title: Morphometric analysis of abdominal organs and rib cage: Implication for risk of solid organ injuries in children.
abstract: BACKGROUND
  Motor vehicle crashes are the leading cause of injury-related mortality in children, with a higher rate of multiorgan injuries than in adults. This may be related to increased solid organ volume relative to abdominal cavity and decreased protection of an underdeveloped cartilaginous rib cage in young children. To date, these anatomic relationships have not been fully described. Our study used analytic morphomics to obtain precise measures of the pediatric liver, spleen, kidneys, and ribs.
  
  
  METHODS
  This pilot study included 215 trauma patients (aged 0-18 years) with anonymized computed tomography (CT) scans. Liver, spleen, and kidney volumes were modeled using semiautomatic algorithms (MATLAB 2013a, MathWorks Inc., Natick, MA). Thirty-one scans were adequate to model the rib cage. Pearson's r was used to correlate absolute organ volume, fractional organ volume, and organ exposure with age and weight.
  
  
  RESULTS
  Spleen, right and left kidney, and liver volumes increased with age and weight (p < 0.01). Right/left kidney and liver fractional volumes decreased with age (p < 0.01), whereas spleen fractional volume remained relatively constant. Exposed surface area of the liver only significantly decreased with age in the anterior (p < 0.01), right (p < 0.01), and posterior views (p = 0.02).
  
  
  CONCLUSIONS
  With this study, we have demonstrated the ability to model solid organ and rib cage anatomy of children using cross-sectional imaging. In younger children, there may be a decrease in fractional organ volume and increase in liver surface exposure, although analysis of a larger sample size is warranted. In the future, this information may be used to improve the design of safety restraints in motor vehicles.
authors.affiliation: From the Section of Pediatric Surgery, Department of Surgery (C.M.H., J.H., P.F.E.), The University of Michigan Medical School and The C.S. Mott Children's Hospital, Section of Trauma Burn Surgery, Department of Surgery (S.C.W.), International Center for Automotive Medicine (S.A.H., S.C.W., P.F.E.), and The University of Michigan Medical School (M.A.S., R.E.T.), Ann Arbor, Michigan.
authors.forename: Calista M
authors.initials: CM
authors.lastname: Harbaugh
authors.forename: Maksim A
authors.initials: MA
authors.lastname: Shlykov
authors.forename: Ryan E
authors.initials: RE
authors.lastname: Tsuchida
authors.forename: Sven A
authors.initials: SA
authors.lastname: Holcombe
authors.forename: Jake
authors.initials: J
authors.lastname: Hirschl
authors.forename: Stewart C
authors.initials: SC
authors.lastname: Wang
authors.forename: Peter F
authors.initials: PF
authors.lastname: Ehrlich
mesh_terms: D034841:Abdominal Cavity / Q000473:pathology*; D000007:Abdominal Injuries / Q000209:etiology; D000293:Adolescent; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007668:Kidney / Q000473:pathology*; D008099:Liver / Q000473:pathology*; D008297:Male; D009929:Organ Size; D012272:Ribs / Q000473:pathology*; D012307:Risk Factors; D013154:Spleen / Q000473:pathology*; D014057:Tomography, X-Ray Computed