Factors Contributing to Spinal Cord Stimulation Outcomes for Chronic Pain

OBJECTIVE Spinal cord stimulation (SCS) has been shown to be a safe and effective therapy for patients with chronic pain. However, some patients do not obtain or maintain adequate pain relief after SCS. The goal of this study was to identify factors that affect patient outcome with regard to SCS. MATERIALS AND METHODS A retrospective analysis of electronic medical records at a single site was performed. Records for 181 patients who received SCS implants from 2014 through 2016 were collected with follow-up data captured up to August 2019. Patient outcome was measured by device explantation and patient benefit from the SCS. Study parameters included demographic characteristics, history of pain, SCS implant characteristics, and postimplantation events. RESULTS An earlier diagnosis of radiculopathy was associated with an increased risk of poor benefit (relative risk [RR], 1.81; 95% CI, 1.19-2.74; p = 0.008). Postimplantation falls were associated with an increased risk of poor benefit (RR, 2.17; 95% CI, 1.48-3.17; p = 0.009). Device manufacturer was associated with both patient benefit and explantation. Device 2 was associated with a reduced risk of poor benefit (RR, 0.52; 95% CI, 0.32-0.85; p = 0.009). Device 4 was associated with an increased risk of poor benefit (RR, 1.71; 95% CI, 1.14-2.55; p = 0.02) and increased risk of device explantation (RR, 2.69; 95% CI, 1.2-6.02; p = 0.03). CONCLUSIONS Patient outcome was associated with diagnosis, postimplantation falls, and device manufacturer. Further investigation is recommended to confirm associations through prospective studies that can more accurately quantify patient outcome over longer periods.