title: Intrasubject repeatability of gait analysis data in normal and spastic children.
abstract: OBJECTIVE
  To evaluate intrasubject repeatability of data obtained from computer-aided motion analysis in normal and spastic children.
  
  
  METHODS
  Prospective controlled study.
  
  
  BACKGROUND
  Information from gait analysis is used in selecting therapeutic interventions for gait improvement in cerebral palsy. While there are several studies regarding repeatability of normal gait, there are no studies evaluating the repeatability of spastic gait.
  
  
  METHODS
  Forty children (20 normal, 20 with diplegic type of cerebral palsy) were subjected to gait analysis. Kinematic, kinetic and time distance parameters obtained from gait analysis were studied for intrasubject variability within-day and between-day using statistical measures.
  
  
  RESULTS
  Normal children had lower variability in time distance parameters than spastic children both within and between days. The repeatability of kinetics was better than those of kinematics, and values for normal children were better than those for spastic children. Within-day repeatability of kinematics and kinetics was better in normal children. Between-day repeatability of kinematics was better in normal children, while spastic children showed better repeatability for kinetics.
  
  
  CONCLUSIONS
  We found lower repeatability of gait analysis data in spastic children compared to normal children. Restricted joint range of motion due to spasticity in the group of cerebral palsy patients may be responsible for the lower repeatability of data. Some errors due to marker placement are inadvertent and contribute to the lower between-day repeatability.
  
  
  CONCLUSIONS
  The results of this study should be of interest to clinicians who make therapeutic decisions in patients with cerebral palsy using gait analysis data, and for scientists studying normal and pathological gait.
authors.affiliation: Department of Paediatric Orthopaedics, Karl Franzens University of Graz, Auenbruggerplatz 34, A-8036, Graz, Austria. gerhardt.steinwender@kfunigraz.ac.at
authors.forename: G
authors.initials: G
authors.lastname: Steinwender
authors.forename: V
authors.initials: V
authors.lastname: Saraph
authors.forename: S
authors.initials: S
authors.lastname: Scheiber
authors.forename: E B
authors.initials: EB
authors.lastname: Zwick
authors.forename: C
authors.initials: C
authors.lastname: Uitz
authors.forename: K
authors.initials: K
authors.lastname: Hackl
mesh_terms: D000293:Adolescent; D000843:Ankle Joint / Q000502:physiology; D001696:Biomechanical Phenomena; D002547:Cerebral Palsy / Q000150:complications / Q000503:physiopathology*; D002648:Child; D005684:Gait / Q000502:physiology*; D020233:Gait Disorders, Neurologic / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology; D006621:Hip Joint / Q000502:physiology; D006801:Humans; D007719:Knee Joint / Q000502:physiology; D009068:Movement / Q000502:physiology; D011446:Prospective Studies; D016059:Range of Motion, Articular / Q000502:physiology; D015203:Reproducibility of Results; D013997:Time Factors