Single Lead Percutaneous Trial for Dorsal Column Stimulation, a Surgeons Perspective

Introduction: Neuromodulation of pain pathways through dorsal column stimulation has become the preferred treatment for post-laminectomy syndrome and causalgia. Before implanting a permanent device, a patient-specific evaluation is conducted using a percutaneous trial lead and an external pulse generator. This procedure involves inserting electrodes into the thoracic epidural space adjacent to the spinal cord, typically using two eight-lead arrays. This placement maximizes the overlap between pain sensation and paresthesia while avoiding the motor regions of the spine. Patient-specific programming and mapping are then performed with a tonic frequency and waveform (40-80Hz), followed by a multiday trial using high-frequency “burst” stimulation at 500Hz, which provides analgesia without paresthesia. Candidates for permanent stimulation are those whose pain and related symptoms decrease by more than 50% as measured by the Visual Analog Scale (VAS). The placement of a permanent stimulator requires an additional surgery to implant the battery under the skin, and replacement surgery will be needed every few years to change the batteries.

Methods: Retrospective chart review of a single surgeons 1 year experience inserting percutaneous
trial leads.

Results: Over a one- year period 27 patients (17 female, 10 male) underwent spinal cord
stimulation trial. 26 of these were performed with a single lead, one underwent two lead
placement. 26 of 27 (96%) patients proceeded to have permanent systems implanted.

Conclusion : Placement of a single lead provides adequate stimulation to evaluate efficacy of
dorsal column stimulation in the vast majority of patients prior to permanent implantation. Simplification of the trial procedure may reduce expected risks including cerebrospinal fluid leak. Current reimbursement models which pay per lead (CPT 63650 NAP $6,523) should be reviewed and updated.