title: The relationship of the umbilicus to the aortic bifurcation: implications for laparoscopic technique.
abstract: OBJECTIVE
  We evaluated the location of the umbilicus relative to the aortic bifurcation and the left common iliac vein where it crosses the midline.
  
  
  METHODS
  Abdominal computed tomography images from 35 reproductive-age women were retrospectively reviewed to determine the location of the umbilicus. The results were correlated with body mass index using Pearson correlation coefficient and a two-tailed paired t test.
  
  
  RESULTS
  The location of the umbilicus, but not the aortic bifurcation, was more caudal in heavier women and negatively correlated with body mass index. In nonobese women, the mean location of the umbilicus was 0.4 cm caudal to the aortic bifurcation, and was at or cephalad to the bifurcation in eight of 15 (53%). In overweight women, the mean umbilical location was 2.4 cm caudal to the bifurcation, and in obese women, 2.9 cm caudal to the bifurcation. In the last two groups of subjects, the umbilicus was located at the level of the bifurcation in six of 20 (30%). In every case, the umbilicus was located cephalad to where the common iliac vein crossed the midline.
  
  
  CONCLUSIONS
  The umbilicus is often located at or cephalad to the aortic bifurcation, and consistently located cephalad to where the left common iliac vein crosses the midline. The laparoscopic approach should take these relationships into account to minimize injuries to major retroperitoneal vessels.
authors.affiliation: Department of Obstetrics and Gynecology, University of Michigan Medical Center, Ann Arbor.
authors.forename: W W
authors.initials: WW
authors.lastname: Hurd
authors.forename: R O
authors.initials: RO
authors.lastname: Bude
authors.forename: J O
authors.initials: JO
authors.lastname: DeLancey
authors.forename: M L
authors.initials: ML
authors.lastname: Pearl
mesh_terms: D000328:Adult; D001012:Aorta, Abdominal / Q000033:anatomy & histology*; D015992:Body Mass Index; D005260:Female; D006801:Humans; D010535:Laparoscopy / Q000379:methods; D008875:Middle Aged; D009765:Obesity; D014472:Umbilicus / Q000033:anatomy & histology*