title: Changes in proprioceptive weighting during quiet standing in women with early and established knee osteoarthritis compared to healthy controls.
abstract: OBJECTIVE
  Knee osteoarthritis (OA) is highly prevalent in people above the age of 60, and is typically associated with pain, stiffness, muscle weakness and proprioceptive deficits. Muscle-tendon vibration has been used to assess the spatial reweighting of proprioceptive input during standing. The current study aimed to investigate whether weighting of proprioceptive input is altered in patients with early and established knee OA compared to asymptomatic controls.
  
  
  METHODS
  The upright posture of 27 participants with early OA, 26 with established OA, and 27 asymptomatic controls was perturbed by vibrating (frequency: 70Hz and amplitude: approximately 0.5mm) ankle muscles (i.e. tibialis anterior and triceps surae) and knee muscles (vastus medialis). Center of pressure displacements of the participants were recorded using a force plate.
  
  
  RESULTS
  Both patients with early and established OA were more sensitive to triceps surae vibration compared to their healthy peers (P<0.01 for both). No such difference was found for the vibration of tibialis anterior or vastus medialis muscles between patients with knee OA and healthy controls.
  
  
  CONCLUSIONS
  These results suggest that the early stages of knee OA may already lead to reweighting of proprioceptive information, suggesting more reliance on ankle proprioceptive input for postural control.
authors.affiliation: Department of Rehabilitation Sciences, Faculty of Kinesiology and Rehabilitation Sciences, KU Leuven, Belgium. Electronic address: armaghan.mahmoudian@gmail.com.
authors.forename: Armaghan
authors.initials: A
authors.lastname: Mahmoudian
authors.affiliation: MOVE Research Institute Amsterdam, Faculty of Human Movement Sciences, VU University Amsterdam, The Netherlands. Electronic address: j.van.dieen@vu.nl.
authors.forename: Jaap H
authors.initials: JH
authors.lastname: van Dieen
authors.affiliation: Department of Health Care, Artesis University College of Antwerp, Belgium. Electronic address: isabel.baert@uantwerpen.be.
authors.forename: Isabel A C
authors.initials: IA
authors.lastname: Baert
authors.affiliation: Department of Kinesiology, Faculty of Kinesiology and Rehabilitation Sciences, KU Leuven, Belgium. Electronic address: ilse.jonkers@faber.kuleuven.be.
authors.forename: Ilse
authors.initials: I
authors.lastname: Jonkers
authors.affiliation: MOVE Research Institute Amsterdam, Faculty of Human Movement Sciences, VU University Amsterdam, The Netherlands; Department of Orthopedics, First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian, China. Electronic address: s.m.bruijn@gmail.com.
authors.forename: Sjoerd M
authors.initials: SM
authors.lastname: Bruijn
authors.affiliation: Department of Development & Regeneration, Skeletal Biology and Engineering Research Center, KU Leuven, Leuven, Belgium. Electronic address: frank.luyten@uzleuven.be.
authors.forename: Frank P
authors.initials: FP
authors.lastname: Luyten
authors.affiliation: MOVE Research Institute Amsterdam, Faculty of Human Movement Sciences, VU University Amsterdam, The Netherlands. Electronic address: gertfaber.sci@gmail.com.
authors.forename: Gert S
authors.initials: GS
authors.lastname: Faber
authors.affiliation: Department of Rehabilitation Sciences, Faculty of Kinesiology and Rehabilitation Sciences, KU Leuven, Belgium. Electronic address: sabine.verschueren@faber.kuleuven.be.
authors.forename: Sabine M P
authors.initials: SM
authors.lastname: Verschueren
mesh_terms: D000368:Aged; D000842:Ankle / Q000502:physiology; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007717:Knee / Q000502:physiology; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000502:physiology; D020370:Osteoarthritis, Knee / Q000503:physiopathology*; D011187:Posture / Q000502:physiology*; D011434:Proprioception / Q000502:physiology*; D012720:Severity of Illness Index; D014732:Vibration; D016474:Weight-Bearing / Q000502:physiology
keywords: Knee osteoarthritis; Postural control; Proprioception; Vibration