Background & Aims
Lumbar radicular syndrome (LRS) is caused by impairment of spinal sensory nerve roots or dorsal root ganglion (DRG). This trial was planned to assess the efficacy of pulsed radiofrequency (PRF) ablation of the Dorsal root ganglion (DRG) for treating LRS and to demonstrate its effect on Serum Interleukin-6 levels (IL-6). The primary objective was to evaluate Serum IL6 level in LRP patients and compare pre-PRF levels with that of three months post-PRF levels and the secondary objective was to determine the correlation between changes in serum IL-6 levels with pain and disability outcome.
Methods
This was a prospective interventional trial. Thirty-eight patients of LRS aged between 18 and 60 years underwent three cycles of PRF of the DRG at 2 Hz, 42? tip temperature for 180 sec under fluoroscopic guidance. Two blood sample was withdrawn for each patient three months apart for serum IL-6 level evaluation. The outcome parameters assessed was serum IL-6 level, correlation of serum IL-6 with pain (Numerical Rating Scale (NRS)) and disability scores (Modified Oswestry Disability Questionnaire (MODQ)).
Results
IL-6 (pg./mL) decreased significantly from baseline value of 1.43 (0.68) to 0.59 (0.36) at 3 months. Mean NRS significantly reduced from baseline score of 8.11 (0.83) to 3.42 (0.68) at 2 weeks, 3.13 (0.66) at 1-month and 4.08 (0.82) at 3-month with maximum reduction at 1-month. MODQ score reduced to 15.39 (2.70) at 2 weeks, 19.16 (2.94) at 1-month and 24.45 (3.16) at 3-month from the baseline score of 65.18 (6.63). Correlation analysis between IL-6 and NRS & MODQ score was statistically significant (p < 0.001) at baseline. A strong positive correlation (rho = 0.81) was observed between NRS and IL-6 and, moderately positive (r = 0.58) correlation was seen between MODQ score and IL-6. Correlation analysis at 3 months was not statistically significant between NRS and IL-6 level but moderately positive significant correlation was seen between MODQ score and IL-6 (r = 0.35, p = 0.031). Mostly participants reported no procedure-related adverse effects.
Conclusions
The findings suggested the effectiveness of PRF modulation of the DRG in pain alleviation and improving the functional status. The role of Serum IL-6 as a biomarker of disease activity and treatment response is controversial.
References
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