title: The capacity to adapt to changing balance threats: a comparison of children with cerebral palsy and typically developing children.
abstract: OBJECTIVE
  This study investigated differences in reactive balance abilities of typically developing children and those with spastic diplegia. Recovery from balance threats was compared by: (i) Platform velocity and amplitude thresholds: Speed and size of platform movement at which children required assistance to remain upright, (ii) percentage of trials with feet-in-place vs. loss of balance, and (iii) center of pressure measures. Participants included 8 children with spastic diplegic cerebral palsy, 15 developmentally matched children (similar walking stages) and 21 age-matched control children.
  
  
  METHODS
  Backward platform movements graded as easy, moderate and difficult were unexpectedly imposed on children standing on a moveable platform.
  
  
  RESULTS
  Children with cerebral palsy (CP) had lower platform velocity thresholds, greater percentages of loss of balance trials, increased distances and increased frequency of directional changes in center-of-pressure (COP) trajectories than control children. Older children with CP fell more often than those under 5 years. Greatest differences between children with and without CP were found in comparisons based on age rather than developmental levels.
  
  
  CONCLUSIONS
  Using balance perturbations that challenged children with CP to the limits of their balance abilities effectively identified age performance differences and differences compared to typically developing children. Implications for rehabilitation programs are presented.
authors.affiliation: Occupational Therapy Graduate Program Department of Pediatrics, University of New Mexico, USA.
authors.forename: P A
authors.initials: PA
authors.lastname: Burtner
authors.forename: M H
authors.initials: MH
authors.lastname: Woollacott
authors.forename: G L
authors.initials: GL
authors.lastname: Craft
authors.forename: M N
authors.initials: MN
authors.lastname: Roncesvalles
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology*; D000367:Age Factors; D016022:Case-Control Studies; D002547:Cerebral Palsy / Q000503:physiopathology*; D002648:Child; D002652:Child Behavior; D002657:Child Development / Q000502:physiology*; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D009048:Motor Skills / Q000502:physiology; D009068:Movement / Q000502:physiology; D004856:Postural Balance / Q000502:physiology*; D011187:Posture / Q000502:physiology; D011312:Pressure; D016138:Walking / Q000502:physiology