title: Cervical spine alignment in the pediatric population: a radiographic normative study of 150 asymptomatic patients.
abstract: OBJECTIVE
  To describe the normal cervical sagittal alignment of the pediatric spine in a normal population and to identify the changes during growth period.
  
  
  METHODS
  We randomly selected in PACS database 150 full-spine standing views. Exclusion criteria were: age >18 years, spinal deformity and any disease affecting the spine (medical charts reviewing). For cervical alignment we measured: OC-angle according to Mc Gregor, C1C7 angle, upper cervical angle, inferior cervical angle and C7 tilt. Spino pelvic parameters were analyzed: T1 tilt, thoracic kyphosis, lumbar lordosis, pelvic incidence, sacral slope and pelvic tilt. We compared two age subgroups (juvenile and adolescent). Differences between age groups and gender were tested using Student's t test. Correlations between sagittal spinal parameters were evaluated using Pearson's test.
  
  
  RESULTS
  Cervical spine shape was correlated to cranio cervical orientation to maintain horizontal gaze (r = 0.60) and to thoracic kyphosis (r = -0.46). Cervical spine alignment was significantly different between the two age groups except for the global C1C7 cervical lordosis, which remained stable. A significant gender difference was found for all the cervical sagittal angles (p < 0.01) whereas no differences were demonstrated for the spino pelvic parameters, except the lumbar lordosis (p = 0.047).
  
  
  CONCLUSIONS
  This study is the first to report the cervical spinal alignment in a normal pediatric Caucasian population. Even though cervical lordosis is the common shape, our results showed variability in cervical sagittal alignment. Cervical spine is a junctional area that adjusts its alignment to the head position and to the underlying spinal alignment.
authors.affiliation: Department of Pediatric Orthopedic Surgery, Hôpital Femme Mère Enfant, Université Claude Bernard Lyon I, Hospices Civils de Lyon, 59, Boulevard Pinel, Bron Cedex, 69677, Lyon, France, kariman.abelin-genevois@chu-lyon.fr.
authors.forename: K
authors.initials: K
authors.lastname: Abelin-Genevois
authors.forename: A
authors.initials: A
authors.lastname: Idjerouidene
authors.forename: P
authors.initials: P
authors.lastname: Roussouly
authors.forename: J M
authors.initials: JM
authors.lastname: Vital
authors.forename: C
authors.initials: C
authors.lastname: Garin
mesh_terms: D000293:Adolescent; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging* / Q000254:growth & development; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007738:Kyphosis / Q000000981:diagnostic imaging; D008141:Lordosis / Q000000981:diagnostic imaging; D008297:Male; D010384:Pelvic Bones / Q000000981:diagnostic imaging; D011859:Radiography; D015203:Reproducibility of Results; D012737:Sex Factors; D013131:Spine / Q000000981:diagnostic imaging