[Correlation between neck pressure pain threshold and forward head posture in patients with temporomandibular joint disorders].

Objective: To investigate the association between neck muscles pressure pain thresholds (PPT) and forward head posture (FHP) in patients with temporomandibular disorders (TMD). Methods: A total of 145 TMD patients, including 23 males and 122 females with a median age of 28 years, were enrolled in the Department of Rehabilitation Medicine, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine from December 2019 to April 2020. Informations of FHP and neck muscles PPT were collected for all participants. FHP was characterized by the craniocervical angle (CVA) between C7, the tragus of the ear and the horizontal line. Each of the participants completed a questionaire of the neck disability index (NDI). The patients with CVA≤51 ° were asigned into FHP group, otherwise the patients with CVA>51° were asigned into non-FHP group. PPT were measured at the midpoint of the upper trapezius and 1 cm aside from C5-C6 articular pillars. Nonparametric test and Spearman correlation analysis were conducted for the data analysis. Results: There were 70 patients in the FHP group and 75 patients in the non-FHP group. The trapezius PPT of the FHP group [2.82(0.86) kg] was significantly higher than that of the non-FHP group [2.46(0.80) kg] (P<0.01). No significant differences in PPT and NDI were observed between the two groups (P>0.05). Low correlation was found between trapezius PPT and FHP negatively (r=-0.273, P<0.01) and no correlation was found between C5-C6 PPT and FHP (r=-0.124, P>0.05). PPT in trapezius and C5-C6 was negatively correlated with NDI in moderate (r=-0.301, P<0.01) and low (r=-0.206, P<0.05) levels. Conclusions: The trapezius PPT was correlated with FHP negatively. The more FHP, the more pain tolerant of trapezius muscles. There was no correlation between neck function and FHP directly. The higher threshold was followed by better neck function.目的： 探索颞下颌关节紊乱病（temporomandibular disorders，TMD）患者颈部肌肉压力疼痛阈值（pressure pain threshold，PPT）与头前伸姿势及颈部功能之间的关系。 方法： 纳入2019年12月至2020年4月就诊于上海交通大学医学院附属第九人民医院康复科的145例TMD患者，其中男性23例，女性122例，年龄为28（9）岁。评估所有患者的头前伸角度、颈部特定肌肉PPT。通过照片拍摄法测量耳屏与C7棘突的连线和水平线之间的夹角为头前伸角度（头颈角），头颈角≤51°为头前伸组，头颈角>51°为非头前伸组。PPT的测定点为上束斜方肌的中点及C5-C6棘突旁1 cm。患者填写颈椎功能障碍指数量表（neck disability index，NDI）。两组患者的年龄符合正态分布但方差不齐，采用独立t′检验；两组患者的PPT、NDI和头颈角数据均不符合正态分布，用中位数（四分位数间距）表示，采用Mann-Whitney U检验及Spearman相关分析。 结果： 头前伸组患者70例，非前伸组患者75例。头前伸组患者的斜方肌PPT［2.82（0.86） kg］显著大于非前伸组［2.46（0.80） kg］（P<0.01）。两组患者的C5-C6棘突旁PPT及NDI差异均无统计学意义（P>0.05）。头颈角与斜方肌PPT呈低度负相关（r=-0.273，P<0.01），与C5-C6处PPT不相关（r=-0.124，P>0.05）；NDI与斜方肌PPT呈中度负相关（r=-0.301，P<0.01），与C5-C6处PPT呈低度负相关（r=-0.206，P<0.05）。 结论： TMD患者仅颈部斜方肌PPT与头前伸姿势呈低度负相关，患者头愈前伸反而颈部肌肉抗压痛能力愈强。颈部功能与头前伸角度不相关，但与肌肉压痛阈值密切相关，阈值愈高颈部功能愈好。.