Editor-in-Chief: Alaa Abd-Elsayed, MD, PhD
BACKGROUND: Spinal cord stimulation (SCS) is an evidence-based therapy for intractable chronic back and leg pain (CBLP). Most conventional SCS systems depend on an implantable pulse generator to power the system. The objective of this study was to investigate the efficacy of an externally powered wireless SCS device in patients with CBLP.
CASE REPORT: A total of 29 patients at a single center underwent implantation of a single 8-electrode array epidur¬ally. Responders were defined as having 50% or greater reduction in back and leg pain after a 4-week screening period. At this time, a second electrode array was placed in those patients who responded, percutaneously parallel to the first array.
CONCLUSION: After the 30-day screening period with the single electrode array, 28 of the 29 patients (96.6%) responded with pain relief reduction in Visual Analog Score (VAS) levels between 50% and 90%. Responsive patients were then implanted with the second electrode array. Twenty-six of the 28 (92.8 %) patients who were implanted with 2 leads reported a greater amount of overall pain relief (an additional 15% decrease) once the second device was placed. There were no procedure- or device-related complications in any of the patients. At 12 months follow-up, average VAS scores for back and leg pain did not change significantly from the early results, indicating long-term, sustainable pain relief utilizing the wireless system.
Although a single-electrode array proved to be efficacious, using 2 electrode arrays improves the anatomic coverage of the painful areas and allows for greater optionality in electrode selections to avoid plasticity.
KEY WORDS: Wireless SCS, wireless spinal cord stimulation, wireless pain relief, chronic back pain, chronic leg pain, neuromodulation, high-frequency stimulation