Brain metabolic alterations in individuals with chronic non-specific neck pain assessed using proton magnetic...

Altered brain metabolites in pain-related regions provide insights into the underlying mechanisms of chronic pain. However, brain metabolites alterations in chronic non-specific neck pain remain unknown. This study aimed to investigate brain metabolite concentrations in individuals with chronic non-specific neck pain and their relationships with pain-related outcomes. Participants included 30 individuals with chronic non-specific neck pain and 30 pain-free controls. Absolute concentrations and metabolite ratios of total creatine (tCr), choline (Cho), myo-inositol (mI), N-acetylaspartate (NAA) and glutamate/glutamine (Glx) were measured in regions involved in pain processing and modulation, including dorsolateral prefrontal cortex (DLPFC), primary somatosensory cortex (S1), insula and thalamus, using proton magnetic resonance spectroscopy (¹H-MRS). Compared to controls, participants with neck pain exhibited decreased mI and mI/tCr (left DLPFC and thalamus), NAA and NAA/tCr (right S1) and Glx and Glx/tCr (right DLPFC) and increased Cho and Cho/tCr (left S1) (adjusted p-values < 0.05). Altered metabolite levels were correlated with pain duration, intensity, extent, disability and PPT at C2-3 (r ranged from - 0.48 to 0.55, adjusted p-values < 0.05). The results suggest that ¹H-MRS detects altered levels of mI, NAA, Glx and Cho in specific brain regions involved in pain regulation, which may contribute to the persistence of neck pain.