Internal oblique originates from the anterior and lateral iliac crest, the inguinal ligament, and the thoracolumbar fascia. It inserts on ribs 9 through 12 and the linea alba. If internal oblique is hypertonic on one side, say the left side, it has the potential to pull the left iliac crest and the left lower ribcage toward one another. In addition to shortening the left side of the abdomen, tension in the left internal oblique can compress ribs 9 through 12 on the left side.
Let’s break this down:
Quadratus lumborum sits between the anterior and middle layers, while iliocostalis lumborum sits between the middle and posterior layers. Tension in internal oblique is only one way to cause this particular postural imbalance. It could also be caused by hypertonicity in external oblique, iliopsoas, or latissimus dorsi, to name only a few muscles that effect this area.
Check out this youtube video to see how we release internal oblique with Spontaneous Muscle Release Technique, http://www.youtube.com/watch?v=BlSX3r0x7po ,and join us for the SMRT: Hips, Lower Back, & Abdomen course to learn to quickly and painlessly release and balance all of these muscles, https://efullcircle.com/class-schedule/