PGY-4 Neurosurgical Resident Albany Medical College Albany, New York, United States
Introduction: Prior to permanent implant of a spinal cord stimulator, patients typically undergo a screening trial using a percutaneously placed lead to ensure adequate response. However, due to several factors, patients may not be candidates for this screening trial and undergo a permanent trial where either a percutaneous lead or paddle lead is permanently placed. If these patients proceed with implant, the epidural space is not re-accessed and only an impulse generator (IPG) is needed. Although this is a common technique, there is an absence of clinical experience with this technique in the literature. Here we present our experience with permanent trials.
Methods: Participants who underwent permanent trials between at a single institution between 2014-2020 were reviewed. Charts were reviewed to collect demographic information, numerical rating score (NRS) data, length of follow-up, revisions, complications, and removals.
Results: A total of 27 patients who underwent permanent trial placement were identified from a database of 762 patients who underwent SCS placement (3.54%). This included 7 paddle trials and 14 percutaneous trials, and 6 dorsal root ganglion (DRG) trials. 24/27 (88.8%) proceeded to permanent implant and 16/24 (66.7%) were considered responders (greater than 50% reduction in pain) after 3 months. Over an average follow-up of 28.7 months, there was one peri-operative hemorrhage delaying IPG placement, 2 lead fractures, 1 lead migration, and 1 CSF leak. Three patients required revision surgery for lead migration, lead fracture, and CSF leak. One patient had his system explanted 25.9 months after initial placement due to increased pain from stimulation.
Conclusion : This study aims to characterize our experience with permanent trials for SCS. Here we demonstrate a higher rate of trial-to-implant conversion than previous documented for traditional percutaneous trials with similar rates of revisions and complications, demonstrating the important role for this technique in high-risk patients.
