Origin/Proximal Attachment Lower borders of the lower 7 ribs (runs like hands in your pocket) Insertion/Distal Attachment Outer lip of the iliac crest; inguinal ligament; anterior layer of the rectus sheath Action/Relevance Unilateral: Rotates trunk to side opposite of contractionLaterally flexes trunk to same side of contraction Bilateral: Flexes the trunk4. Compresses the abdomen Innervation Intercostal nerves (7th-12th) Iliohypogastric nerves (T12, L1) Ilioinguinal nerves (T12, L1) | 
