Intradural Fibrosis Following Percutaneous Spinal Cord Stimulator Placement: A Case Report

Introduction: Spinal cord stimulation (SCS) is an established therapy for chronic pain. While hardware complications such as lead migration or infection are well-documented, biological responses such as fibrotic encapsulation are rare and underrecognized. Prior reports of fibrosis related to SCS have been limited to the epidural space, primarily involving paddle leads. We report the first known case of intradural fibrotic scarring following percutaneous SCS implantation, resulting in delayed spinal cord compression and progressive neurologic decline. Clinical Presentation: A 69-year-old woman with a history of thoracic percutaneous SCS placement presented with progressive lower extremity sensory loss, weakness, and urinary retention 7 years after implantation. MRI demonstrated a spinal cord signal change centered around a T9–10 lesion at the level of the leads. During surgery, dense fibrotic tissue was noted both epidurally and intradurally, tightly encasing and tethering the spinal cord. No distinct dural plane was observed at the site of maximal compression. A durotomy was required to perform microsurgical dissection intradurally and release the spinal cord. Histopathological analysis revealed dense hyalinization, chronic lymphohistiocytic infiltration, and focal metallic material deposition, consistent with a chronic foreign body reaction. Conclusion: This represents the first documented case of SCS-associated fibrosis extending intradurally, highlighting a novel and serious complication. Clinicians should maintain vigilance for delayed neurologic decline in patients with long-standing SCS systems and consider open decompression when percutaneous explantation is not feasible.