Pulsed Radiofrequency Relieves Neuropathic Pain by Repairing the Ultrastructural Damage of Chronically Compressed Dorsal Root Ganglion.

Abstract

Pulsed radiofrequency (PRF) has demonstrated therapeutic potential for neuropathic pain, yet its efficacy in alleviating pain induced by chronic dorsal root ganglion (DRG) compression remains unclear. This study evaluated the analgesic effects of DRG-targeted PRF in a chronic compression of DRG (CCD) rat model. Adult male Sprague Dawley rats were divided into four groups: sham, CCD, CCD+PRF, and CCD+freePRF. CCD was induced by inserting stainless-steel rods into the intervertebral foramen to compress L4/L5 DRGs. Pain behaviors, including spontaneous pain, mechanical/cold allodynia, and heat hypersensitivity, were assessed pre- and post-PRF treatment. On day 14 post-CCD, DRG ultrastructural changes and myelin basic protein (MBP) expression were analyzed via transmission electron microscopy and immunofluorescence. Compared to sham rats, CCD animals exhibited significant pain behaviors (P < .0001). PRF treatment in CCD+PRF rats significantly attenuated these behaviors (P < .01). Ultrastructural analysis revealed intact myelin sheaths in sham DRGs, whereas CCD DRGs showed myelin damage and reduced MBP expression (P < .01). Notably, PRF repaired myelin structural integrity and restored MBP levels. These findings demonstrate that DRG PRF alleviates neuropathic pain by reversing ultrastructural damage caused by chronic compression, providing mechanistic insights into PRF's analgesic effects and supporting its therapeutic value for neuropathic pain management.