VH Dissector: Abdominal Wall

Begin with the osseous structures surrounding the abdominal cavity.

Add the Lattisimus dorsi.

Add the Diaphragm.

Add the Transversus abdominis.

Note: The transversus abdominis has a fibrous sheath, known as an aponeurosis, that helps to form the posterior layer of the rectus sheath.

In the suprapubic area, this sheath forms the conjoint tendon.

• Look at the Conjoint tendon which is highlighted in pink. This tendon near the symphsis pubis and can be identified using the Highlight tool.

Add the rectus abdominis and note its tendinous intersections.  These intersections result in individuals with very muscular anterior abdominal walls having '6 pack abs'.

Add the internal oblique.

Note that the contination of the inferior oblique forms the cremasteric fascia. Use the Highlight tool to identify this part of the internal oblique muscle.

Add the external oblique.

The anterior wall of rectus sheath is formed by all three of the aponeuroses (internal oblique, transversus abdominis and external oblique and join at the midline as the linea alba.

Note that the inferior border of the external oblique forms the inguinal ligament.  Find the inguinal ligament using the Highlight tool.

Add the linea alba.

Add a transverse cross-section plane so you can visualize where the viewed cross-section was taken. Use the Highlight tool to identify the components of the abdominal wall musculature in the transverse cross-section window. Use the figure below to help conceptualize how the aponeuroses of these abdominal muscles relate to the rectus abdominis ABOVE the arcuate line.

Now compare the anatomy to that seen from below the arcuate line.  Note that the arcuate line can only be seen from the posterior view of the abdominal wall.  It is located about 1/3 the way down between the umbilicus and the pubic symphysis.

Add the major structures passing under the inguinal ligament. Remember the mnemonic NAVEL? From lateral to medial: Femoral nerve, artery,vein, empty space and lymphatic drainage.

Add the inferior epigastrics and find them on the cadaver.

Add the spermatic cord.

Remember its components:

1. The ductus deferens

2. The artery to the ductus deferens

3. The testicular artery and vein

4. The cremasteric artery and vein

5. The genital branch of the genitofermoral nerve (Innervates the cremasteric muscle)

6. Sympathetic and visceral afferent nerve fibers

7. Lymphatics

8. Remnants of the processus vaginalis

Highlight the internal abdominal oblique muscle.

Remember that the extension of the internal abdominal oblique is the cremaster which forms the deep inguinal ring of the inguinal canal.

Highlight the external abdominal oblique muscle.

Remember that the extension of the external abdominal oblique is the inguinal ligament which forms the superficial ring of the inguinal canal.

Demonstrate the boundaries of The Inguinal Triangle (Hesselbach's Triangle).