Round ligament of liver

The round ligament of the liver (igamentum teres hepatis), is a fibrous remnant of the fetal umbilical vein.

General Description

The round ligament of the liver originates at the free border of the falciform ligament, which attaches to the ventral aspect of the diaphragm and the abdominal wall. It extends cranially toward the liver, running within the falciform ligament, and terminates at the liver’s ventral margin, entering the liver parenchyma at the fissure for the round ligament (fissura ligamenti teretis).

In the fetus, the umbilical vein transports oxygenated blood from the placenta to the liver. After birth, the vessel obliterates and becomes a fibrous cord — the round ligament.

Species-Specific Considerations

• Canine and Feline (Dog and Cat): The round ligament is embedded in a prominent falciform ligament, which contains fat. It is relatively long and easy to identify during surgery, especially in obese animals.

• Equine (Horse): The round ligament is present but less conspicuous. It is found along the free edge of the falciform ligament, which is thin and often underdeveloped or even absent in some adults.

• Ruminants (Cattle, Sheep, Goat): The round ligament is relatively inconspicuous. The falciform ligament is small or rudimentary, making the round ligament difficult to distinguish.

• Porcine (Pig): The round ligament is visible and situated in a modest falciform ligament. Due to the anatomy of the pig’s liver (which lacks a clear lobular pattern), the ligament's location is often used as a landmark in dissection.

Topographical Relationships

• Located on the diaphragmatic (parietal) surface of the liver, usually running toward the left medial or quadrate lobe.

• Associated with the umbilical fissure, which lies between the left and quadrate lobes in most species.

• In the adult, it has no vascular function but serves as a peritoneal landmark.