The falciform ligament is a fold of peritoneum, the membrane lining the abdominal cavity and covering most of its organs. It links the liver to the anterior abdominal wall and the diaphragm.
Precise Anatomical Placement
The falciform ligament extends from the umbilicus, or navel, upwards towards the inferior surface of the diaphragm. From these points, it connects to the anterosuperior surface of the liver, stretching obliquely from front to back of the abdomen.
One surface faces forward, contacting the peritoneum behind the right rectus abdominis muscle and the diaphragm. The other lies against the anterior surface of the left lobe of the liver.
It divides the liver into its anatomical right and left lobes on its anterior surface. Its inferior free border contains the ligamentum teres hepatis, also known as the round ligament of the liver. This round ligament is a fibrous remnant of the umbilical vein, which was functional during fetal development.
Composition and Appearance
The falciform ligament is composed of a double layer of peritoneum, closely united together. Its name, derived from Latin, describes its typical sickle-shaped or crescent-shaped form. It generally appears as a broad, thin, and often transparent or semi-transparent structure.
Within its layers, it contains a small, yet variable, amount of fat. It may also contain minor vascular structures, such as the falciform artery, though its presence can vary among individuals. Additionally, small paraumbilical veins and nerves can be found within the ligament.
Its Role in the Body
The primary function of the falciform ligament is to provide structural support to the liver. It anchors the liver to the anterior abdominal wall and the diaphragm, helping to maintain the liver’s position within the abdominal cavity.
From an embryological perspective, the falciform ligament is a remnant of the embryonic ventral mesentery. During fetal development, the umbilical vein courses within this structure, connecting the placenta to the developing liver. In adults, its functional importance is primarily structural, rather than playing a direct physiological role in liver function.
Medical Importance
The falciform ligament holds significance as a surgical landmark, particularly during abdominal procedures such as liver resections. Its presence helps surgeons identify the anatomical division of the liver into its right and left lobes, which is important for planning interventions. This makes it a useful guide in both traditional and minimally invasive surgeries.
The ligament can also influence the spread of certain medical conditions. In cases of ascites, where fluid accumulates in the abdominal cavity, the falciform ligament can become outlined by the fluid, making it visible on imaging studies. It can act as a barrier or conduit for the spread of infections or fluid.
Furthermore, in conditions like portal hypertension, the paraumbilical veins located within the free edge of the falciform ligament can enlarge and become prominent. This sometimes leads to a visible network of engorged veins around the umbilicus, known as caput medusae. While rare, the falciform ligament can also be involved in conditions such as torsion of its fatty appendage, or the formation of abscesses or hematomas.