Spinal stimulator peri-electrode masses: case report

Abstract

<jats:p>The authors describe a case of delayed spastic quadriparesis caused by a peri-electrode mass following the implantation of a minimally invasive percutaneous spinal cord stimulator (SCS). Prior reports with paddle-type electrodes are reviewed, and a detailed histological and pathophysiological comparison with the present case is made.</jats:p> <jats:p>The patient developed tolerance to a cervical percutaneous SCS 4 months after implantation, followed by the onset of spastic quadriparesis 9 months after implantation. The stimulator was removed, and contrast-enhanced MRI revealed an enhancing epidural mass where the system had been placed, with severe spinal cord compression. Decompression was carried out, and the patient experienced neurological improvement. Pathological examination revealed fibrotic tissue with granulomatous and multinucleated giant cell reactions. No evidence of infection or hemorrhage was found. Professionals treating patients with SCSs or contemplating their insertion should be aware of this delayed complication and associated risk factors.</jats:p>

Osteolysis and Cervical Cord Compression Secondary to Silicone Granuloma Formation around a Dorsal Spinal Cord Stimulator: A Case Report

“…The phenomenon of tolerance is one that has been previously documented in reports of patients who have had thickened fibrous scar tissue develop around their SCS, causing cord compression symptoms. 6 …”

“…A search of the published literature showed that only seven documented cases have been reported. 2 3 4 5 6 7 In each case the SCS was implanted for various intractable pain conditions that initially resolved but were later characterized by decreasing pain control (tolerance) and progressive neurological deficits (weakness, spastic quadriparesis among others). Neurologic deficits improved after removal of the SCS and decompression of the spinal cord and removal of the accumulated scar tissue.…”

Rate of perioperative neurological complications after surgery for cervical spinal cord stimulation

“…It is important to note, that the present rate of neurological injury refers only the immediate postoperative period. Rates of neurological injury due to cSCS will be even higher with known long-term neurological complications of cSCS including remote spinal cord injury from stimulator mass effect, 9 local tissue reaction causing cord injury, 5,16,21,30,34 and lead migration. Aside from direct cord injury, and epidural hematoma, associated neurological deficits remain a concern after cSCS and are described in case reports.…”

The Neurostimulation Appropriateness Consensus Committee (NACC) Safety Guidelines for the Reduction of Severe Neurological Injury

“…As foreign bodies, SCS leads may be expected to create a host reaction. Adverse outcomes due to epidural fibrosis and/or peri‐SCS lead granulomatous masses have been reported . Recently, Scranton et al reported a case of loss of stimulation efficacy followed by the development of spastic quadriparesis in a patient with a percutaneous cervical spine SCS lead .…”