Transversus thoracis
Chest
Deep muscle — it lies under other muscles. X-ray makes the muscles over it see-through.
- Origin
- Back of the lower sternum, the xiphoid process and the adjoining costal cartilages
- Insertion
- Inner surfaces of the costal cartilages of ribs 2 to 6
- Action
- Pulls the costal cartilages down, helping forced breathing out
- Nerve supply
- Intercostal nerves (T2–T6)
A thin fan of muscle on the inside of the front chest wall, behind the breastbone. Below, it is continuous with the transversus abdominis.
Transversus thoracis anatomy page →