Association of Upper Trapezius Muscle Status With Pain and Disability in Patients With Chronic Nonspecific Neck Pain: A Cross‐Sectional Study
Jialin Yang, Hanyu Zou, Fangfang Xie, Chong Guan, Jianwen Ma, Juntao Chen, Fei YaoBackground
Chronic nonspecific neck pain (CNSNP) is a leading cause of disability worldwide. Alterations in upper trapezius tissue hardness and pain sensitivity may be closely associated with pain intensity and disability. This study aimed to investigate the associations of upper trapezius tissue hardness and pressure pain threshold (PPT) with pain intensity and neck disability in patients with CNSNP.
Methods
This single‐center cross‐sectional study enrolled 426 patients with CNSNP (244 women and 182 men; mean age, 44.22 ± 8.84 years) at the Health Examination Center of Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine between August 2024 and August 2025. Bilateral upper trapezius tissue hardness and PPT were measured using the OE220 outcome evaluation system (ITO, Japan). Pain intensity was assessed with a composite visual analog scale (VAS) score, and neck disability with the neck disability index (NDI). Spearman correlation analysis and linear regression models were used to evaluate the associations among variables, followed by prespecified subgroup analyses to explore the heterogeneity of these associations across demographic and clinical subgroups.
Results
Spearman correlation analysis showed that mean hardness was positively correlated with VAS ( r = 0.328, p < 0.001) and NDI ( r = 0.173, p < 0.001), whereas mean PPT was negatively correlated with VAS ( r = −0.307, p < 0.001) and NDI ( r = −0.121, p < 0.05). Multiple linear regression analysis showed that, after full adjustment for confounding factors, mean hardness remained positively associated with VAS ( B = 0.071, β = 0.268, 95% CI: 0.051∼0.091, p < 0.001), while mean PPT was negatively associated with VAS ( B = −0.187, β = −0.113, 95% CI: −0.316∼−0.058, p = 0.005); the adjusted model explained 40.8% of the variance. Regarding the NDI, only mean hardness was significantly and positively associated with it ( B = 0.180, β = 0.160, 95% CI: 0.075∼0.286, p < 0.001). In prespecified subgroup analyses, formal interaction tests showed no statistically significant effect modification for either outcome (all p for interaction > 0.05); the smallest p value, for the hardness‐by‐work‐type interaction on the NDI, was 0.122, and this exploratory observation was not regarded as evidence of effect modification.
Conclusion
In patients with CNSNP, increased tissue hardness and elevated local pain sensitivity of the upper trapezius are closely associated with pain intensity, and tissue hardness is a relevant factor associated with cervical dysfunction. These findings suggest that objective upper trapezius muscle status indicators may provide complementary descriptive information in the assessment of CNSNP, although their incremental clinical value beyond conventional assessment has not been established; longitudinal studies are needed to determine whether these indicators can guide treatment or predict outcomes.