ABSTRACT
Background: Treating chronic pain using sub-perception Spinal Cord Stimulation (SCS) does not elicit paresthesia but is associated with long analgesic 'wash-in' (i.e. duration until maximum pain relief) and prolonged assessment of therapy. We describe the attainment of clinically meaningful and rapid-onset analgesic outcomes using a novel sub-perception SCS approach.Methods: This observational case-series evaluated patients implanted with an SCS device for chronic pain, who underwent re-programming utilizing a new methodology in which paresthesia was used to guide sub-perception stimulation field targeting at specific parameters including charge-balanced symmetrical pulses at 90 Hz (termed Fast-Acting Sub-Perception Therapy, FAST). Pain scores (NRS) were collected as reported per standard-of-care from patient charts.Results: Mean overall pain score at baseline was 8.4 ± 0.2 (n = 41). After activation of FAST, a 7.1-point reduction in overall pain score was (1.3 ± 0.2, p < 0.0001) reported within 11.2 ± 1.9 minutes (n = 34). This decrease in pain score was sustained out to 3-month (1.6 ± 0.3, n = 26) and 6-month follow-up (1.7 ± 0.4, n = 18). At last follow up (mean = 223 ± 132 days), a pain score of 1.6 ± 0.3, n = 30 was determined.Conclusions: After FAST implementation, a profound analgesic response, requiring substantially less energy than conventional sub-perception methodologies, was observed. This rapid analgesic onset achieved with the novel FAST technique suggests the potential for an alternative mechanism of action(s) of sub-perception SCS.
