title: Spondylolysis and spina bifida occulta in pediatric patients: prevalence study using computed tomography as a screening method.
abstract: OBJECTIVE
  The prevalence of spondylolysis reported from radiograph-based studies has been questioned in recent computed tomography (CT)-based studies in adults; however, no new data are available in pediatric patients. Spina bifida occulta (SBO), which has been associated to spondylolysis, may be increasing its prevalence, according to recent studies in adults in the last decades, but without new data in pediatric patients. We aimed to determine the prevalence of spondylolysis and SBO in pediatric patients using abdomen and pelvis CT as a screening tool.
  
  
  METHODS
  We studied 228 patients 4-15 years old (107 males), who were evaluated with abdomen and pelvis CT scans for reasons not related to the spine. The entire lumbo-sacral spine was evaluated to detect the presence of spondylolysis and SBO. We compared the prevalence of spondylolysis in patients with and without SBO. A logistic regression analysis was performed to determine the effect of age and sex as independent predictors of spondylolysis and SBO.
  
  
  RESULTS
  The prevalence of spondylolysis was 3.5 % (1.1-5.9 %); 2/8 patients presented with olisthesis, both with grade I slip. The prevalence of SBO was 41.2 % (34.8-59.2 %) (94 patients). Spondylolysis was not more frequent in patients with SBO than in patients without SBO. Male sex and decreasing age independently predicted the presence of SBO, but not of spondylolysis.
  
  
  CONCLUSIONS
  We observed a 3.5 % prevalence of spondylolysis and a 41.2 % prevalence of SBO. SBO was significantly more frequent in males and younger patients.
authors: Department of Orthopedic Surgery, School of Medicine, Pontificia Universidad Catolica de Chile, Marcoleta 352, Santiago, Chile. jurrutia@med.puc.cl.
authors: Julio
authors: J
authors: Urrutia
authors: Department of Orthopedic Surgery, School of Medicine, Pontificia Universidad Catolica de Chile, Marcoleta 352, Santiago, Chile.
authors: Jorge
authors: J
authors: Cuellar
authors: Department of Orthopedic Surgery, School of Medicine, Pontificia Universidad Catolica de Chile, Marcoleta 352, Santiago, Chile.
authors: Tomas
authors: T
authors: Zamora
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D016015:Logistic Models; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging; D008297:Male; D008403:Mass Screening; D015995:Prevalence; D012737:Sex Factors; D016136:Spina Bifida Occulta / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000453:epidemiology*; D013169:Spondylolysis / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000453:epidemiology*; D014057:Tomography, X-Ray Computed
keywords: Open vertebral arch; Prevalence study; Spina bifida occulta; Spondylolisthesis; Spondylolysis