Efficacy of neuromodulation and rehabilitation approaches on pain relief in patients with spinal cord injury: a systematic review and meta-analysis

Introduction: Spinal cord injury (SCI) is a debilitating neurological condition that causes physical dependency, psychological distress, and financial burden. Pain is a common consequence of SCI, significantly impacting quality of life. Effective pain management in SCI is challenging and requires multifaceted approaches. Among rehabilitation methods, non-invasive brain stimulation techniques such as repetitive transcranial magnetic stimulation (rTMS), theta burst stimulation (TBS), transcranial direct current stimulation (tDCS), transcutaneous electrical nerve stimulation (TENS), and virtual reality (VR) have been explored. This study aims to evaluate the efficacy of rehabilitation and non-invasive brain stimulation techniques on pain relief in SCI patients. Methods: A systematic review of the literature was conducted using PubMed, Scopus, and ScienceDirect with the formula ("spinal cord injury") AND ("pain"). Risk of bias was assessed using the Cochrane Risk of Bias Tool. Results: Sixteen studies involving 319 patients were included. Patients in the control groups received: rTMS in seven trials, tDCS in seven trials, TBS in one trial, and TENS combined with VR in one trial. The trials analyzed were of poor methodological quality, characterized by small sample sizes, weak power analyses, varying clinical scores, and non-comparable follow-up periods. No major complications or serious adverse events were reported. Conclusion: Results were inconsistent, with no solid evidence supporting the superiority of rehabilitation techniques over comparator treatments. However, the favorable safety profile and positive outcomes in some measures suggest potential benefits for pain management and quality of life. Further studies are necessary to better understand SCI-related pain and optimize treatment strategies.