High Frequency (10 kHz) or Burst Spinal Cord Stimulation in Failed Back Surgery Syndrome Patients With Predominant Back Pain: Preliminary Data From a Prospective Observational Study

Background: Conventional spinal cord stimulation (SCS) exhibits pain relief and improved quality of life in refractory failed back surgery syndrome. However, patients suffering from predominant back pain failed to achieve a favorable neuromodulation outcome. Currently, two new stimulation concepts, the burst and the HF10 stimulation paradigms successfully suppress intractable back pain levels in this difficult-to-treat subgroup. To date, literature data comparing both stimulation patterns is lacking. Methods: A prospective, observational study was conducted including 16 refractory Failed-back surgery syndrome (FBSS) patients with previous spine surgery and predominant back pain (70% of overall pain) with or without leg pain eligible for burst or high-frequency SCS. At baseline and at a three-month follow-up the pain intensity (back pain (VAS(B))/leg pain (VAS(L)), sleep quality (Pittsburgh Sleep Quality Index [PSQI]), changes in severity of depressive symptoms (Beck Depression Inventory [BDI]) and any adverse event related to the implantation and the stimulation were recorded. Results: Overall baseline VAS(B) was significantly suppressed in 14 FBSS patients (eight burst/six patients with 10 HF10) from baseline 7.9 +/- 0.7 to 2.3 +/- 1 (p<0.001), while the overall VAS(L) declined significantly from 3.1 +/- 1.5 to 1.9 +/- 0.83 (p<0.01). The burst patients experienced significant VAS(L) reduction (burst 1.8 +/- 0.7 (p<0.009) compared to HF10 patients 2.2 +/- 1). Two patients failed 10 HF10-trial. The BDI [23.3 +/- 2.1 to 13.5 +/- 4.5 (p<0.001)] and the PSQI [7.6 +/- 3.7 to 4.2 +/- 1.4 (p<0.003)] dropped down significantly for both modalities. No implantation/stimulation-related complications were observed. Conclusions: Burst and HF10 SCS performed efficiently and safely in intractable FBSS patients with predominant back pain and deserve more refined, specific investigations to determine their efficacy.