Introduction:

With an increasing global adoption of spinal cord stimulators (SCS), at approximately 34,000 annual implants (as of 2016), there is a growing need for enhanced perioperative education and tailored guidelines for this patient demographic. This case report underscores a specific instance of IPG device malfunction post spine surgery due to monopolar cautery use, highlighting the necessity for specialized perioperative protocols.

Materials and Methods: The case report is devoid of patient identifiable information, it is thus exempt from IRB review requirements as per Cleveland Clinic institutional policy. She consented to surgery and anesthesia for her SCS revision.

Case Report: 

A 62-year-old female with a history of anxiety, depression, myofascial syndrome, and obesity underwent lumbar decompression in 2016 and posterior L3-L5 lumbar fusion in 2017. She developed failed back surgery syndrome and received a two-lead spinal cord stimulator (SCS) implant with an implantable pulse generator (IPG) in February 2019 following a successful trial.

Despite initial relief, she experienced persistent back pain, later attributed to severe stenosis at L2-3 and ongoing foraminal stenosis at L5-S1. In February 2020, she underwent elective revision, decompression, and fusion extension (L2 to pelvis).

In June 2020, the SCS was revised, explanted, and replaced with a two-lead SCS system, resulting in significant pain relief and improved functionality. In December 2022, she presented with severe tenderness at the IPG site and increased warmth while charging the IPG battery. A battery site revision was recommended, along with a thoracic X-ray to rule out lead migration. X-ray confirmed intact SCS electrodes. Additionally, there was a broken rod and issues with hardware around L2 screws on the right. Spine surgery recommended hardware removal, and it was suggested to address hardware removal before SCS revision.

During the hardware removal procedure in March 2023, monopolar cautery was used to expose the hardware while ensuring lead placement accuracy. Post-surgery, device testing revealed impedances in one lead, rendering it MRI incompatible. In April 2023, thoracic X-ray confirmed intact SCS leads at T8 bilaterally, leading to a plan for lead replacement during the upcoming SCS revision.

At the planned revision, the old leads were replaced with new ones. But there were unsuccessful attempts to achieve lead contact with the old IPG, hence a decision to replace the old IPG with a new one. The leads were inserted into the new IPG, finally resulting in successful lead contact. The IPG pocket was revised and closed, and the procedure went smoothly without complications.

Post-surgery, the patient reported significant pain relief, especially in the right lower extremity, and reduced pain at the IPG site. Warmth around the IPG during charging was resolved.

Discussion: 

Our patient reported an increase in warmth during the IPG device charging, which could have been caused by lead contact issues at the IPG site. 

In this case, monopolar cautery was utilized to expose the spinal hardware during removal, and this might have contributed to device failure in an already suboptimal IPG 2. The use of bipolar cautery may have been a more appropriate choice, and if monopolar electrocautery is to be employed, it should be set at the lowest effective setting. Additionally, the grounding pad should be positioned on the opposite side of the IPG, farthest away from the SCS system. 2

In the era of precision medicine, there is a growing need for tailored education, interventions, and guidelines for patients with SCS who require spinal or non-spinal surgeries. This approach can enhance surgical planning, patient care, and safety. 2,3

Having knowledge about the safety concerns related to SCS and adopting appropriate perioperative evaluation and management strategies for the SCS system can reduce risks and enhance surgical planning.

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