title: Spontaneous thoracic spinal cord herniation. A case report.
abstract: METHODS
  This is a case report.
  
  
  OBJECTIVE
  To focus attention on spontaneous spinal cord herniation as a rare cause of myelopathy that can be diagnosed preoperatively and can be corrected surgically.
  
  
  BACKGROUND
  A 34-year-old woman presented with spastic paraparesis. Magnetic resonance imaging scan of the thoracic spine revealed anterior displacement and tethering of the cord at T6-T7 and a dorsal intradural arachnoid cyst. Excision of the cyst was performed without improvement in symptomatology. During reoperation the thoracic spinal cord hernia was discovered and was reduced intradurally.
  
  
  METHODS
  The authors describe the clinical, radiographic, and surgical findings of this patient and review the findings from other reported cases. They discuss the proposed theories for the pathophysiology of the cord herniation and the surgical management.
  
  
  RESULTS
  The patient had idiopathic thoracic spinal cord herniation as there was no history of previous spine surgery or injury. The authors believe that the cord herniated through a congenital dural defect, which resulted in the development of a pseudoarachnoid cyst dorsally to the hernia. The patient improved after intradural reduction of the hernia and closure of the dural defect.
  
  
  CONCLUSIONS
  Idiopathic spinal cord herniation should be recognized as a cause of progressive myelopathy that can be managed successfully with microsurgical techniques.
authors.affiliation: Neurosurgery Service, Memorial Sloan-Kettering Cancer Center, New York, New York, USA.
authors.forename: P
authors.initials: P
authors.lastname: Sioutos
authors.forename: E
authors.initials: E
authors.lastname: Arbit
authors.forename: P
authors.initials: P
authors.lastname: Tsairis
authors.forename: R
authors.initials: R
authors.lastname: Gargan
mesh_terms: D000328:Adult; D018437:Brown-Sequard Syndrome / Q000209:etiology*; D004388:Dura Mater / Q000002:abnormalities* / Q000601:surgery; D005260:Female; D006547:Hernia / Q000473:pathology*; D059685:Herniorrhaphy; D006801:Humans; D008279:Magnetic Resonance Imaging; D013116:Spinal Cord / Q000473:pathology*; D013118:Spinal Cord Diseases / Q000175:diagnosis* / Q000601:surgery; D013904:Thoracic Vertebrae