Thoracic Radiculopathy and Abdominal Pain Associated with Smaller Canal Diameters Following Spinal Cord Stimulator (SCS) Paddle Lead Placement

Introduction: Thoracic radiculopathy and abdominal pain are not infrequent patient complaints following thoracic spinal cord stimulator (SCS) paddle lead implantation.[1, 2, 4] Previously, we have shown that smaller thoracic canal diameters are associated with post-operative neurologic deficits.[3] This study compared thoracic spinal canal diameters of patients with and without new thoracic radiculopathy (TR) and abdominal pain (AP).

Methods: Patients undergoing thoracic laminotomy for new SCS paddle lead placement were identified from January 2018 to September 2023. Preoperative thoracic canal diameter was measured in the sagittal plane perpendicular to the disc space from T5/6 to T11/12 (Figure 1). A comparison of canal diameters between patients with and without post-operative neurologic deficit, thoracic radiculopathy, and abdominal pain was performed using the statistical Mann-Whitney, two-tailed, unpaired, nonparametric U-test (Prism 9, GraphPad Software).

Results: 206 patients underwent thoracic laminotomy for SCS placement (Table 1). Thoracic radiculopathy and abdominal pain occurred in 3.4% (7/206), and 3.4% (7/206) among patients, respectively. Mean canal diameter of patients without complaint, thoracic radiculopathy and abdominal pain were 12.9 mm, 9.83 mm (P < 0.0001), 11.6 mm (P < 0.0001), and 12.1 mm (P < 0.02), respectively (Figure 2).

Conclusion : Post-operative thoracic radiculopathy, and abdominal pain are associated with a smaller thoracic canal diameter. If canal diameter is < 12 mm, aggressive undercutting of the lamina or a second laminotomy should be considered.

References:
1. Ghosh, R., R. Holland, and A. Mammis, Thoracic Radiculopathy following Spinal Cord Stimulator Implantation Treated with Corticosteroids. World Neurosurg, 2017. 100: p. 712 e1-712 e4.
2. Baranidharan, G., B. Bretherton, and S. Black, A case series of new radicular pain following the insertion of spinal cord stimulator. Br J Pain, 2022. 16(4): p. 450-457.
3. Ragel, B.T., et al., Analysis of spinal canal diameter in the placement of thoracic spinal cord stimulator paddle leads. Pain Pract, 2023.
4. Zemmar, A., et al., Ogilvie's syndrome after paddle spinal cord stimulator implantation: An experience report. Pain Pract, 2023. 23(6): p. 684-688.