Stimulation of the Spinal Cord and DorsalNerve Roots for Chronic Groin, Pelvic, andAbdominal Pain

Background: Chronic neuropathic groin pain is a common problem. It can arise following surgery or trauma, or spontaneously as part of various pelvic pain syndromes. A number of different stimulation techniques have been reported in the literature to treat this area, but due to the complex anatomy of the region, it can be difficult to target effectively with paresthesias. Objectives: In this study we report our results treating patients with chronic neuropathic groin, pelvic, and abdominal pain, using spinal cord stimulation and dorsal nerve root stimulation. Study Design: Open label, prospective study that includes all patients treated with a new trial stimulator system at a single center between July 1, 2011, and October 31, 2013. Setting: Academic university neurosurgical pain center, Canada. Methods: Thirty-two patients had trials of spinal cord stimulation and/or dorsal nerve root stimulation in the thoracic or lumbar spine. Patients were evaluated on visual analog scale pain scores, SF-36, and morphine equivalent daily dose. Data were recorded at the pre-implant visit, and 3, 6, and 12 months following permanent implant. Results: The 15 patients who went on to permanent implants had, on average, significant pain reduction and improvements in quality of life at the 12 month follow-up. The majority of patients who were taking opioids at the initial assessment were able to reduce their dose with treatment. Three patients with successful trials were long-term non-responders, of whom 2 had the permanent device removed. Limitations: This study would benefit from a larger sample size that would have adequate power for comparisons between patient subgroups and stimulation techniques. Conclusion: Dorsal nerve root stimulation is an effective long-term treatment for neuropathic groin pain. Key words: Spinal cord stimulation, nerve root stimulation, lumbar, thoracic, neuropathic pain, groin pain, pelvic pain, abdominal pain, neuromodulation, clinical effectiveness