title: The lumbosacral angle does not reflect progressive tethered cord syndrome in children with spinal dysraphism.
abstract: OBJECTIVE
  Our goal was to validate the hypothesis that the lumbosacral angle (LSA) increases in children with spinal dysraphism who present with progressive symptoms and signs of tethered cord syndrome (TCS), and if so, to determine for which different types and/or levels the LSA would be a valid indicator of progressive TCS. Moreover, we studied the influence of surgical untethering and eventual retethering on the LSA.
  
  
  METHODS
  We retrospectively analyzed the data of 33 children with spinal dysraphism and 33 controls with medulloblastoma. We measured the LSA at different moments during follow-up and correlated this with progression in symptomatology.
  
  
  RESULTS
  LSA measurements had an acceptable intra- and interobserver variability, however, some children with severe deformity of the caudal part of the spinal column, and for obvious reasons those with caudal regression syndrome were excluded. LSA measurements in children with spinal dysraphism were significantly different from the control group (mean LSA change, 21.0° and 3.1° respectively). However, both groups were not age-matched, and when dividing both groups into comparable age categories, we no longer observed a significant difference. Moreover, we did not observe a significant difference between 26 children with progressive TCS as opposed to seven children with stable TCS (mean LSA change, 20.6° and 22.4° respectively).
  
  
  CONCLUSIONS
  We did not observe significant differences in LSA measurements for children with clinically progressive TCS as opposed to clinically stable TCS. Therefore, the LSA does not help the clinician to determine if there is significant spinal cord tethering, nor if surgical untethering is needed.
authors.affiliation: Department of Neurosurgery, Maastricht University Medical Center, 6202 AZ, Maastricht, The Netherlands. e.cornips@mumc.nl
authors.forename: Erwin M J
authors.initials: EM
authors.lastname: Cornips
authors.forename: Femke G E M
authors.initials: FG
authors.lastname: Razenberg
authors.forename: Lodewijk W
authors.initials: LW
authors.lastname: van Rhijn
authors.forename: Dan L H M
authors.initials: DL
authors.lastname: Soudant
authors.forename: Elisabeth P M
authors.initials: EP
authors.lastname: van Raak
authors.forename: Jacobiene W
authors.initials: JW
authors.lastname: Weber
authors.forename: Simon G
authors.initials: SG
authors.lastname: Robben
authors.forename: Johanna M
authors.initials: JM
authors.lastname: Fock
authors.forename: Coriene E
authors.initials: CE
authors.lastname: Catsman-Berrevoets
authors.forename: Johannes S H
authors.initials: JS
authors.lastname: Vles
mesh_terms: D005260:Female; D006801:Humans; D007223:Infant; D008161:Lumbosacral Region / Q000033:anatomy & histology*; D008297:Male; D009436:Neural Tube Defects / Q000473:pathology* / Q000601:surgery; D012189:Retrospective Studies; D016135:Spinal Dysraphism / Q000473:pathology* / Q000601:surgery