Transversus thoracis lines the deep internal surface of the anterior thorax. It is the internal thoracic wall homologue of the transversus abdominis and is encountered in internal mammary artery harvest for coronary artery bypass grafting.
| Origin | Posterior surface of the sternum and xiphoid process |
|---|---|
| Insertion | Inner surfaces of costal cartilages 2-6 |
| Nerve Supply | Ventral rami of intercostal nerves T2-T6 |
| Blood Supply | Internal thoracic artery perforators |
| Actions | Depresses the costal cartilages during forced expiration; Reduces the thoracic volume |
|---|
The internal thoracic artery runs between the transversus thoracis and the costal cartilages — its harvest for CABG requires division of the transversus thoracis laterally to expose the artery from within the chest. Transversus thoracis plane blocks target the plane between transversus thoracis and the internal thoracic artery for anterior chest wall analgesia.
Not palpable from outside the chest.
Ultrasound-guided injection into the transversus thoracis plane providing anterior chest wall analgesia for cardiac surgery patients via blockade of the anterior intercostal nerves.
