title: Comparison of spinal deformity in children with Chiari I malformation with and without syringomyelia: matched cohort study.
abstract: OBJECTIVE
  To describe curve patterns in patients with Chiari malformation I (CIM) without syringomyelia, and compare to patients with Chiari malformation with syringomyelia (CIM + SM).
  
  
  METHODS
  Review of medical records from 2000 to 2013 at a single institution was performed to identify CIM patients with scoliosis. Patients with CIM were matched (1:1) by age and gender to CIM + SM. Radiographic curve patterns, MRI-based craniovertebral junction parameters, and associated neurological signs were compared between the two cohorts.
  
  
  RESULTS
  Eighteen patients with CIM-associated scoliosis in the absence of syringomyelia were identified; 14 (78 %) were female, with mean age of 11.5 ± 4.5 years. Mean tonsillar descent was 9.9 ± 4.1 mm in the CIM group and 9.1 ± 3.0 mm in the CIM + SM group (p = 0.57). Average syrinx diameter in the CIM + SM group was 9.0 ± 2.7 mm. CIM patients demonstrated less severe scoliotic curves (32.1° vs. 46.1°, p = 0.04), despite comparable thoracic kyphosis (43.7° vs. 49.6°, p = 0.85). Two (11 %) patients with CIM demonstrated thoracic apex left deformities compared to 9/18 (50 %) in the CIM + SM cohort (p = 0.01). Neurological abnormalities were only observed in the group with syringomyelia (6/18, or 33 %; p = 0.007).
  
  
  CONCLUSIONS
  In the largest series specifically evaluating CIM and scoliosis, we found that these patients appear to present with fewer atypical curve features, with less severe scoliotic curves, fewer apex left curves, and fewer related neurological abnormalities than CIM + SM. Notably, equivalent thoracic kyphosis was observed in both groups. Future studies are needed to better understand pathogenesis of spinal deformity in CIM with and without SM.
authors.affiliation: Department of Neurosurgery, Barrow Neurological Institute, 350 W. Thomas Road, Phoenix, AZ, 85013, USA. jakub.godzik@bnaneuro.net.
authors.forename: J
authors.initials: J
authors.lastname: Godzik
authors.affiliation: Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA.
authors.forename: A
authors.initials: A
authors.lastname: Dardas
authors.affiliation: Department of Orthopaedic Surgery, Washington University School of Medicine, St. Louis, MO, USA.
authors.forename: M P
authors.initials: MP
authors.lastname: Kelly
authors.affiliation: Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA.
authors.forename: T F
authors.initials: TF
authors.lastname: Holekamp
authors.affiliation: Department of Orthopaedic Surgery, Washington University School of Medicine, St. Louis, MO, USA.
authors.forename: L G
authors.initials: LG
authors.lastname: Lenke
authors.affiliation: Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA.|Department of Pediatric Neurosurgery, St. Louis Children's Hospital, St. Louis, MO, USA.
authors.forename: M D
authors.initials: MD
authors.lastname: Smyth
authors.affiliation: Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA.|Department of Pediatric Neurosurgery, St. Louis Children's Hospital, St. Louis, MO, USA.
authors.forename: T S
authors.initials: TS
authors.lastname: Park
authors.affiliation: Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA.|Department of Pediatric Neurosurgery, St. Louis Children's Hospital, St. Louis, MO, USA.
authors.forename: J R
authors.initials: JR
authors.lastname: Leonard
authors.affiliation: Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA.|Department of Pediatric Neurosurgery, St. Louis Children's Hospital, St. Louis, MO, USA.
authors.forename: D D
authors.initials: DD
authors.lastname: Limbrick
mesh_terms: D000293:Adolescent; D001139:Arnold-Chiari Malformation / Q000150:complications* / Q000175:diagnosis / Q000601:surgery; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D012189:Retrospective Studies; D012600:Scoliosis / Q000175:diagnosis / Q000209:etiology* / Q000601:surgery; D013595:Syringomyelia / Q000150:complications* / Q000175:diagnosis / Q000601:surgery
keywords: Chiari malformation; Kyphosis; Scoliosis; Spinal deformity; Syringomyelia