Surgical management of recurrent spinal hypertrophic pachymeningitis: illustrative case

BACKGROUND: Spinal hypertrophic pachymeningitis is a rare manifestation of immunoglobulin G4 (IgG4)-related disease. This condition presents significant diagnostic and therapeutic challenges, and the literature on its surgical management remains limited. OBSERVATIONS: A 55-year-old woman with fibromyalgia and a 20-pack-year smoking history presented with 3 months of worsening back pain, lower extremity weakness, and numbness, corresponding to a modified Japanese Orthopaedic Association (mJOA) score of 10 at presentation. MRI revealed a mass-like epidural process spanning T1-5 with cord compression. Decompression was achieved with T1-5 laminectomies, during which dura mater thickening was observed and subsequently debulked. Pathology revealed findings consistent with possible IgG4 pachymeningitis. While the patient initially regained full strength in her lower extremities with surgery and medical management, she required a second surgery due to recurrent symptoms and renewed compression and dural thickening. She underwent a second dural debulking and decompression with duraplasty, which alleviated her recurrent symptoms. She remained free of recurrent symptoms at her 1-year postoperative follow-up, with an mJOA score of 17. LESSONS: This case demonstrates the effective use of a multidisciplinary team and recurrent surgical management, incorporating adjuncts such as intraoperative ultrasound and dural patch closure in the management of pachymeningitis causing significant cord compression, ultimately leading to lasting positive clinical improvement. https://thejns.org/doi/10.3171/CASE25313.