The linea alba (LA) is a strong fibrous midline structure of the anterior abdominal wall.
The LA is situated between the two recti abdominis muscles.
The umbilicus is a defect in the linea alba through which fetal umbilical vessels pass before birth.
The linea alba is formed by the union of the aponeuroses of the muscles of the anterior abdominal wall.
The linea alba is attached to the xiphoid process superiorly, and to the pubic symphysis inferiorly.
If is narrow inferiorly where the two recti abdominis muscles are in contact with each other posterior to it,
It broadens superiorly from just inferior to the umbilicus.
It is a white line composed mostly of collagen connective tissue, which has a white appearance.
In muscular individuals, its presence can be seen on the skin, forming the depression between the left and right halves of the abdominal muscles.
The LA stabilizes the anterior abdominal wall, as it balances contractile forces from the muscles attached to it.
An abnormal widening of the linea alba is known as diastasis recti.
The linea alba usually darkens during pregnancy due to hormonal changes, becoming the linea nigra.
A median incision through the linea alba is a common surgical approach for abdominal surgery, as it consists of mostly connective tissue, and does not contain any primary nerves or blood vessels.