Altered cortical morphology and structural covariance network in chronic neck and shoulder pain

Despite regional brain structural alterations reported in patients with chronic neck and shoulder pain (CNSP), the specific characteristics of surface-based morphometry (SBM) and structural covariance networks (SCNs) still remain unknown. This study applied cortical morphological and graph theoretical analysis to investigate cortical morphometric alterations and global and nodal network abnormalities in CNSP.

Fifty patients with CNSP and 50 matched healthy controls (HCs) were enrolled in this experiment. All participants underwent structural magnetic resonance imaging and clinical assessments. Cortical thickness (CT), sulcal depth (SD), cortical surface area (CSA), and cortical curvature (CC) of the two groups were calculated and compared. These metrics were then partial-correlated with clinical scales. Additionally, they were extracted from 68 brain regions according to the Desikan-Killiany atlas to construct SCNs for graph theoretical analysis, characterizing alterations in the topological properties in the patient group.

Compared with HCs, patients with CNSP exhibited widespread cortical alterations in morphological measures (CT, CSA, SD, and CC), predominantly involving frontal, parietal, and temporal subregions. Moreover, in the CNSP group, the SD of the right inferior parietal lobule was positively correlated with Pain Catastrophizing Scale (PCS) scores. Additionally, the patient group exhibited higher clustering coefficient and longer characteristic path length compared to HCs.

Our study demonstrated distinctive alterations of SBM and SCNs in patients with CNSP. These findings provide new insights into the cortical structural and network-level alterations associated with CNSP, contributing to a better understanding of its potential neurobiological basis.