Burst or High-Frequency (10 kHz) Spinal Cord Stimulation in Failed Back Surgery Syndrome Patients With Predominant Back Pain: One Year Comparative Data

Objectives Burst and 10 kHz spinal cord stimulation (SCS) demonstrated improvement for failed back surgery syndrome (FBSS) with predominant, refractory back pain. Here, we report the long-term follow-up of a previously published study comparing the safety and efficacy of burst vs. 10 kHz SCS for predominant back pain (70% of global pain) of FBSS patients. Methods This comparative, observational study extended the follow-up period up to 20 months evaluating both SCS modalities. Pain intensity (visual analog scale [VASB, VASL]), functional capacity (Pittsburgh Sleep Quality Index [PSQI]; depression (Beck Depression Inventory [BDI]), stimulation parameters and hardware and/or stimulation associated adverse events were recorded and analyzed over time. Results Overall VASB (t1,12 = 66.76, p < 0.001) and VASL (t1,12 = 4.763, p < 0.049; p < 0.001) declined over time. Burst significantly decreased VASB by 87.5% (±17.7) (mean 8 ± 0.76 to 1 ± 1.41; t1=12.3, p < 0.001), and 10 kHz significant decreased VASB by 54.9% (±44) (mean 8 ± 0.63 to 3.5 ± 3.27; t1=3.09, p = 0.027). No significant differences for between SCS types were revealed (t1=1.75, p = 0.13). VASL was significantly suppressed for burst (burst: 3.6 ± 1.59 to 1.5 ± 1.06; t1 = 3.32, p = 0.013). A significant effect of time was found for functional outcome with no significant differences between SCS types (PSQI: t1,12 = 8.8, p = 0.012; and BDI: t1 = 53.3, p < 0.001). No stimulation/hardware-related complications occurred. Discussion Long-term data of this comparative study suggests that burst responsiveness was superior to 10 kHz in our small-scale cohort, thus a larger, randomized-controlled comparative study design is highly recommended. Burst and 10 kHz spinal cord stimulation (SCS) demonstrated improvement for failed back surgery syndrome (FBSS) with predominant, refractory back pain. Here, we report the long-term follow-up of a previously published study comparing the safety and efficacy of burst vs. 10 kHz SCS for predominant back pain (70% of global pain) of FBSS patients. This comparative, observational study extended the follow-up period up to 20 months evaluating both SCS modalities. Pain intensity (visual analog scale [VASB, VASL]), functional capacity (Pittsburgh Sleep Quality Index [PSQI]; depression (Beck Depression Inventory [BDI]), stimulation parameters and hardware and/or stimulation associated adverse events were recorded and analyzed over time. Overall VASB (t1,12 = 66.76, p < 0.001) and VASL (t1,12 = 4.763, p < 0.049; p < 0.001) declined over time. Burst significantly decreased VASB by 87.5% (±17.7) (mean 8 ± 0.76 to 1 ± 1.41; t1=12.3, p < 0.001), and 10 kHz significant decreased VASB by 54.9% (±44) (mean 8 ± 0.63 to 3.5 ± 3.27; t1=3.09, p = 0.027). No significant differences for between SCS types were revealed (t1=1.75, p = 0.13). VASL was significantly suppressed for burst (burst: 3.6 ± 1.59 to 1.5 ± 1.06; t1 = 3.32, p = 0.013). A significant effect of time was found for functional outcome with no significant differences between SCS types (PSQI: t1,12 = 8.8, p = 0.012; and BDI: t1 = 53.3, p < 0.001). No stimulation/hardware-related complications occurred. Long-term data of this comparative study suggests that burst responsiveness was superior to 10 kHz in our small-scale cohort, thus a larger, randomized-controlled comparative study design is highly recommended.