Anterior Abdominal Wall Muscles

Question 1

External abdominal oblique

Answer 1

O: external surface of 5th and 12th ribs
I: linea alba, pubic tubercle, anterior half of iliac crest
A: compresses and supports abdominal viscera; flexes trunk and rotates trunk
I: seven thoracic and subcostal nerve

Question 2

Internal abdominal oblique

Answer 2

O: thoracolumbar fascia, anterior iliac crest, lateral inguinal crest
I: inferior boarders of 10th and 12th ribs, linea alba and pubis via conjoint tendon
A: compresses and supports abdominal viscera; flexes and rotates the trunk
I: six thoracic and L1

Question 3

Transverse abdominis

Answer 3

O: internal surfaces of 7-12 costal cartilage, thoracolumbar fascia, iliac crest, and inguinal ligament
I: linea alba with aponeurosis of internal oblique, pubic crest and pecten pubis via conjoint tendon
A: compresses and supports abdominal viscera
I: six thoracic and L1

Question 4

Rectus abdominis

Answer 4

O: pubic symphysis and pubic crest
I: xiphoid process and costal cartilage 5-7
A: flexes trunk and compresses abdominal viscera
I: inferior 6 thoracic nerves