Trunk (thorax, abdomen, back)
Anterior Leaf of the Rectus Sheath
Vagina musculi recti abdominis, lamina anterior
- Origin
- Formed by the aponeurosis of the external oblique abdominis muscle and the anterior layer of the split aponeurosis of the internal oblique abdominis muscle
- Insertion
- Fuses at the midline with the anterior leaf of the opposite side at the linea alba
- Function
- Envelops the anterior surface of the rectus abdominis muscle and transmits the pulling forces of the flat abdominal muscles onto the linea alba
- Innervation
- No independent motor innervation; sensory via the anterior cutaneous branches of the thoracoabdominal nerves
- Movement & chain
- Transmits tensile forces of external and internal obliques to the midline linea alba in trunk rotation and flexion.
- Palpation
- Directly palpable beneath subcutaneous fat across the anterior abdominal wall over the rectus abdominis muscle.
- Clinical
- Site of ventral abdominal hernias (epigastric, umbilical) and rectus diastasis; major layer closed during median and paramedian laparotomies.
- Segmental innervation
- T7–T12 (intercostal nerves)
- In clinical practice
- Wound management post-laparotomy/chest drain and abdominal wall monitoring; support incision site during coughing to prevent wound dehiscence.
- Region in the model
- Trunk (thorax, abdomen, back)