title: Characterization of Compensatory Stepping in People With Multiple Sclerosis.
abstract: OBJECTIVE
  To characterize postural responses to forward and backward external perturbations in people with multiple sclerosis (PwMS), and to relate performance to commonly used clinical outcomes.
  
  
  METHODS
  Cross-sectional study. Postural responses were tested during large stepping and smaller feet-in-place perturbations in forward and backward directions.
  
  
  METHODS
  University research laboratory.
  
  
  METHODS
  PwMS (n=54) and age-matched controls (n=21) (N=75).
  
  
  METHODS
  Not applicable.
  
  
  METHODS
  Center of mass displacement and step latency after external perturbations.
  
  
  RESULTS
  PwMS exhibited larger center of mass displacements and step latencies than control participants in response to stepping perturbations (P=.003 and P=.028, respectively). Stepping deficits were more pronounced during backward stepping and were significantly correlated to increased severity on clinical measures (European Database for Multiple Sclerosis disability score and Timed 25-Foot Walk).
  
  
  CONCLUSIONS
  Compensatory stepping is impaired in PwMS and correlates with clinical disability. Measurement of backward compensatory stepping may be more effective at identifying postural dysfunction in PwMS than forward compensatory steps. Prolonged step latencies, large anticipatory postural adjustments, and multiple compensatory steps are especially altered in PwMS, suggesting possible targets for neurorehabilitation.
authors.affiliation: Veterans Affairs Portland Health Care System, Portland, OR; Department of Neurology, Oregon Health and Science University, Portland, OR. Electronic address: dspeterson8@gmail.com.
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Peterson
authors.affiliation: Landon Center on Aging, University of Kansas Medical Center, Kansas City, KS.
authors.forename: Jessie M
authors.initials: JM
authors.lastname: Huisinga
authors.affiliation: Veterans Affairs Portland Health Care System, Portland, OR; Department of Neurology, Oregon Health and Science University, Portland, OR.
authors.forename: Rebecca I
authors.initials: RI
authors.lastname: Spain
authors.affiliation: Veterans Affairs Portland Health Care System, Portland, OR; Department of Neurology, Oregon Health and Science University, Portland, OR.
authors.forename: Fay B
authors.initials: FB
authors.lastname: Horak
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D004185:Disability Evaluation; D005260:Female; D005684:Gait / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000503:physiopathology*; D004856:Postural Balance / Q000502:physiology*; D011187:Posture; D011930:Reaction Time; D016138:Walking / Q000502:physiology*
keywords: Accidental falls; Multiple sclerosis; Posture; Rehabilitation