The Long‐Term Response to High‐Dose Spinal Cord Stimulation in Patients With Failed Back Surgery Syndrome After Conversion From Standard Spinal Cord Stimulation: An Effectiveness and Prediction Study

Objectives Spinal cord stimulation (SCS) is nowadays available with several stimulation paradigms. New paradigms, such as high dose (HD‐)SCS, have shown the possibility to salvage patients who lost their initial pain relief. The first aim of this study is to evaluate the effectiveness of HD‐SCS after conversion from standard SCS. The second aim is to develop a model for prediction of long‐term response of HD‐SCS after unsatisfactory standard SCS. Materials and Methods Seventy‐eight patients with failed back surgery syndrome (FBSS) who are treated with standard SCS were enrolled in the study. Self‐reporting questionnaires and outcomes were assessed before conversion and at 1, 3, and 12 months of HD‐SCS. Longitudinal mixed models were used to determine the effectiveness of HD‐SCS. Logistic regression and classification and decision tree analyses were performed to predict responders (NRS decrease ≥2/10) after 12 months of HD‐SCS. Results Significant time effects were found for both low back and leg pain responders, suggesting the effectiveness of HD‐SCS after conversion. Logistic regression models revealed the importance of pain intensity scores, medication use, paresthesia coverage (for back pain) and EQ5D (for leg pain) as predictors for being a responder after 12 months of HD‐SCS. Conclusions Converting patients with unsatisfactory responses from standard SCS to HD‐SCS may be an effective strategy to obtain and maintain pain relief in a challenging subgroup of patients with FBSS refractory to standard SCS. The prediction models may guide clinicians in their decision making when considering conversion to HD‐SCS in patients with FBSS experiencing inadequate response to standard SCS.