title: Visuo-oculomotor deficiency at early-stage idiopathic scoliosis in adolescent girls.
abstract: METHODS
  Cross-sectional study.
  
  
  OBJECTIVE
  To determine whether adolescent idiopathic scoliosis (AIS) at onset is associated with oculomotor dysfunction and whether these oculomotor anomalies are correlated to the amplitude of the spine deformation.
  
  
  BACKGROUND
  AIS is related to abnormalities of postural control. To date, few studies have focused on visuo-oculomotor and vestibulo-ocular functions at early-stage AIS.
  
  
  METHODS
  Fifty-three adolescent girls were diagnosed with AIS (mean age: 11.6 ± 2.1 yr) on clinical and radiological criteria (mean Cobb angle: 14.8° ± 5.0°). Visuo-oculomotor and vestibulo-ocular functions were studied with video-oculography, including saccades, smooth pursuit, caloric test, and pendular rotation, with visual vestibular ocular reflex and vestibulo-ocular reflex sequences. Two patient groups were defined according to the mean Cobb angle: group 1 included 29 patients with a Cobb angle from 5° to 14° and group 2 included 24 patients with a Cobb angle from 15° to 25°.
  
  
  RESULTS
  The group 2 showed different saccade characteristics than group 1: higher latencies for saccade sequences characterized by temporal uncertainty and predictive direction; lower velocity regardless of the type of the saccades. No difference was observed for saccadic accuracy and smooth-pursuit gain. For the visual vestibular ocular reflex, group 2 showed lower total maximal slow-phase velocity than group 1, whereas the vestibulo-ocular reflex (tested in dark) did not differ between groups. No difference was observed concerning the caloric vestibular test.
  
  
  CONCLUSIONS
  Patients with a Cobb angle of 15° or more presented normal vestibulo-ocular responses but altered visuo-oculomotor functions, especially for the saccadic latency and velocity. This could be the result of a dysfunction of oculomotor pathways at cerebellar and/or brainstem level. These central disorders may be incriminated in the development of AIS.
authors: Balance Control & Motor Performance, University of Lorraine, UFR STAPS, Villers-lès-Nancy, France.
authors: Alexis
authors: A
authors: Lion
authors: Thierry
authors: T
authors: Haumont
authors: Gérome C
authors: GC
authors: Gauchard
authors: Sylvette R
authors: SR
authors: Wiener-Vacher
authors: Pierre
authors: P
authors: Lascombes
authors: Philippe P
authors: PP
authors: Perrin
mesh_terms: D000293:Adolescent; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D009802:Oculomotor Nerve / Q000503:physiopathology*; D011597:Psychomotor Performance / Q000502:physiology; D011698:Pursuit, Smooth / Q000502:physiology*; D012027:Reflex, Vestibulo-Ocular / Q000502:physiology*; D012438:Saccades / Q000502:physiology*; D012600:Scoliosis / Q000473:pathology / Q000503:physiopathology*; D013997:Time Factors