Rectus and Transversus Abdominis muscle
Rectus Abdominis-- Long, flat strap muscle supports anterior abdominal wall (rectus = straight in Latin) Origin Originates by two tendons or heads Medial head originates from anterior surface of pubic symphysis and anterior pubic ligament Lateral head originates from lateral part of pubic crest Insertion Inserts on horizontal line passing laterally from xiphoid process Intersecting 5th, 6th, and 7th costal cartilages Innervation Ventral primary rami of lower six or seven nerves (T7–T12) Actions Maintains anterior abdominal wall tone during standing Flexion of trunk on pelvis Protects abdominal viscera