359 - Treatment of Neuropathic Pain by Sensory Nerve Stimulation of the Lumb...

#359 Treatment of Neuropathic Pain by Sensory Nerve Stimulation of the Lumbar Exiting Nerve DRG Using a Percutaneous Transforaminal Approach

Cutting Edge Innovations/Non-conventional Therapies

Poster Presented by: A.T. Yeung

Author(s):

A.T. Yeung (1,2)
L.T. Perryman (2)

(1) Desert Institute for Spine Care, Phoenix, AZ, United States
(2) Stimwave Technologies, Scottsdale, AZ, United States

Abstract

Introduction: Epidural Spinal column stimulation (SCS) is used to salvage FBSS. Traditional wired spinal cord stimulator technology has become increasingly costly to implement; resulting from the need for a separate procedure for trial lead placement which is at the very least repeated for permanent implantation or referred to a surgical laminotomy to place the typical wired lead, extension tunneling from the lead, and the cost of the implantable pulse generators with on board batteries which last less than four years before requiring surgical revision on average. A novel wireless power platform has been developed to augment the paradigm, which allows for wireless power through the skin. This wireless lead allows for reduced risk of infection in the trial setting by eliminating the open port percutaneous lead of conventional systems. Long term, no secondary permanent procedure or surgery is necessary, nor tunneling an extension to an IPG which also eliminates various risks of infection and provides a more time efficient method of treatment with less implantable system components.

This study investigated the advantages of direct nerve placement of a wirelessly powered Sensory Nerve Stimulator (SNS) placed transforaminally by the DRG of the painful spinal segment.

Method: Five FBSS patients with back and leg pain were implanted with a SNS lead containing four electrodes. A 14 gauge Tuohy needle guided the lead percutaneously to the axilla of the exiting and traversing nerve by the DRG. After functional verification of pain relief stimulation, the needle is removed and the lead's tubing is anchored subdermally. The SNS lead is not anchored. Patients continue the stimulation at home for up to 30 days before explantation. Anterior-posterior and lateral X-rays were used every three days to monitor lead migration.

Results: All five patients reported successful stimulation as defined by at least 50% reduction of VAS and 50% paresthesia coverage of the pain distribution area. Baseline VAS score averaged 8.5 to 2.3 by the end of the trial period. Lead migration ranqed from 1.1 mm to 5.4 mm after 30 days.

Discussion: Placement of a SNS directly to the DRG is closer to the pain source compared to traditional epidural SCS. Patients with bilateral pain that received only one SNS lead on one side of the dorsal column only reported one-side coverage of their total pain area. This suggests that optimal treatment and complete coverage may require multi-level or bilateral stimulator placements. The patient with dual lead placement had close to 100% pain relief coverage. Although lead migration was observed in all patients, the SNS electrode coverage area overcompensated for any migration effects.

Wirelessly powered SNS enables direct transforaminal implantation of the lead closer to the pain generator in FBSS patients. Wireless SNS is a practical and simplified therapy that may provide a viable, minimally invasive treatment option for chronic low back and/or leg pain from FBSS.