The association between Chiari malformation Type I, spinal syrinx, and scoliosis

J Neurosurg Pediatr. 2015 Jun;15(6):607-11. doi: 10.3171/2014.11.PEDS14135. Epub 2015 Mar 13.


OBJECT Chiari malformation Type I (CM-I) is often found in patients with scoliosis. Most previous reports of CM-I and scoliosis have focused on patients with CM-I and a spinal syrinx. The relationship between CM-I and scoliosis in the absence of a syrinx has never been defined clearly. The authors sought to determine if there is an independent association between CM-I and scoliosis when controlling for syrinx status. METHODS The medical records of 14,118 consecutive patients aged ≤ 18 years who underwent brain or cervical spine MRI at a single institution in an 11-year span were reviewed to identify patients with CM-I, scoliosis, and/or syrinx. The relationship between CM-I and scoliosis was analyzed by using multivariate regression analysis and controlling for age, sex, CM-I status, and syrinx status. RESULTS In this cohort, 509 patients had CM-I, 1740 patients had scoliosis, and 243 patients had a spinal syrinx. The presence of CM-I, the presence of syrinx, older age, and female sex were each significantly associated with scoliosis in the univariate analysis. In the multivariate regression analysis, older age (OR 1.02 [95% CI 1.01-1.03]; p < 0.0001), female sex (OR 1.71 [95% CI 1.54-1.90]; p < 0.0001), and syrinx (OR 9.08 [95% CI 6.82-12.10]; p < 0.0001) were each independently associated with scoliosis. CM-I was not independently associated with scoliosis when controlling for these other variables (OR 0.99 [95% CI 0.79-1.29]; p = 0.9). CONCLUSIONS A syrinx was independently associated with scoliosis in a large pediatric population undergoing MRI. CM-I was not independently associated with scoliosis when controlling for age, sex, and syrinx status. Because CM-I is not independently associated with scoliosis, scoliosis should not necessarily be considered a symptom of low cerebellar tonsil position in patients without a syrinx.

Keywords: CM-I = Chiari malformation Type I; Chiari malformation Type I; OR = odds ratio; scoliosis; spinal syrinx.

MeSH terms

  • Adolescent
  • Age Factors
  • Arnold-Chiari Malformation / complications*
  • Arnold-Chiari Malformation / diagnosis
  • Arnold-Chiari Malformation / epidemiology
  • Child
  • Child, Preschool
  • Comorbidity
  • Female
  • Humans
  • Infant
  • Infant, Newborn
  • Magnetic Resonance Imaging
  • Male
  • Medical Records
  • Odds Ratio
  • Retrospective Studies
  • Risk Factors
  • Scoliosis / complications*
  • Scoliosis / epidemiology
  • Syringomyelia / complications*
  • Syringomyelia / diagnosis