ORIGIN:  Conjoint lamellae of thoracolumbar fascia; anterior 2/3 of middle lip of iliac crest; lateral 2/3 of inguinal ligament

 

INSERTION:  Linea alba; costal margin, conjoint tendon

 

ACTION:  Compressor of abdominal wall and supporter of abdominal viscera

 

NERVE:  T7-T12 and L1-2 nerves