Dorsal Root Ganglion Stimulation for the Management of Phantom Limb Pain: A Scoping Review

Background: Amputees commonly feel an intermittent tingling, piercing, or burning sensation in the region of the missing portion of the amputated limb, a phenomenon known as phantom limb pain. Current treatment modalities include medications, mirror therapy, transcutaneous electrical nerve stimulation, and more recently neuromodulation through spinal cord stimulation and dorsal root ganglion (DRG) stimulation. Objectives: The aim of this review is to examine the existing literature to identify and analyze evidence for the use of DRG stimulation as a pain relief modality for phantom limb pain. Study Design: Scoping Review. Methods: A literature search was conducted using relevant search terms. PubMed, Web of Science, Cochrane, and CINAHL databases were used, and reference lists of selected articles were searched for additional relevant literature. Results: Most studies analyzed had low to moderate bias in all categories assessed. There are case reports and case series indicating that DRG stimulation could be an effective treatment method for phantom limb pain. Fifteen of 25 patients across 5 studies achieved satisfactory levels of pain relief and significant improvements were reported by all patients evaluated for quality of life. Patient selection and proper targeting of stimulation are important factors in limiting large variability in results while determining effectiveness of this pain relief modality. Limitations: The studies included in this scoping review are limited by the number of cases and by the length of follow-up. Also, there are no randomized control trials or observational studies with large sample sizes that allow for adequate power. Many of these studies do not have a standardized methodology of quantifying pain relief from DRG stimulation. Conclusions: The cumulative evidence at present suggests DRG stimulation may be a potentially effective treatment for phantom limb pain, however, a powered prospective randomized controlled trial is needed to assess the long-term benefits of this treatment modality. Given the increasing population of military veterans who are living with limb amputations, finding a modality for adequate long-term pain control is crucial.