innermost intercostal muscle

The Innermost intercostal muscle is a layer of intercostal muscle beneath the intercostal nerves and internal intercostal muscles.These are divided into transversus thoracis anteriorly, lateral muscle slips laterally and subcostalis posteriorly.
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In·ner·most intercostal muscle n. A layer of muscle parallel to the internal intercostal muscle but separated from it by the intercostal vessels and [more]Innermost intercostal muscle - Community and Resources