Improved Pain Control with Combination Spinal Cord Stimulator Therapy Utilizing Sub-perception and Traditional Paresthesia Based Waveforms: A Pilot Study

Amnon A Berger; Ivan Urits; Jamal Hasoon; Jatinder Gill; Musa Aner; Cyrus A Yazdi; Omar Viswanath; Elyse M Cornett; Alan David Kaye; Farnad Imani; Farsad Imani; Giustino Varrassi; Thomas T Simopoulos

doi:10.5812/aapm.113089

Improved Pain Control with Combination Spinal Cord Stimulator Therapy Utilizing Sub-perception and Traditional Paresthesia Based Waveforms: A Pilot Study

Anesth Pain Med. 2021 Feb 22;11(1):e113089. doi: 10.5812/aapm.113089. eCollection 2021 Feb.

Authors

Amnon A Berger¹, Ivan Urits¹, Jamal Hasoon¹, Jatinder Gill¹, Musa Aner¹, Cyrus A Yazdi¹, Omar Viswanath^{2

3

4

5}, Elyse M Cornett⁵, Alan David Kaye⁵, Farnad Imani⁶, Farsad Imani⁷, Giustino Varrassi⁸, Thomas T Simopoulos¹

Affiliations

¹ Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA.
² Department of Anesthesiology, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, USA.
³ Department of Anesthesiology, Creighton University School of Medicine, Omaha, NE, USA.
⁴ Valley Anesthesiology and Pain Consultants-Envision Physician Services, Phoenix, AZ, USA.
⁵ Department of Anesthesiology, LSU Health Shreveport, Shreveport, LA, USA.
⁶ Pain Research Center, Department of Anesthesiology and Pain Medicine, Iran University of Medical Sciences, Tehran, Iran.
⁷ Department of Anesthesiology, Tehran University of Medical Sciences, Tehran, Iran.
⁸ Paolo Procacci Foundation, Roma, Italy.

Abstract

Background: Chronic back and neck pain affects 20% of Americans. Spinal cord stimulation (SCS) is an effective therapy for otherwise refractory chronic pain. Traditional SCS relies on low-frequency stimulus in the 40 - 60 Hz range causing robust paresthesia in regions overlapping with painful dermatomes.

Objectives: This study aims to determine the effect of superimposing sub-perception stimulation in patients who previously had good long-term relief with paresthesia.

Methods: This is a prospective observational trial examining patients who had previously been implanted with paresthesia based SCS for failed back surgery syndrome (FBSS) or complex regional pain syndrome (CRPS). These patients presented for implantable pulse generator (IPG) replacement based on battery depletion with an IPG capable of combined sub-perception and paresthesia based SCS therapy. Patients were assessed immediately following the exchange and four weeks later using a telephone survey. Their pain was assessed on each follow up using a Numerical Rating scale (NRS); the primary outcome was the change in NRS after four weeks from the exchange day. Secondary outcomes included paresthesia changes, which included the subjective quality of sensation generated, the overall subjective coverage of the painful region, subjective variation of coverage with positional changes, and global perception of the percentage improvement in pain.

Results: Based on our clinic registry, 30 patients were eligible for IPG exchange, 16 were consented for follow up and underwent an exchange, and 15 were available for follow up four weeks following. The average NRS decreased from 7.47 with traditional SCS to 4.5 with combination therapy. 80% of patients reported an improvement in the quality of paresthesia over traditional SCS therapy, and in most patients, this translated to significantly improved pain control.

Conclusions: Our findings suggest improved pain relief in patients who had previously had good results with paresthesia based therapy and subsequently underwent IPG exchange to a device capable of delivering combined sub-perception stimulation. The mechanism of action is unclear though there may be an additive and/or synergistic effect of the two waveforms delivered. Larger studies with long-term follow-up are needed to elucidate the durability of pain relief and the precise mechanism by which combined subperception and paresthesia based SCS may improve overall patient outcomes.

Keywords: Back Pain; Chronic Pain; Combination Multi-wave Form; Complex Regional Pain Syndrome; Failed Back Surgery Syndrome; Paresthesia, Subperception Neurostimulation; Spinal Cord Stimulation.