The abdominal wall is divided into anterolateral and posterior aspect.
Each aspect are made up of fascia and muscle layers.
Anterolateral Abdominal Wall
There is a superficial fascia encasing the abdominal wall, no deep fascia. Otherwise, we would struggle to take a deep breath or finish our meal on a Curry Night Out!
The superficial fascia of the abdomen is formed by a superficial fatty layer of Camper, and a deeper fibrous layer of Scarpa.
The superficial fascia of Camper is continuous with the superficial fascia of the rest of the body.
The fibrous layer of Scarpa blends with the deep fascia of the upper thigh, extends Into the penis and scrotum/labia majors and into the perineum as Colles’ fascia.
Clinical Relevance: Due to the structure of these fascia extension, rupture of the urethral bulb may be followed by extravasation of blood and urine into the scrotum, perineum and penis and then into the lower abdomen deep to the fibrous fascia layers; but NOT extravasation downwards into the lower limb, as fluid is stopped by the attachment of fibrous fascia to the deep fascia of the upper thigh.
The anterolateral aspect has FOUR pairs of muscles:
- External Oblique
- Internal Oblique
- Transversus Abdominis
- Rectus Abdominis
We will learn more about these muscles in Section 2: Anterolateral Abdominal Wall Muscles.