Transversus thoracis (Musculus transversus thoracis)

Layer: Muscles

Educational content only — not medical advice.

Anatomy

A thin sheet on the inner front chest wall from the posterior sternum to the costal cartilages of ribs 2–6; the internal thoracic vessels groove it on their upward course.

Origin & insertion

Lower third of the posterior sternal surface and the xiphoid process.

Action

Pulls the costal cartilages downward assisting forced expiration and shrinking the thoracic volume.

Innervation

Intercostal nerves T2–T6.

Clinical notes

The internal thoracic artery over its surface is the standard cardiac bypass graft (LIMA-to-LAD), and the anterior pleural opening passes just beneath — the beating-heart surgeon’s daily landmark.

Related structures

Educational references

FAQ

What is the role of the Transversus thoracis?

A thin sheet on the inner front chest wall from the posterior sternum to the costal cartilages of ribs 2–6; the internal thoracic vessels groove it on their upward course.

Why is the Transversus thoracis clinically important?

The internal thoracic artery over its surface is the standard cardiac bypass graft (LIMA-to-LAD), and the anterior pleural opening passes just beneath — the beating-heart surgeon’s daily landmark.

Source & license

BodyParts3D, © The Database Center for Life Science licensed under CC Attribution 4.0 International (https://creativecommons.org/licenses/by/4.0/). license details