Lumbar spinal stenosis exacerbated by spinal epidural lipomatosis: a case report

Objective: To characterize the presentation, diagnostic strategy, and postoperative recovery patterns in a patient with lumbar spinal stenosis (LSS) complicated by spinal epidural lipomatosis (SEL), and to evaluate the role of selective nerve root block (SNRB) in guiding staged minimally invasive decompression. Methods: We analyzed the clinical course of a 65-year-old man presenting with neurogenic claudication and right lower extremity numbness after a course of inhaled glucocorticoids. Preoperative assessment included radiography, computed tomography (CT), and magnetic resonance imaging (MRI), which demonstrated degenerative central canal stenosis at L4/5 and epidural lipomatosis at L5/S1. Because imaging findings were multilevel and symptom dominance was unclear, SNRB localized the symptomatic level and guided staged arthroscopy-assisted uniportal decompression. Clinical outcomes were assessed using the Visual Analog Scale (VAS), Oswestry Disability Index (ODI), SF-36 quality-of-life scores, walking tolerance, and neurological examinations during 4 months of follow-up. Results: SNRB identified L4/5 as the primary symptomatic level, supporting initial targeted decompression. Following Stage 1 decompression at L4/5, neurogenic claudication and motor weakness improved rapidly, with VAS decreasing from 7 to 4 and ODI improving from 52 to 38. Persistent plantar numbness prompted Stage 2 decompression with excision of excessive epidural fat at L5/S1, after which VAS further decreased to 2 and ankle plantarflexion strength improved relative to baseline. At the final follow-up, ODI improved to 20 and the SF-36 composite score increased from 32.6 to 70.8. Walking tolerance markedly improved, only mild plantar paresthesia persisted. No perioperative complications or postoperative instability were observed. Conclusions: This case suggests that SEL may trigger or unmask clinical symptoms of degenerative LSS and highlights distinct recovery trajectory between focal degenerative stenosis and diffuse epidural fat-related compression. SNRB-guided staged minimally invasive decompression enabled precise level selection and favorable functional outcomes, underscoring its value in managing multilevel lumbar pathology complicated by SEL.