The aim of this investigation was to evaluate the effects of local anaesthesia on nerve growth factor (NGF) induced masseter hyperalgesia. Healthy participants randomly received an injection into the right masseter muscle of either isotonic saline (IS) given as a single injection (n = 15) or an injection of NGF (n = 30) followed by a second injection of lidocaine (NGF + lidocaine; n = 15) or IS (NGF + IS; n = 15) in the same muscle 48 h later. Mechanical sensitivity scores of the right and left masseter, referred sensations and jaw pain intensity and jaw function were assessed at baseline, 48 h after the first injection, 5 min after the second injection and 72 h after the first injection. NGF caused significant jaw pain evoked by chewing at 48 and 72 h after the first injection when compared to the IS group, but without significant differences between the NGF + lidocaine and NGF + IS groups. However, the mechanical sensitivity of the right masseter 5 min after the second injection in the NGF + lidocaine group was significantly lower than the second injection in the NGF + IS and was similar to the IS group. There were no significant differences for the referred sensations. Local anaesthetics may provide relevant information regarding the contribution of peripheral mechanisms in the maintenance of persistent musculoskeletal pain.

本研究的目的是评估局部麻醉对神经生长因子 (NGF) 诱导的咬肌痛觉过敏的影响。健康参与者随机向右侧咬肌注射等渗盐水 (IS)，单次注射 (n = 15) 或注射 NGF (n = 30)，然后第二次注射利多卡因 (NGF + 利多卡因； n = 15) 或 IS (NGF + IS; n = 15) 48 小时后在同一块肌肉中。在基线、第一次注射后 48 小时、第二次注射后 5 分钟和第一次注射后 72 小时评估左右咬肌的机械敏感性评分、牵涉感觉和下颌疼痛强度和下颌功能。与 IS 组相比，NGF 在第一次注射后 48 和 72 小时因咀嚼引起明显的下巴疼痛，但在 NGF + 利多卡因和 NGF + IS 组之间没有显着差异。然而，NGF + 利多卡因组第二次注射后 5 分钟右侧咬肌的机械敏感性显着低于 NGF + IS 组的第二次注射，并且与 IS 组相似。提到的感觉没有显着差异。局部麻醉剂可以提供有关外周机制在维持持续性肌肉骨骼疼痛中的作用的相关信息。