title: Three-dimensional quantitative analysis of the proximal femur and the pelvis in children and adolescents using an upright biplanar slot-scanning X-ray system.
abstract: BACKGROUND
  The anatomy and biomechanics of the pelvis and lower limbs play a key role in the development of orthopaedic disorders.
  
  
  OBJECTIVE
  This study aimed to establish normal reference standards for the measurement of gender-specific pelvic and femoral parameters in children and adolescents with the EOS 2-D/3-D system.
  
  
  METHODS
  EOS 2-D images of 508 individuals (ages 4-16 years) were obtained as part of routine diagnostics. Patients with lower limb abnormalities were excluded. Pelvic and femoral surface 3-D models were generated and clinical parameters calculated by sterEOS 3-D reconstruction software. Data were evaluated using Spearman correlation, paired-samples and independent-samples t-test and linear regression analysis.
  
  
  RESULTS
  Changes in anatomical parameters were found to correlate with age and gender in 1) femoral mechanical axis length: 27.3-43.7 cm (males), 25.5-41.2 cm (females), 2) femoral head diameter: 29.4-46.1 mm (males), 27.7-41.3 mm (females), 3) femoral offset: 26.8-42.4 mm (males), 25.5-37.9 mm (females) and 4) femoral neck length: 35.1-52.9 mm (males), 32.8-48.1 mm (females). There was no gender-specific correlation for the neck shaft angle with values from 130.4° to 129.3°, for femoral torsion (22.5°-19.4°), for sacral slope (39.0°-44.4°) and for lateral pelvic tilt (5.1 mm-6.2 mm). Sagittal pelvic tilt exhibited no significant correlation with age showing average values of 6.5°.
  
  
  CONCLUSIONS
  The EOS 2-D/3-D system proved to be a valuable method in the evaluation of female and male developmental changes in pelvic and lower limb anatomical parameters, in normal individuals younger than 16 years of age.
authors.affiliation: Department of Orthopaedics, Institute of Musculoskeletal Surgery, Clinical Centre, University of Pécs, 7635, Pécs, Akác u.1, Hungary.
authors.forename: Kinga
authors.initials: K
authors.lastname: Szuper
authors.forename: Ádám Tibor
authors.initials: ÁT
authors.lastname: Schlégl
authors.forename: Eleonóra
authors.initials: E
authors.lastname: Leidecker
authors.forename: Csaba
authors.initials: C
authors.lastname: Vermes
authors.forename: Szabolcs
authors.initials: S
authors.lastname: Somoskeöy
authors.forename: Péter
authors.initials: P
authors.lastname: Than
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D010384:Pelvic Bones / Q000000981:diagnostic imaging*; D011859:Radiography; D015203:Reproducibility of Results; D012737:Sex Factors