title: The ability of the Biodex Stability System to distinguish level of function in subjects with a second-degree ankle sprain.
abstract: OBJECTIVE
  To assess the capacity of the Biodex Stability System using a one-leg stance protocol to differentiate between injured and non-injured limbs and between level of disabilities.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  Military and civilian clinic.
  
  
  METHODS
  Thirty-four individuals with a second-degree lateral ankle sprain and 36 healthy subjects.
  
  
  METHODS
  Subjects were tested on the Stability System 30 days after injury using a one-leg stance protocol in the dynamic limit-of-stability mode. All subjects also filled out a disability questionnaire (Lower Extremity Functional Scale). The groups were compared based on the overall dynamic limit-of-stability score and its relationship with the score on the disability questionnaire was also examined.
  
  
  RESULTS
  The overall dynamic limit-of-stability scores (subjects with a lateral ankle sprain: 13.0% (5.5)-26.0% (9.2); healthy subjects: 16.9% (7.9)-27.9% (9.6)) clustered in the lower end of the theoretical range of 0-100%. Statistically significant differences in the overall dynamic limit-of-stability scores were found between the injured and non-injured limbs but group differences were small and clinically not relevant. No significant relationships were found between the overall dynamic limit-of-stability scores and the Lower Extremity Functional Scale scores (58.2 (11.8)) of the subjects with a lateral ankle sprain.
  
  
  CONCLUSIONS
  The one-leg stance protocol carried out in the dynamic limit-of-stability mode is very challenging and offers a very limited capacity to differentiate between injured and non-injured limbs. The main outcome of the Stability System does not appear to be a good indicator of the functional capacity of people with a lateral ankle sprain.
authors.affiliation: Physiotherapy Clinic, Valcartier Garrison, 5th Field Ambulance, Canadian Forces Health Services and Rehabilitation Department, Faculty of Medicine, Laval University, Quebec City, Canada. Perron.mm@forces.gc.ca
authors.forename: Marc
authors.initials: M
authors.lastname: Perron
authors.forename: Luc J
authors.initials: LJ
authors.lastname: Hébert
authors.forename: Bradford J
authors.initials: BJ
authors.lastname: McFadyen
authors.forename: Sylvain
authors.initials: S
authors.lastname: Belzile
authors.forename: Mario
authors.initials: M
authors.lastname: Regniére
mesh_terms: D000328:Adult; D016512:Ankle Injuries / Q000503:physiopathology* / Q000534:rehabilitation; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007866:Leg; D008297:Male; D004856:Postural Balance / Q000502:physiology*; D011187:Posture / Q000502:physiology*; D020127:Recovery of Function / Q000502:physiology; D012046:Rehabilitation / Q000295:instrumentation*; D015203:Reproducibility of Results; D013180:Sprains and Strains / Q000503:physiopathology* / Q000534:rehabilitation