Innermost intercostal muscles

Artery: Intercostal arteries

Nerve: Intercostal nerves

Description:

The innermost intercostal muscle is a layer of intercostal muscles deep to the plane that contains the intercostal nerves and intercostal vessels and the internal intercostal muscles.

It may be divided into:

• transversus thoracis anteriorly
• lateral muscle slips laterally (which cross a single intercostal space)
• subcostalis posteriorly (which often cross more than one intercostal space)