No abstract

Background: Motor cortex stimulation (MCS) has been used in the treatment of chronic neuropathic pain for more than 25 years. However, the mechanisms and outcome predictors still represent major challenges. Objectives: To investigate outcome predictors and potential mechanisms of MCS on central post-stroke pain (CPSP). Material and Methods: 16 CPSP patients were analyzed at our center. The pain intensity was assessed using a visual analog scale (VAS) before surgery and at the last follow-up. The Neuropathic Pain Symptom Inventory (NPSI) was used to assess pain intensity, analyze outcome predictors, and indicate potential mechanisms of MCS. Results: The mean VAS score before surgery (8.0 ± 0.7) was significantly higher than that of the last follow-up (5.3 ± 2.4, p < 0.001). Similarly, the mean total NPSI score before MCS (30.6 ± 12.2) was significantly reduced at the last follow-up (25.2 ± 15.1, p = 0.01). An analysis of the NPSI subscores revealed a significant association between burning pain relief and effective results (p = 0.041, Fisher’s exact test). Conclusions: Burning pain relief might predict long-term results for the therapeutic use of MCS in CPSP. The substantia gelatinosa may play an important role in the modulation of pain relief mediated by MCS.