Arterial vascular anatomy of the umbilicus.

The rare occurrence of umbilical necrosis after performance of a transverse rectus abdominis muscle (TRAM) flap prompted this investigation into the specific arterial anatomy of the umbilicus using multiple anatomic techniques. Sixteen fresh cadavers were studied by using dissection of blue latex-injected specimens, radiography of barium latex-injected specimens, and selective ink injection of individual perforators. It was discovered that the umbilicus receives arterial inflow by means of three distinct deep sources in addition to the subdermal plexus. These deep sources are (1) the right and left deep inferior epigastric arteries that each give off several small branches, and a large ascending branch, which courses between the muscle and the posterior rectus sheath passing directly to the umbilicus; (2) the ligamentum teres hepaticum; and (3) the median umbilical ligament. The clinical implications of this study are that the umbilicus should have robust arterial inflow if only one rectus muscle is removed, such as during a unilateral TRAM flap, because the contralateral side should still provide large direct vessels from the deep inferior epigastric arteries to the umbilicus. During bilateral TRAM elevation, all of the large arterial sources are removed from the umbilical inflow and circulation must depend on small vessels from the ligamentum teres and median umbilical ligament. Care should be taken in this latter clinical situation to preserve these sources of blood flow during umbilical flap creation.