Aberrant alterations of static and dynamic functional connectivity in chronic low back pain

Chronic low back pain (CLBP) is a common disease with uncertain pathological mechanisms, resulting in significant social and economic burdens. Despite the identification of abnormal static functional connectivity (sFC) in brain regions related to pain through neuroimaging studies, the dynamic functional connectivity (dFC) in CLBP has not been thoroughly explored. In this study, 38 patients with CLBP and 38 gender- and age-matched healthy controls (HCs) were included. Resting-state functional magnetic resonance imaging (rs-fMRI) data were collected from both groups to compare the differences in sFC and dFC. Finally, we conducted partial correlation analyses between the sFC and dFC values of brain regions showing significant differences in the two groups and the clinical characteristics of patients with CLBP. Compared to HCs, patients with CLBP exhibited significantly decreased sFC and dFC in multiple brain regions including the caudate, dorsolateral superior frontal cortex, pallidum, hippocampus, thalamus, amygdala, supplementary motor area, lingual gyrus, and fusiform gyrus. Moreover, partial correlation analysis demonstrated a significant negative correlation between the dFC of the left hippocampus and left thalamus and VAS scores in patients with CLBP. The results indicate notable changes in both sFC and dFC among patients with CLBP, suggesting their involvement in the disturbance of pain processing, perception, and regulation. These findings offer novel insights into the underlying mechanisms of CLBP and could facilitate the development of more effective treatment approaches.