title: Lateral trunk lean explains variation in dynamic knee joint load in patients with medial compartment knee osteoarthritis.
abstract: OBJECTIVE
  To test the hypothesis that selected gait kinematics, particularly lateral trunk lean, observed in patients with medial compartment knee osteoarthritis explain variation in dynamic knee joint load.
  
  
  METHODS
  In this cross-sectional observational study, 120 patients with radiographically confirmed varus gonarthrosis underwent three-dimensional gait analysis at their typical walking speed. We used sequential (hierarchical) linear regression to examine the amount of variance in dynamic knee joint load (external knee adduction moment) explained by static lower limb alignment (mechanical axis angle) and gait kinematics determined a priori based on their proposed effect on knee load (walking speed, toe-out angle, and lateral trunk lean angle).
  
  
  RESULTS
  Approximately 50% of the variation in the first peak external knee adduction moment was explained by mechanical axis angle (25%), Western Ontario and McMaster Universities Osteoarthritis Index pain score (1%), gait speed (1%), toe-out angle (12%), and lateral trunk lean angle (13%). There was no confounding or interaction with Kellgren and Lawrence grade of severity.
  
  
  CONCLUSIONS
  Gait kinematics, particularly lateral trunk lean, explain substantial variation in dynamic knee joint load in patients with medial compartment knee osteoarthritis. While largely ignored in previous gait studies, the effect of lateral trunk lean should be considered in future research evaluating risk factors and interventions for progression of knee osteoarthritis.
authors.affiliation: Fowler Kennedy Sport Medicine Clinic, University of Western Ontario, London, Ontario, Canada.
authors.forename: M A
authors.initials: MA
authors.lastname: Hunt
authors.forename: T B
authors.initials: TB
authors.lastname: Birmingham
authors.forename: D
authors.initials: D
authors.lastname: Bryant
authors.forename: I
authors.initials: I
authors.lastname: Jones
authors.forename: J R
authors.initials: JR
authors.lastname: Giffin
authors.forename: T R
authors.initials: TR
authors.lastname: Jenkyn
authors.forename: A A
authors.initials: AA
authors.lastname: Vandervoort
mesh_terms: D000328:Adult; D000368:Aged; D015992:Body Mass Index; D005260:Female; D005684:Gait; D006801:Humans; D007719:Knee Joint / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000503:physiopathology*; D010147:Pain Measurement / Q000379:methods; D012720:Severity of Illness Index; D016138:Walking / Q000502:physiology; D016474:Weight-Bearing