropathic pain, and greater functional impairment. Identification of patients with this pain phenotype may permit more targeted and effective pain management.
在多种病症中，冷痛觉过敏已被确立为疼痛严重程度的重要标志。本研究旨在确定膝骨关节炎（OA）患者出现广泛冷、热和压力痛觉过敏的程度。将有广泛冷痛觉过敏的OA参与者与其余OA队列进行比较，以确定能否在痛觉过敏、疼痛报告、疼痛性质和身体功能方面对他们加以区分。
共有80名膝OA参与者和40名匹配的健康、无疼痛对照者参与。OA参与者停用了他们常用的药物。使用标准方法在3个部位完成定量感觉测试。使用珀耳帖热刺激器测试冷痛阈值（CPT）和热痛阈值（HPT），使用数字式痛觉计测试压力痛阈值（PPT）。所有参与者均完成了简明健康调查问卷，OA参与者还完成了疼痛检测问卷、西安大略和麦克马斯特大学膝骨关节炎指数（WOMAC）以及疼痛性质评估量表问卷。
OA参与者表现出广泛的冷痛觉过敏（P<0.0001），与对照组相比，患侧膝关节的PPT较低（P<0.0001），并且在SF-36健康调查中报告身体健康状况下降（P=0.01）。与其余OA队列相比，全球CPT高（≥12.25°C）的OA亚组表现出多模式敏化（PPT P<0.0001；CPT P<0.0001；患侧膝关节HPT P=0.021）。该组还报告疼痛加剧、功能下降以及更多神经性疼痛特征。
本研究确定了膝OA患者中的一个特定亚组，他们表现出广泛的多模式痛觉过敏、更多疼痛、更多神经性疼痛特征以及更严重的功能障碍。识别具有这种疼痛表型的患者可能有助于进行更有针对性和有效的疼痛管理。
