A randomized double-blind clinical trial depicted that the choice of stimulation frequency demonstrates a clear impact on the quality of life, well-being, and pain reduction of the patient with neuropathic pain. G. S. Piedade et al. aimed to determine the effect of mid-frequency dorsal root ganglion stimulation (DRG-S) to alleviate neuropathic pain.

Notably, 19 patients were involved in the trial (mean age: 53 years). The recruited subjects were utilizing DRG-S for a mean of 17.2 months. In a randomized order, subjects having a permanent DRG-S system underwent different phases of stimulation with 80 Hz, 60 Hz, 40 Hz, 20 Hz, and sham. Each phase continued for four days and was subsequently followed by a two-day washout interval. Assessment of quality of life and pain intensity was done utilising Beck Depression Inventory (BDI), EuroQol- 5 Dimension (EQ-5D), visual analog scale (VAS) and McGill Pain Questionnaire (MPQ). The intake of analgesics was also evaluated.

The most frequent pain etiology was chronic regional pain syndrome (CRPS). At baseline, a total of 5 patients were having a PainDetect score of 12 or less. Before the implantation of the system, the mean VAS was 8.6 and 3.9 at baseline. There was a reduction in the pain intensity to 3.7 due to the stimulation with 20 Hz but elevated with greater frequencies reaching 5.8 at 80 Hz. A profound difference between the groups was witnessed in the overall variables investigated (VAS, MPQ, EQ-5D, BDI).

The results at 20 Hz were best for all the variables, including the smallest elevation in pain medication consumption. For the treatment of neuropathic pain of different etiologies, lower stimulation frequencies appeared to be highly efficacious. Additional studies are warranted to assess if the specific frequencies should be preferred on the basis of the condition treated.