The effect of spinal manipulation on brain neurometabolites in chronic nonspecific low back pain patients: a randomized clinical trial

Background In patients with chronic nonspecific low back pain (NCLBP), brain function changes due to the neuroplastic changes in different regions. Aim The current study aimed to evaluate the brain metabolite changes after spinal manipulation, using proton magnetic resonance spectroscopy (H-1-MRS). Methods In the current study, 25 patients with NCLBP aged 20-50 years were enrolled. Patients were randomly assigned to lumbopelvic manipulation or sham. Patients were evaluated before and 5 weeks after treatment by the Numerical Rating Scale (NRS), the Oswestry Disability Index (ODI), and H-1-MRS. Results After treatment, severity of pain and functional disability were significantly reduced in the treatment group vs. sham group (p < 0.05). After treatment, N-acetyl aspartate (NAA) in thalamus, insula, dorsolateral prefrontal cortex (DLPFC) regions, as well as choline (Cho) in the thalamus, insula, and somatosensory cortex (SSC) regions, had increased significantly in the treatment group compared with the sham group (p < 0.05). A significant increase was further observed in NAA in thalamus, anterior cingulate cortex (ACC), and SCC regions along with Cho metabolite in thalamus and SCC regions after treatment in the treatment group compared with the baseline measures (p < 0.05). Also, a significant increase was observed in Glx (glutamate and glutamine) levels of thalamus (p = 0.03). There was no significant difference in terms of brain metabolites at baseline and after treatment in the sham group. Conclusion In the patient with low back pain, spinal manipulation affects the central nervous system and changes the brain metabolites. Consequently, pain and functional disability are reduced.