Orthopedics & Rheumatology

Biography

Biography: Kun Wang

Abstract

Purpose: The factors influencing the presence or absence of pain in sciatica secondary to disc herniation remain incompletely understood. We hypothesized that the imbalance in inflammatory cytokines is implicated in the generation of pain. In our study, serum levels of pro-inflammatory and anti-inflammatory cytokines were investigated among patients with severe sciatica; the serum levels were compared with those of patients with mild sciatica and healthy subjects. Methods: In this prospective study, blood protein levels of the pro-inflammatory cytokines, namely, interleukin-6(IL-6), interleukin-8 (IL-8),and tumor necrosis factor-α(TNF-α), and the anti-inflammatory cytokines, namely, interleukin-4 (IL-4) and interleukin-10 (IL-10), of 58 patients with severe sciatica, 50 patients with mild sciatica, and 30 healthy control subjects were analyzed through ELISA. Physical and mental health symptoms were determined using the Oswestry Disability Index (ODI) and Short Form-36 (SF-36) questionnaire. Spearman rank correlation coefficient was also determined to calculate the correlation between the scores obtained from the questionnaires and the serum levels of cytokines. Results: No significant difference in IL-6 levels was observed among the three groups; no significant difference in IL-8 levels was also found between severe sciatica and mild sciatica groups, although the IL-8 levels of the healthy controls were significantly different from those of the sciatica groups(p<0.001). The TNF-α protein values were approximately fivefold higher in the severe sciatica group than in the mild sciatica group (p<0.01) and the healthy control subjects (p<0.01).The IL-4 protein levels were higher in patients with mild sciatica than in patients with severe sciatica (p= 0.05). The IL-4protein levels were also higher in mild sciatica (p=0.003) and severe sciatica (p= 0.004)groups than in the control subjects. The IL-10 protein values were higher in the severe sciatica group than in the mild sciatica group and the healthy control subjects (p<0.001).ODI was significantly correlated with IL-6 (r= 0.394, p=0.013), TNF-α (r=0.629, p<0.001), and IL-10(r= −0.415, p=0.009). By contrast, ODI was not correlated with IL-4(r= −0.174, p=0.29) and IL-8(r= −0.133, p=0.418). Conclusions: These findings support our hypothesis that sciatica pain is accompanied by the imbalance in inflammatory cytokines.