title: Proprioceptive changes impair balance control in individuals with chronic obstructive pulmonary disease.
abstract: BACKGROUND
  Balance deficits are identified as important risk factors for falling in individuals with chronic obstructive pulmonary disease (COPD). However, the specific use of proprioception, which is of primary importance during balance control, has not been studied in individuals with COPD. The objective was to determine the specific proprioceptive control strategy during postural balance in individuals with COPD and healthy controls, and to assess whether this was related to inspiratory muscle weakness.
  
  
  METHODS
  Center of pressure displacement was determined in 20 individuals with COPD and 20 age/gender-matched controls during upright stance on an unstable support surface without vision. Ankle and back muscle vibration were applied to evaluate the relative contribution of different proprioceptive signals used in postural control.
  
  
  RESULTS
  Individuals with COPD showed an increased anterior-posterior body sway during upright stance (p = 0.037). Compared to controls, individuals with COPD showed an increased posterior body sway during ankle muscle vibration (p = 0.047), decreased anterior body sway during back muscle vibration (p = 0.025), and increased posterior body sway during simultaneous ankle-muscle vibration (p = 0.002). Individuals with COPD with the weakest inspiratory muscles showed the greatest reliance on ankle muscle input when compared to the stronger individuals with COPD (p = 0.037).
  
  
  CONCLUSIONS
  Individuals with COPD, especially those with inspiratory muscle weakness, increased their reliance on ankle muscle proprioceptive signals and decreased their reliance on back muscle proprioceptive signals during balance control, resulting in a decreased postural stability compared to healthy controls. These proprioceptive changes may be due to an impaired postural contribution of the inspiratory muscles to trunk stability. Further research is required to determine whether interventions such as proprioceptive training and inspiratory muscle training improve postural balance and reduce the fall risk in individuals with COPD.
authors.affiliation: Department of Rehabilitation Sciences, University of Leuven, KU Leuven, Leuven, Belgium. Lotte.Janssens@faber.kuleuven.be
authors.forename: Lotte
authors.initials: L
authors.lastname: Janssens
authors.forename: Simon
authors.initials: S
authors.lastname: Brumagne
authors.forename: Alison K
authors.initials: AK
authors.lastname: McConnell
authors.forename: Kurt
authors.initials: K
authors.lastname: Claeys
authors.forename: Madelon
authors.initials: M
authors.lastname: Pijnenburg
authors.forename: Chris
authors.initials: C
authors.lastname: Burtin
authors.forename: Wim
authors.initials: W
authors.lastname: Janssens
authors.forename: Marc
authors.initials: M
authors.lastname: Decramer
authors.forename: Thierry
authors.initials: T
authors.lastname: Troosters
mesh_terms: D000368:Aged; D000843:Ankle Joint / Q000502:physiology; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018908:Muscle Weakness / Q000503:physiopathology*; D018482:Muscle, Skeletal / Q000503:physiopathology*; D011187:Posture / Q000502:physiology*; D011434:Proprioception / Q000502:physiology*; D029424:Pulmonary Disease, Chronic Obstructive / Q000503:physiopathology*; D012132:Respiratory Muscles / Q000503:physiopathology*; D014732:Vibration