First Report of Extraspinal Lead Migration Along a Thoracic Spinal Nerve After Spinal Cord Stimulation

Spinal cord stimulation for failed back surgery syndrome and chronic pain is a well-established treatment regimen today. Lead migration is the most common complication; mainly epidural caudal more than cranial electrode migration from the primary position is described repeatedly throughout the literature.

A 60-year-old male patient with failed back surgery syndrome was eligible for spinal cord stimulation. Surgery had been performed 4 weeks before readmission with proper lead positioning of both electrodes in the midline of the epidural space. The electrode fixation mechanism at L2/3 had to be revised and was replaced with multiple ligature fixations due to the patient's slim build. He presented to our outpatient clinic with thoracic right-sided pain matching T5 with signs of overstimulation of the paravertebral muscles. X-ray imaging revealed cranial migration of 1 lead to T4 and a right-sided extraspinal migration of the other lead along a spinal nerve in T5 exiting the neuroforamen and following beneath the corresponding rib dorsally. Revision surgery was performed using a thoracic paddle electrode.

Lead migration remains a challenge in spinal cord stimulation regardless of the fixation method. Rare unusual migration patterns in addition to simple caudal or cranial migration might pose a challenge for revision surgery and thus might reduce overall treatment efficacy.