title: Mechanisms underpinning longitudinal increases in the knee adduction moment following arthroscopic partial meniscectomy.
abstract: BACKGROUND
  Knee osteoarthritis is common following arthroscopic partial meniscectomy and a higher external peak knee adduction moment is believed to be a contributor. The peak knee adduction moment has been shown to increase over 2 years (from 3-months post-arthroscopic partial meniscectomy). The aim of this study was to evaluate mechanisms underpinning the increase in peak knee adduction moment over 2 years observed in people 3-months following arthroscopic partial meniscectomy.
  
  
  METHODS
  Sixty-six participants with medial arthroscopic partial meniscectomy were assessed at baseline and again 2 years later. Parameters were evaluated at time of peak knee adduction moment as participants walked barefoot at their self-selected normal and fast pace for both time points.
  
  
  RESULTS
  For normal pace walking, an increase in frontal plane ground reaction force-to-knee lever arm accounted for 30% of the increase in peak knee adduction moment (B=0.806 [95% CI 0.501-1.110], P<0.001). For fast pace walking, an increase in the frontal plane ground reaction force magnitude accounted for 21% of the increase in peak knee adduction moment (B=2.343 [95% CI 1.219-3.468], P<0.001); with an increase in tibia varus angle accounting for a further 15% (B=0.310 [95% CI 0.145-0.474], P<0.001).
  
  
  CONCLUSIONS
  Our data suggest that an increase in lever arm and increase in frontal plane ground reaction force magnitude are contributors to the increased knee adduction moment observed over time in people following arthroscopic partial meniscectomy.
authors.affiliation: Centre for Health, Exercise and Sports Medicine, Department of Physiotherapy, School of Health Sciences, The University of Melbourne, Melbourne, VIC, Australia. Electronic address: halm@unimelb.edu.au.
authors.forename: Michelle
authors.initials: M
authors.lastname: Hall
authors.affiliation: Centre for Health, Exercise and Sports Medicine, Department of Physiotherapy, School of Health Sciences, The University of Melbourne, Melbourne, VIC, Australia. Electronic address: timw@unimelb.edu.au.
authors.forename: Tim V
authors.initials: TV
authors.lastname: Wrigley
authors.affiliation: Centre for Health, Exercise and Sports Medicine, Department of Physiotherapy, School of Health Sciences, The University of Melbourne, Melbourne, VIC, Australia. Electronic address: b.metcalf@unimelb.edu.au.
authors.forename: Ben R
authors.initials: BR
authors.lastname: Metcalf
authors.affiliation: Centre for Health, Exercise and Sports Medicine, Department of Physiotherapy, School of Health Sciences, The University of Melbourne, Melbourne, VIC, Australia. Electronic address: ranash@unimelb.edu.au.
authors.forename: Rana S
authors.initials: RS
authors.lastname: Hinman
authors.affiliation: Centre for Musculoskeletal Research, Griffith Health Institute, Griffith University, Gold Coast Campus, Southport, QLD, Australia; School of Psychology and Exercise Science, Murdoch University, Murdoch, WA, Australia. Electronic address: A.Dempsey@murdoch.edu.au.
authors.forename: Alasdair R
authors.initials: AR
authors.lastname: Dempsey
authors.affiliation: Centre for Musculoskeletal Research, Griffith Health Institute, Griffith University, Gold Coast Campus, Southport, QLD, Australia. Electronic address: p.mills@griffith.edu.au.
authors.forename: Peter M
authors.initials: PM
authors.lastname: Mills
authors.affiliation: Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Melbourne, VIC, Australia. Electronic address: flavia.cicuttini@monash.edu.
authors.forename: Flavia M
authors.initials: FM
authors.lastname: Cicuttini
authors.affiliation: Centre for Musculoskeletal Research, Griffith Health Institute, Griffith University, Gold Coast Campus, Southport, QLD, Australia. Electronic address: david.lloyd@griffith.edu.au.
authors.forename: David G
authors.initials: DG
authors.lastname: Lloyd
authors.affiliation: Centre for Health, Exercise and Sports Medicine, Department of Physiotherapy, School of Health Sciences, The University of Melbourne, Melbourne, VIC, Australia. Electronic address: k.bennell@unimelb.edu.au.
authors.forename: Kim L
authors.initials: KL
authors.lastname: Bennell
mesh_terms: D000328:Adult; D001182:Arthroscopy / Q000379:methods*; D001696:Biomechanical Phenomena; D005260:Female; D005684:Gait; D006801:Humans; D007717:Knee; D007719:Knee Joint / Q000601:surgery; D008137:Longitudinal Studies; D008297:Male; D008592:Menisci, Tibial / Q000601:surgery*; D008875:Middle Aged; D009068:Movement; D020370:Osteoarthritis, Knee; D015203:Reproducibility of Results; D013977:Tibia; D016138:Walking
keywords: Gait; Knee joint load; Mechanism; Meniscectomy