Musculus obliquus internus abdominis

Origin:
 * thoracolumbar fascia;
 * iliac crest;
 * inguinal ligament.

Insertion:
 * linea alba;
 * three last ribs;
 * the lower edge fuses with the aponeurosis of musculus transversus abdominis and forms the falx inguinalis.

Innervation:
 * nervi intercostales (8.–11.);
 * nervus subcostalis;
 * nervus iliohypogastricus;
 * nervus ilioinguinalis.

Function:
 * bends the spine;
 * changes the tilt of the pelvis;
 * participates in the abdominal press;
 * rotates the spine.

Formations on musculus obliquus externus abdominis:
 * aponeurosis musculi obliqui interni: the tendon into which the muscle passes forward.