Abdominal muscles External abdominal oblique muscle Origin: External surface of ribs 5-12 Insertion: Linea alba, pubic tubercle, anterior half of iliac crest Innervation: Lower intercostal nerves (T7-T11), subcostal nerve (T12), Iliohypogastric nerve (L1) Function: Bilateral contraction - Trunk flexion, Compresses abdominal viscera, Expiration Unilateral contraction - Trunk lateral flexion (ipsilateral), Trunk rotation (contralateral) Internal abdominal oblique muscle Origin: Thoracolumbar fasci

External abdominal oblique is a paired muscle located on the lateral sides of the abdominal wall. Along with internal abdominal oblique and transversus abdominis, it comprises the lateral abdominal muscles. In a broader picture, these muscles make up the anterolateral abdominal wall together with two anterior abdominal muscles; the rectus abdominis and pyramidalis. Origin and insertion External abdominal oblique muscle originates from the external surfaces of ribs 5-12. The attaching fibers inte