title: The effect of walking poles on the knee adduction moment in patients with varus gonarthrosis.
abstract: OBJECTIVE
  (1) Test the hypothesis that walking poles decrease the external knee adduction moment during gait in patients with varus gonarthrosis, and (2) explore potential mechanisms.
  
  
  METHODS
  Thirty-four patients with medial compartment knee osteoarthritis (OA) and varus alignment underwent three dimensional (3D) gait analysis with and without using walking poles. Conditions were randomized and walking speed was maintained ±5% of the self-selected speed of the initial condition. The pole held in the hand of the unaffected side was instrumented with a compression load cell.
  
  
  RESULTS
  Student's t tests for paired samples indicated small but statistically significant increases (P < 0.001) in knee adduction moment (calculated from inverse dynamics) for its first peak, second peak and angular impulse when using the poles; mean increases (95% confidence interval - CI) were 0.17%BW*Ht (0.08, 0.27), 0.17%BW*Ht (0.04, 0.30) and 0.15%BW*Ht*s (0.09, 0.22), respectively. There was a decrease (P = 0.015) in vertical ground reaction force (-0.02 BW (-0.04, -0.01)), yet increase (P < 0.001) in its frontal plane lever arm about the knee (0.30 cm (0.15, 0.44)), at the time of the first peak knee adduction moment. Pole force in the vertical direction was inversely related (r = -0.34, P = 0.05) to the increase in first peak adduction moment.
  
  
  CONCLUSIONS
  Although results are variable among patients, and may be related to individual technique, these overall findings suggest that walking poles do not decrease knee adduction moments, and therefore likely do not decrease medial compartment loads, in patients with varus gonarthrosis. Decreases in knee joint loading should not be used as rationale for walking pole use in these patients.
authors.affiliation: Wolf Orthopaedic Biomechanics Laboratory, Fowler Kennedy Sport Medicine Clinic, University of Western Ontario, Canada.
authors.forename: D J
authors.initials: DJ
authors.lastname: Bechard
authors.forename: T B
authors.initials: TB
authors.lastname: Birmingham
authors.forename: A A
authors.initials: AA
authors.lastname: Zecevic
authors.forename: I C
authors.initials: IC
authors.lastname: Jones
authors.forename: K M
authors.initials: KM
authors.lastname: Leitch
authors.forename: J R
authors.initials: JR
authors.lastname: Giffin
authors.forename: T R
authors.initials: TR
authors.lastname: Jenkyn
mesh_terms: D001696:Biomechanical Phenomena; D002183:Canes; D005260:Female; D005684:Gait; D006801:Humans; D007719:Knee Joint / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000503:physiopathology* / Q000534:rehabilitation; D016059:Range of Motion, Articular / Q000502:physiology*; D016138:Walking / Q000502:physiology*; D016474:Weight-Bearing / Q000502:physiology*