title: Force measurements of postural sway and rapid arm lift in seated children with and without MMC.
abstract: OBJECTIVE
  The aim was to investigate the horizontal ground reaction forces of seated postural sway and rapid arm lift in children with and without myelomeningocele. BACKGROUND; It is unclear whether children with myelomeningocele have limited control of body posture entirely caused by the impairment in the legs or also by other dysfunction.
  
  
  METHODS
  11 children with myelomeningocele, 10-13 years, and 20 children without physical impairment were investigated. Data were collected by force plate measurements during quiet sitting and during rapid arm lift. The forces were expressed as the corresponding acceleration of the centre of mass. The amplitude and the frequency of the centre of mass acceleration quantified the sway. Movement time, onset and anteroposterior peak acceleration were analysed during arm lift.
  
  
  RESULTS
  The children with myelomeningocele had a low sway frequency under both conditions: eyes open and eyes closed. The movement time was longer for these children compared to the controls. The onset of initial anteroposterior centre of mass acceleration preceded the arm lift and was directed forward in both groups. The peak centre of mass acceleration was usually directed backward.
  
  
  CONCLUSIONS
  The control of postural sway was different in children with myelomeningocele compared to children without disabilities and this could not be explained by the cele level. The children with myelomeningocele had a slow motor performance of the seated sway and during arm lift.
  
  
  CONCLUSIONS
  Slow motor performance involves functional limitations in the individual child and is important for the therapy program.
authors.affiliation: Folke Bernadottehemmet, Department of Women's and Children's Health, Section of Paediatrics, Children's Hospital, Uppsala University, Bernadottestigen 4, SE-756 48 Uppsala, Sweden. simone.norrlin@ped.uas.lul.se
authors.forename: Simone
authors.initials: S
authors.lastname: Norrlin
authors.forename: Annica
authors.initials: A
authors.lastname: Karlsson
authors.forename: Gunnar
authors.initials: G
authors.lastname: Ahlsten
authors.forename: Håkan
authors.initials: H
authors.lastname: Lanshammar
authors.forename: Hans C
authors.initials: HC
authors.lastname: Silander
authors.forename: Margareta
authors.initials: M
authors.lastname: Dahl
mesh_terms: D000293:Adolescent; D001132:Arm / Q000502:physiology; D001696:Biomechanical Phenomena; D016022:Case-Control Studies; D002648:Child; D005260:Female; D005684:Gait / Q000502:physiology*; D006801:Humans; D007866:Leg / Q000502:physiology; D008297:Male; D008591:Meningomyelocele / Q000503:physiopathology*; D009068:Movement / Q000502:physiology; D004856:Postural Balance / Q000502:physiology*; D011187:Posture / Q000502:physiology*; D011597:Psychomotor Performance; D011930:Reaction Time; D012016:Reference Values; D012494:Sampling Studies; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric