title: Assessment of upper limb function in young Friedreich ataxia patients compared to control subjects using a new three-dimensional kinematic protocol.
abstract: BACKGROUND
  The assessment of Friedreich ataxia effects on upper limb function in clinical follow-up remains a challenging issue. To complete the usual clinical scales, an upper limb kinematic protocol adapted to Friedreich ataxia children and young adults has been developed and applied to both patients and control subjects.
  
  
  METHODS
  Nineteen Friedreich ataxia patients (7-24 years old) and fifteen healthy controls (9-24) were examined twice during three tasks (drawing, pointing, pro-supination) inspired from the "International Cooperative Ataxia Rating Scale". A custom-made and adjustable device allowed standardized positioning of the subject (in a seated position) and task execution. A three-dimensional kinematic analysis of the whole upper limb was performed using an electromagnetic device. The between session reliability and measurement errors of spatiotemporal and angular kinematic parameters were quantified before the analysis of their discriminative ability between healthy subjects and patients.
  
  
  RESULTS
  Most of the parameters were significantly different between ataxia patients and controls, showing the discriminative ability between these two populations. In particular, the task duration, the drawing and pointing errors were higher for ataxia patients. In most of the cases, the between session reliability was found good to excellent for the spatiotemporal parameters and moderate to excellent for the kinematic parameters.
  
  
  CONCLUSIONS
  Kinematic differences have been pointed out between Friedreich ataxia patients and controls, leading to a better understanding of the effect of this pathology on upper limb function. Discriminative ability and reliability of the developed protocol were demonstrated for many parameters, making it a relevant tool for clinical follow-up.
authors.affiliation: Arts et Métiers ParisTech, Equipe Biomécanique et Remodelage Osseux (EPBRO), 151, Boulevard de l'Hôpital, F-75013, Paris, France. nathalie.maurel@ensam.eu
authors.forename: Nathalie
authors.initials: N
authors.lastname: Maurel
authors.forename: Amadou
authors.initials: A
authors.lastname: Diop
authors.forename: Arnaud
authors.initials: A
authors.lastname: Gouelle
authors.forename: Corinne
authors.initials: C
authors.lastname: Alberti
authors.forename: Isabelle
authors.initials: I
authors.lastname: Husson
mesh_terms: D000203:Activities of Daily Living / Q000145:classification*; D000293:Adolescent; D000328:Adult; D001132:Arm / Q000503:physiopathology*; D001696:Biomechanical Phenomena; D002648:Child; D016002:Discriminant Analysis; D055590:Electromagnetic Phenomena; D005260:Female; D005621:Friedreich Ataxia / Q000145:classification* / Q000503:physiopathology*; D006801:Humans; D008297:Male; D009068:Movement / Q000502:physiology*; D015203:Reproducibility of Results; D055815:Young Adult