Myelopathy in the Setting of a Spinal Cord Stimulator for Low Back: A Case Report

Case Diagnosis: 51-year-old man with myelopathy secondary to thoracic spinal stenosis.

Case Description or Program Description: The patient was seen for progressing back and leg pain that was being managed by a spinal cord stimulator implanted in the thoracic spine 15 years prior to address degenerative lumbar spinal stenosis. The battery was replaced, and symptoms were effectively managed until 3 more years passed with the reoccurrence of the pain with new lower extremity symptoms. New imaging was taken of the lumbar spine, and no changes were documented. Patient was treated with an epidural and nerve block injections, but symptoms did not resolve. In addition, patient started to experience increased urinary urgency, progressive paresthesia in both legs, and had difficultly plantarflexing on the floor. Upon neurological examination, patient demonstrated ankle clonus and hyperreflexia in knee and ankle (3+), demonstrating upper motor neuron injury. Furthermore, subtle signs showing functional decline with walking, standing time, and sit-to-stand difficultly were present. A CT scan of the thoracic spine was ordered, revealing spinal stenosis and compression at the T10/11 level. Patient was advised to remove the spinal cord stimulator through surgery and undergo thoracic decompression.

Setting: Outpatient private practice.

Assessment/Results: Patient followed up 6 weeks post-surgery and expressed satisfaction with almost complete resolution of symptoms. Patient stated that the paresthesia was resolved in both lower extremities, his bladder function improved significantly, and the “burning” sensation in his lower back was resolved. Monitoring for pain related to lumbar stenosis will be conducted in the future.

Discussion (relevance): Myelopathy with presentation of upper motor neuron signs after spinal cord stimulator implant is a rare complication that has been sparsely documented in literature, so thorough examination is needed to accurately diagnose this condition.

Conclusions: Upper and lower motor neuron signs should be utilized in examination during follow up in patients with spinal cord stimulator presenting with increased low back pain.