Median umbilical ligament
The median umbilical ligament (urachal remnant) is a fibrous band in the umbilical region of the abdomen that contains the urachus (embryonic communication between the allantois and cloaca). It runs in the midline, extending from the apex of the urinary bladder to the umbilical ring on the anterior abdominal wall. It supports a raised ridge of parietal peritoneum on the internal aspect of the anterior abdominal wall, known as the median umbilical fold.
The function of the median umbilical ligament, in the postnatal life, is to support the urinary bladder.
This article will discuss the anatomy and function of the median umbilical ligament.
|Definition||Fibrous band that contains the urachal remnant|
|Function||Support to the urinary bladder|
Anatomy and function
The median umbilical ligament is a fibrous band located in the anterior portion of the abdomen, anterior to the urinary bladder. It contains the urachus, which is an embryonic remnant resulting from involution of the allantoic duct that connects the fetal urinary bladder to the umbilicus. This duct becomes progressively obliterated during fetal life. In the postnatal period, it usually completely involutes, becoming part of the median umbilical ligament. In some cases, due to incomplete closure, it may persist as different variants, some regarded as normal, others as pathologic.
The median umbilical ligament extends from the apex of the urinary bladder to the umbilicus. It is located roughly along the midline, between the two medial umbilical ligaments. The parietal peritoneum drapes over the median umbilical ligament, forming a peritoneal ridge known as the median umbilical fold.
Median vs. medial umbilical ligaments
It is important to distinguish between the medial vs. median umbilical ligaments; the medial umbilical ligaments are paired structures related to the umbilical arteries found either side of the median umbilical ligament.
The median and medial umbilical ligaments form a peritoneal depression on each side of the urinary bladder referred to as the supravesical fossae. This area usually contains the fundus of the distended urinary bladder and can be clinically significant owing to the fact that the supravesical hernias can arise here.
As previously mentioned, the main function of the median umbilical ligament in postnatal life is to provide support for the urinary bladder.