The objective of this study is to retrospectively evaluate the efficacy of dorsal root ganglion (DRG) stimulation in treating painful hereditary and idiopathic axonal polyneuropathy.

Dorsal root ganglion (DRG) stimulation has been demonstrated to be effective in treating painful diabetic polyneuropathy in a small case series. However, diabetic polyneuropathy only accounts for 41% of all polyneuropathies and the efficacy of DRG on other types of polyneuropathy is unclear.  

This is a monocentric retrospective case series. Two subjects with painful hereditary axonal polyneuropathy and two subjects with painful chronic idiopathic axonal polyneuropathy who underwent DRG stimulation trials were included in this study. All subjects were evaluated independently by neuromuscular neurologists with eletrophysiological studies and genetic testing. Permanent DRG stimulator was implanted if significant pain relief (>50%) was achieved over the trial period. Pain level were evaluated at baseline, during the trial, after the permanent implantation and at each follow up.    

Pain was significantly reduced after the DRG stimulator trial with an average VAS reduction of 6.00±2.83, or 65±26.77% (P=0.024). Three subjects subsequently underwent permanent DRG stimulator implantation. Pain remained significantly reduced after the permanent implantation. The average VAS reduction was 6.33±2.31, or 67.5±20.46% after permanent DRG implantation (P=0.042), 7.67±2.31, or 80.83±15.88% at 1 month (P=0.029), and 7.00±2.00 or 74.17±14.21% at 3 months (P=0.026). No complications were observed.

This small retrospective study suggests that DRG stimulation may be a safe and effective treatment for painful hereditary and idiopathic axonal polyneuropathy.