title: The effects of pediatric obesity on dynamic joint malalignment during gait.
abstract: BACKGROUND
  There is a greater prevalence of lower extremity malalignment in obese children during static posture; however, there has been less examination of dynamic joint function in this cohort. Therefore, the purpose of this study was to determine kinematic differences that exist between obese and non-obese children that would support previously reported static joint malalignment.
  
  
  METHODS
  Forty children were classified as obese (n=20) or non-obese (n=20). Lower extremity joint kinematics were collected during five walking trials at a self-selected pace. Peak joint displacement and amount of joint motion throughout the gait cycle (calculated as the integrated displacement curve) were analyzed for group differences.
  
  
  RESULTS
  Non-obese children had greater peak knee and hip extension during gait; however, there were no group differences in the integrated sagittal displacement curve. Obese children had greater peak angular displacement and integrals of angular displacement for peak hip adduction, hip internal rotation, and foot abduction (toe-out) than non-obese children. Obese children also had greater peak knee external rotation than non-obese children.
  
  
  CONCLUSIONS
  Non-obese children showed greater range of motion in the sagittal plane, particularly at the hip and knee. Frontal and transverse plane differences suggest that obese children function in a more genu valgum position than non-obese children. Static measures of genu valgum have been previously associated with pediatric obesity; the findings indicate that there are also dynamic implications of said malalignment in obese children. Genu valgum presents increased risk of osteoarthritis for obese children and should be considered when prescribing weight bearing exercise to this cohort.
authors.affiliation: School of Sport and Exercise, Massey University, Wellington, New Zealand. Electronic address: s.p.shultz@massey.ac.nz.
authors.forename: Sarah P
authors.initials: SP
authors.lastname: Shultz
authors.affiliation: Department of Movement and Sports Sciences, Ghent University, Belgium; Faculty of Physical Education and Physiotherapy, Vrije Universiteit, Brussel, Belgium.
authors.forename: Eva
authors.initials: E
authors.lastname: D'Hondt
authors.affiliation: School of Sport and Exercise, Massey University, Wellington, New Zealand.
authors.forename: Philip W
authors.initials: PW
authors.lastname: Fink
authors.affiliation: Department of Movement and Sports Sciences, Ghent University, Belgium.
authors.forename: Matthieu
authors.initials: M
authors.lastname: Lenoir
authors.affiliation: Mater Mothers' Hospital, Mater Research Institute, The University of Queensland, Brisbane, Australia; Griffith Health Institute, Griffith University, Gold Coast, Australia.
authors.forename: Andrew P
authors.initials: AP
authors.lastname: Hills
mesh_terms: D001696:Biomechanical Phenomena; D002648:Child; D015331:Cohort Studies; D005260:Female; D005684:Gait; D006801:Humans; D007596:Joints / Q000503:physiopathology*; D007719:Knee Joint / Q000503:physiopathology; D008297:Male; D009068:Movement; D009765:Obesity / Q000503:physiopathology; D063766:Pediatric Obesity / Q000503:physiopathology*; D011187:Posture; D016059:Range of Motion, Articular; D012399:Rotation; D016138:Walking / Q000502:physiology*; D016474:Weight-Bearing
keywords: Body weight; Child; Locomotion; Orthopedic