title: The Average Size and Position of the Umbilicus in Young Men and Women.
abstract: BACKGROUND
  Abdominoplasty was the third most common cosmetic surgical procedure in 2012. The umbilicus is transposed within the abdominal skin flap during this procedure. Few studies address the size and location of the umbilicus with precise measurements as well as those that do report on a heterogeneous population. The goal of our study was to determine the average size and position of the ideal umbilicus by limiting the study to young men and women of normal body habitus.
  
  
  METHODS
  Subjects were recruited in a University of Virginia Institutional Review Board-approved study. Demographics of the subjects were recorded. Each subject's umbilicus was assessed for height, width, and position relative to existing landmarks.
  
  
  RESULTS
  Eighty subjects met the inclusion criteria: 43 women and 37 men. Most of the subjects were white (72.5%). The mean ± SD BMI was 22.4 ± 2.5 kg/m. The mean ± SD height and width of the umbilicus was 2.1 ± 0.6 cm and 2.3 ± 0.7 cm, respectively. The umbilicus was located at a mean ± SD of -0.7 ± 1.3 cm in relation to the iliac crest (crest at zero). There were differences seen in the position between men and women. There were no statistical differences in measurements between the races.
  
  
  CONCLUSIONS
  Our study serves as a guide for umbilical positioning with mean measurements for men and women, and categorized by sex and race.
authors.affiliation: From the *Department of Plastic and Maxillofacial Surgery, and †Departments of Public Health Sciences and Orthopaedic Surgery, University of Virginia Health System, Charlottesville, VA.
authors.forename: Deborah
authors.initials: D
authors.lastname: Yu
authors.forename: Wendy M
authors.initials: WM
authors.lastname: Novicoff
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Gampper
mesh_terms: D061645:Abdominoplasty; D000293:Adolescent; D000328:Adult; D005006:Ethnicity; D005260:Female; D006801:Humans; D008297:Male; D009929:Organ Size; D012016:Reference Values; D012737:Sex Factors; D014472:Umbilicus / Q000033:anatomy & histology* / Q000601:surgery; D014768:Virginia; D055815:Young Adult