JODDYS

Although the abdominal wall is continuous, it is helpful for descriptive purposes to subdivide it into: (1) the anterolateral abdominal wall; and (2) the posterior abdominal wall.

The Anterolateral Abdominal Wall

Most of this wall consists of 3 muscular layers, each of which have its fibres running in different directions.

Surface Anatomy of the Anterolateral Abdominal Wall

The umbilicus is the obvious feature.

This puckered scar represents the former site of attachment of the umbilical cord.

In physically fit people, the umbilicus lies at the level of the intervertebral disc between L3 and L4 vertebrae.

This is midway between the xiphoid process and the pubic symphysis.

The linea alba (L. alba, white), is a median fibrous white line or band.

This line divides the anterior abdominal wall into right and left halves.

It lies in the anterior median line and is clearly visible in thin muscular persons.

The linea semilunaris is a curved line or groove (convex laterally) that extends from the 9th costal cartilage to the pubic tubercle.

This indicates the lateral border of the rectus abdominis muscle.

Fascia of the Anterior Abdominal Wall

Superficial Fascia

This superficial fascia consists of one layer that contains a variable amount of fat.

The superficial fascia just above the inguinal ligament can be divided into two layers:

There is a fatty superficial layer (Camper's fascia) containing a variable amount of fat.

There is also a membranous deep layer (Scarpa's fascia) containing fibrous tissue and very little fat.

The superficial vessels and nerves run between these two layers.

The membranous deep layer is continuous with the superficial fascia of the thigh, the fascia lata.

This layer is also continuous with the superficial fascia of the perineum (Colles' fascia) and with that investing the scrotum and penis and the labia majora.

The Deep Fascia

This is a very thin strong layer over the superficial muscles and cannot be easily separated from them.