title: Surgical anatomy and morphologic variations of umbilical structures.
abstract: The umbilicus is the main access route to the abdominal cavity in laparoscopic surgeries. However, its anatomical configuration is rarely studied in the surgical and anatomical literature. With introduction of laparoendoscopic single-site surgery and considering the significant number  of primary and postoperative umbilical hernias, we felt the necessity to comprehensively study the umbilical structures and analyze their protective function against hernias. Twenty-four embalmed cadavers were studied in the anatomy laboratory of Case Western Reserve University. Round hepatic,  median and medial ligaments, umbilical ring, umbilical and umbilicovesicular fasciae, and pattern of attachment to the ring were dissected and measured. Mean age was 82.1 years, ranging between 56 and 96 years, with a male-to-female ratio of 1.4:1. Ninety-two per cent was white and 8 per cent  black adults. According to shape and attachment pattern of ligaments, umbilical ring is classified into five types. Hernia incidence was 25 per cent. All hernia cases lacked the umbilical fascia and the round hepatic ligament was not attached to the inferior border of the ring. The umbilical  ring and its morphologic relation with adjacent ligaments are described and classified into five types. In contrary to sparse existing literature, we propose that umbilical fascia is continuation and condensation of umbilicovesicular rather than transversalis fascia. It was absent in cadavers  forming conjoined median and medial ligaments with a single insertion site to the ring. Round ligament insertion to the inferior border of the ring provides another protective factor. These two protective measures were absent in all the observed umbilical hernias.
authors.affiliation: Department of General Surgery, Case Western Reserve University and Case Medical Center, Cleveland, Ohio 44106, USA.
authors.forename: Amir H
authors.initials: AH
authors.lastname: Fathi
authors.forename: Hooman
authors.initials: H
authors.lastname: Soltanian
authors.forename: Alan A
authors.initials: AA
authors.lastname: Saber
mesh_terms: D034861:Abdominal Wall / Q000033:anatomy & histology / Q000601:surgery; D000368:Aged; D000369:Aged, 80 and over; D000718:Anatomy, Regional / Q000379:methods*; D002102:Cadaver; D005260:Female; D013502:General Surgery / Q000193:education*; D006554:Hernia, Umbilical / Q000601:surgery*; D059685:Herniorrhaphy / Q000193:education* / Q000379:methods; D006801:Humans; D008297:Male; D008875:Middle Aged; D014472:Umbilicus / Q000033:anatomy & histology* / Q000601:surgery*