title: Operative treatment of anterior thoracic spinal cord herniation: three new cases and an individual patient data meta-analysis of 126 case reports.
abstract: OBJECTIVE
  Anterior thoracic spinal cord herniation is a rare cause of progressive myelopathy. Much has been speculated about the best operative treatment. However, no evidence in favor of any of the promoted techniques is available to date. Therefore, we decided to analyze treatment procedures and treatment outcomes of anterior thoracic spinal cord herniation to identify those factors that determine postoperative outcome.
  
  
  METHODS
  An individual patient data meta-analysis was conducted, focusing on age, gender, vertebral segment of herniation, preoperative neurological status, operative interval, operative findings, operative techniques, intraoperative neurophysiological monitoring, postoperative imaging, neurological outcome and follow-up. Three cases from our own institution were added to the material collected. Bivariate analysis tests and multivariate logistic regression tests were used so as to define which variables were associated with outcome after surgical treatment of anterior thoracic spinal cord herniation.
  
  
  RESULTS
  Brown-Séquard syndrome and release of the herniated spinal cord appeared to be strong independent factors, associated with favorable postoperative outcome. Widening of the dura defect is associated with the highest prevalence of postoperative motor function improvement when compared with the application of an anterior dura patch (P < 0.036).
  
  
  CONCLUSIONS
  Most patients with anterior thoracic spinal cord herniation require operative treatment because of progressive myelopathy. Patients with Brown-Séquard syndrome have a better prognosis with respect to postoperative motor function improvement. In this review, spinal cord release and subsequent widening of the dura defect were associated with the highest prevalence of motor function improvement. D-wave recording can be a very useful tool for the surgeon during operative treatment of this disorder.
authors.affiliation: Department of Neurosurgery, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands. r.j.m.groen@nchir.umcg.nl
authors.forename: Rob J M
authors.initials: RJ
authors.lastname: Groen
authors.forename: Berrie
authors.initials: B
authors.lastname: Middel
authors.forename: Jan F
authors.initials: JF
authors.lastname: Meilof
authors.forename: J B Margot
authors.initials: JB
authors.lastname: de Vos-van de Biezenbos
authors.forename: Roelien H
authors.initials: RH
authors.lastname: Enting
authors.forename: Maarten H
authors.initials: MH
authors.lastname: Coppes
authors.forename: Louis H
authors.initials: LH
authors.lastname: Journee
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006547:Hernia / Q000175:diagnosis; D059685:Herniorrhaphy; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009460:Neurologic Examination; D019635:Neurosurgical Procedures; D010292:Paresthesia / Q000209:etiology; D011183:Postoperative Complications / Q000453:epidemiology / Q000503:physiopathology; D013118:Spinal Cord Diseases / Q000175:diagnosis / Q000601:surgery*; D013904:Thoracic Vertebrae / Q000473:pathology / Q000601:surgery; D016896:Treatment Outcome; D055815:Young Adult