Artery intercostal arteries | Nerve intercostal nerves | |
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Origin Infero-posterior border of each rib (above) Insertion Supero-posterior border of the rib (below) Actions Through adduction of upper ribs to the lower ribs the muscles narrow intercostal slits and diminish thorax volume, therefore the muscles represent expiratory muscles. Latin musculus intercostalis intimus | ||
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. These are 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)
References
Innermost intercostal muscle Wikipedia(Text) CC BY-SA