title: The association between Chiari malformation Type I, spinal syrinx, and scoliosis.
abstract: 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.
authors.affiliation: Departments of 1 Neurosurgery and.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Strahle
authors.affiliation: Departments of 1 Neurosurgery and.
authors.forename: Brandon W
authors.initials: BW
authors.lastname: Smith
authors.affiliation: Departments of 1 Neurosurgery and.
authors.forename: Melaine
authors.initials: M
authors.lastname: Martinez
authors.affiliation: 2Radiology, University of Michigan, Ann Arbor, Michigan.
authors.forename: J Rajiv
authors.initials: JR
authors.lastname: Bapuraj
authors.affiliation: Departments of 1 Neurosurgery and.
authors.forename: Karin M
authors.initials: KM
authors.lastname: Muraszko
authors.affiliation: Departments of 1 Neurosurgery and.
authors.forename: Hugh J L
authors.initials: HJ
authors.lastname: Garton
authors.affiliation: Departments of 1 Neurosurgery and.
authors.forename: Cormac O
authors.initials: CO
authors.lastname: Maher
mesh_terms: D000293:Adolescent; D000367:Age Factors; D001139:Arnold-Chiari Malformation / Q000150:complications* / Q000175:diagnosis / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D015897:Comorbidity; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008279:Magnetic Resonance Imaging; D008297:Male; D008499:Medical Records; D016017:Odds Ratio; D012189:Retrospective Studies; D012307:Risk Factors; D012600:Scoliosis / Q000150:complications* / Q000453:epidemiology; D013595:Syringomyelia / Q000150:complications* / Q000175:diagnosis
keywords: CM-I = Chiari malformation Type I; Chiari malformation Type I; OR = odds ratio; scoliosis; spinal syrinx