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 Two blood sample was withdrawn for each patient three months apart for serum IL-6 level evaluation.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

1.Deyo RA, Tsui-Wu YJ. Descriptive epidemiology of low-back pain and its related medical care in the United States. Spine (Phila Pa 1976). 1987;12(3):264–8.
2.Weber KT, Alipui DO, Sison CP, Bloom O, Quraishi S, Overby MC et al. Serum levels of the proinflammatory cytokine interleukin-6 vary based on diagnoses in individuals with lumbar intervertebral disc diseases. Arthritis Res Ther. 2016; 18:3.
3.Das B, Conroy M, Moore D, Lysaght J, McCrory C. Human dorsal root ganglion pulsed radiofrequency treatment modulates cerebrospinal fluid lymphocytes and neuroinflammatory markers in chronic radicular pain. Brain Behav. Immun. Feb 2018; 70:157-65.
4. Haddadi K, Abediankenari S, Alipour A, Ghazvini HRG, Jafarpour H, Asadian L et al. Association between Serum Levels of Interleukin-6 on Pain and Disability in Lumbar Disc Herniation Surgery. Asian J Neurosurg. 2020;15(3):494-8.

Presenting Author

Sonal Goyal

Poster Authors

Sonal Goyal

MD

MGM MEDICAL COLLEGE & HOSPITAL, KAMOTHE

Lead Author

Ajit Kumar

MD

AIIMS, Rishikesh

Lead Author

Topics

  • Models: Chronic Pain - Neuropathic