[1] It may also be called the intima of the internal intercostal muscles.

[2] It is the deepest muscular layer of the thorax,[3] with muscle fibres running vertically (in parallel with the internal intercostal muscles).

[2] It is present only in the middle of each intercostal space, and often not present higher up the rib cage.

[3][4] The diaphragm is continuous with the innermost intercostal muscle.

This muscle article is a stub.