title: CT measured normative cartilage growth in children requiring costochondral grafting.
abstract: OBJECTIVE
  Careful operative timing is required for children undergoing microtia repair using autologous costochondral grafting. This operation is performed as early as age 6 in efforts to treat children before school matriculation while allowing for sufficient rib growth. There remains a paucity of data regarding cartilaginous growth of the ribs and synchondrosis routinely harvested during microtia repair. This study employs CT imaging to generate normative costochondral growth characteristics in children.
  
  
  METHODS
  A population-based study was performed.
  
  
  METHODS
  Tertiary care children's hospital.
  
  
  METHODS
  Chest CTs were reviewed in 360 children ages 3 to 20 years. Measurements included: length of ribs 6, 7, and 8 and the height and width of the synchondrosis between ribs 6 and 7. Growth charts are presented for gender and laterality.
  
  
  RESULTS
  At age 6: ribs 6, 7, and 8 measure 5.96 ± 0.69, 7.79 ± 0.84, and 6.33 ± 1.01 cm, respectively. In adulthood the mean length of ribs 6, 7, and 8 are 8.29 ± 1.00, 11.10 ± 1.19, and 8.95 ± 1.99 cm, respectively. The vertical height of the synchondrosis at years 6 and 20 are 2.42 ± 0.39 and 3.59 ± 0.53 cm, respectively. Ribs 6, 7, and 8 as well as the synchondrosis grow in a nearly linear fashion.
  
  
  CONCLUSIONS
  Cartilaginous growth of ribs 6 to 8 during early childhood is nearly linear. Synchondrosis height approaches adult auricle width at 8 years. Rib size is consistently larger in males and on the left side. These data are useful for the pediatric otolaryngologist and facial plastics and reconstructive surgeon performing microtia surgery.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Medical University of South Carolina, Charleston, South Carolina, USA.
authors.forename: Steven M
authors.initials: SM
authors.lastname: Andreoli
authors.forename: Jared C
authors.initials: JC
authors.lastname: Mills
authors.forename: Lauren A
authors.initials: LA
authors.lastname: Kilpatrick
authors.forename: David R
authors.initials: DR
authors.lastname: White
authors.forename: Krishna G
authors.initials: KG
authors.lastname: Patel
mesh_terms: D000293:Adolescent; D000328:Adult; D002356:Cartilage / Q000000981:diagnostic imaging* / Q000254:growth & development* / Q000601:surgery / Q000637:transplantation; D002648:Child; D002675:Child, Preschool; D000013:Congenital Abnormalities / Q000601:surgery*; D065817:Congenital Microtia; D004423:Ear / Q000002:abnormalities* / Q000601:surgery; D004431:Ear, External / Q000601:surgery; D005260:Female; D006776:Hospitals, Pediatric; D006785:Hospitals, University; D006801:Humans; D008297:Male; D013506:Otologic Surgical Procedures / Q000379:methods; D012016:Reference Values; D012272:Ribs / Q000000981:diagnostic imaging* / Q000254:growth & development* / Q000601:surgery / Q000637:transplantation; D013022:South Carolina; D035441:Thoracic Wall / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed; D014182:Transplantation, Autologous; D016896:Treatment Outcome
keywords: costochondral grafting; growth curve; microtia