title: Subjects with hip osteoarthritis show distinctive patterns of trunk movements during gait-a body-fixed-sensor based analysis.
abstract: BACKGROUND
  Compensatory trunk movements during gait, such as a Duchenne limp, are observed frequently in subjects with osteoarthritis of the hip, yet angular trunk movements are seldom included in clinical gait assessments. Hence, the objective of this study was to quantify compensatory trunk movements during gait in subjects with hip osteoarthritis, outside a gait laboratory, using a body-fixed-sensor based gait analysis. Frontal plane angular movements of the pelvis and thorax and spatiotemporal parameters of persons who showed a Duchenne limp during gait were compared to healthy subjects and persons without a Duchenne limp.
  
  
  METHODS
  A Body-fixed-sensor based gait analysis approach was used. Two body-fixed sensors were positioned at the dorsal side of the pelvis and on the upper thorax. Peak-to-peak frontal plane range of motion (ROM) and spatiotemporal parameters (walking speed, step length and cadence) of persons with a Duchenne limp during gait were compared to healthy subjects and persons without a Duchenne limp. Participants were instructed to walk at a self-selected low, preferred and high speed along a hospital corridor. Generalized estimating equations (GEE) analyses were used to assess group differences between persons with a Duchenne limp, without a Duchenne limp and healthy subjects.
  
  
  RESULTS
  Persons with a Duchenne limp showed a significantly larger thoracic ROM during walking compared to healthy subjects and to persons without a Duchenne limp. In both groups of persons with hip osteoarthritis, pelvic ROM was lower than in healthy subjects. This difference however only reached significance in persons without a Duchenne limp. The ratio of thoracic ROM relative to pelvic ROM revealed distinct differences in trunk movement patterns. Persons with hip osteoarthritis walked at a significantly lower speed compared to healthy subjects. No differences in step length and cadence were found between patients and healthy subjects, after correction for differences in walking speed.
  
  
  CONCLUSIONS
  Distinctive patterns of frontal plane angular trunk movements during gait could be objectively quantified in healthy subjects and in persons with hip osteoarthritis using a body-fixed-sensor based gait analysis approach. Therefore, frontal plane angular trunk movements should be included in clinical gait assessments of persons with hip osteoarthritis.
authors.affiliation: Department of Orthopedics, University Medical Center Groningen, University of Groningen, PO Box 30,001, 9700 RB Groningen, The Netherlands. i.h.f.reininga@umcg.nl
authors.forename: Inge H F
authors.initials: IH
authors.lastname: Reininga
authors.forename: Martin
authors.initials: M
authors.lastname: Stevens
authors.forename: Robert
authors.initials: R
authors.lastname: Wagenmakers
authors.forename: Sjoerd K
authors.initials: SK
authors.lastname: Bulstra
authors.forename: Johan W
authors.initials: JW
authors.lastname: Groothoff
authors.forename: Wiebren
authors.initials: W
authors.lastname: Zijlstra
mesh_terms: D001696:Biomechanical Phenomena / Q000502:physiology*; D005260:Female; D005684:Gait / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D018670:Monitoring, Ambulatory / Q000295:instrumentation*; D009068:Movement / Q000502:physiology; D015207:Osteoarthritis, Hip / Q000503:physiopathology*; D016059:Range of Motion, Articular / Q000502:physiology*