Characteristics of Neuropathic Pain in Patients With Spinal Cord Injury

OBJECTIVE To characterize neuropathic pain in patients with spinal cord injury (SCI) according to classification used in the study by Baron et al. (Baron classification), a classification of neuropathic pain based on the mechanism. To also compare the patterns of neuropathic pain in SCI patients with those in patients with other etiologies and to determine the differences in patterns of neuropathic pain between the etiologies. METHODS This was a descriptive cross-sectional study. We used the Baron classification to investigate the characteristics of neuropathic pain in SCI. Sixty-one SCI patients with neuropathic pain (The Leeds assessment of neuropathic symptoms and signs score ≥12) were enrolled in this study between November 2012 and August 2013, after excluding patients <20 of age, patients with visual analog scale (VAS) score <3, pregnant patients, and patients with systemic disease or pain other than neuropathic pain. RESULTS The most common pain characteristic was pricking pain followed by electrical pain and numbness. The mean VAS score of at-level neuropathic pain was 7.51 and that of below-level neuropathic pain was 6.83. All of the patients suffered from rest pain, but 18 (54.6%) patients with at-level neuropathic pain and 20 (50.0%) patients with below-level neuropathic pain suffered from evoked pain. There was no significant difference in between at-level and below-level neuropathic pains. CONCLUSION The result was quite different from the characteristics of post-herpetic neuralgia, but it was similar to the characteristics of diabetic neuropathy as shown in the study by Baron et al., which means that sensory nerve deafferentation may be the most common pathophysiologic mechanism of neuropathic pain after SCI. Since in our study, we included short and discrete symptoms and signs based on diverse mechanisms, our results could be helpful for determining further evaluation and treatment.