title: FUNCTIONAL AND RADIOGRAPHIC COMPARISON OF ANTERIOR AND POSTERIOR INSTRUMENTATION FOR THE CORRECTION OF ADOLESCENT IDIOPATHIC SCOLIOSIS.
abstract: OBJECTIVE
  This was a retrospective study to compare the anterior instrumentation (AI) and posterior instrumentation (PI) results among patients diagnosed with adolescent idiopathic scoliosis (Lenke type I) who were treated surgically.
  
  
  METHODS
  The results from 24 patients aged 11 to 18 years with Lenke type I idiopathic scoliosis who underwent surgery with AI (12 patients) or PI (12 patients) were compared. All the patients were operated by the same surgeon and were followed up for a minimum period of five years. The variables for comparison included: coronal and sagittal correction, distance from apical vertebra to midline, apical vertebral rotation, number of instrumented vertebrae and functional variables (by means of the SRS-22 questionnaire). The data obtained were analyzed using the SAS software, version 9. The two groups were compared using Student's t-test with a significance level of 5% (0.05).
  
  
  RESULTS
  The correction of the curve in the frontal plane was higher in the group of patients with the anterior approach, in the immediate (p=0.031) and late (p=0.043) postoperative periods, as was the apical vertebral rotation during the immediate (p=0.002) and late (p=0.019) evaluations. The number of instrumented vertebrae was 7.69 ± 1.38 in the AI group and 11.38 ± 2.92 in the PI group (p = 0.021). Functional assessment (SRS-22) did not show any significant difference (p > 0.05) between the groups.
  
  
  CONCLUSIONS
  The patients who underwent scoliosis correction with AI presented greater correction in the frontal plane, greater derotation of apical vertebrae and a smaller number of fused vertebrae.
authors.affiliation: Postgraduate Student in the Department of Biomechanics, Medicine and Rehabilitation of the Locomotor Apparatus, Hospital das Clínicas, Ribeirao Preto School of Medicine, USP, Ribeirao Preto, SP, Brazil.
authors.forename: Juliano Silveira
authors.initials: JS
authors.lastname: Vieira
authors.affiliation: Postgraduate Student in the Department of Biomechanics, Medicine and Rehabilitation of the Locomotor Apparatus, Hospital das Clínicas, Ribeirao Preto School of Medicine, USP, Ribeirao Preto, SP, Brazil.
authors.forename: Carlos Fernando Pereira
authors.initials: CF
authors.lastname: da Silva Herrero
authors.affiliation: Postgraduate Student in the Department of Biomechanics, Medicine and Rehabilitation of the Locomotor Apparatus, Hospital das Clínicas, Ribeirao Preto School of Medicine, USP, Ribeirao Preto, SP, Brazil.
authors.forename: Maximiliano Aguiar
authors.initials: MA
authors.lastname: Porto
authors.affiliation: Professor of Orthopedic Surgery and Professor of Neurosurgery, Department of Orthopedic Surgery, University of Virginia Chair of Spinal Deformity Research, King Saud University.
authors.forename: Vincent
authors.initials: V
authors.lastname: Arlet
authors.affiliation: Titular Professor of the Department of Biomechanics, Medicine and Rehabilitation of the Locomotor Apparatus, Hospital das Clínicas, Ribeirao Preto School of Medicine, USP, Ribeirao Preto, SP, Brazil.
authors.forename: Helton Luiz Aparecido
authors.initials: HL
authors.lastname: Defino
keywords: Scoliosis; Spine/abnormalities; Surgical Instruments; Thoracic