Internal intercostal muscles

The intercostal muscle internus (Latin for " internal intercostal muscle ") is a running in each intercostal space skeletal muscle of the thorax. The Musculi internal intercostal (plural ) run obliquely dorsocaudal ( back - tail upward, in humans so backward and downward ) from a rib to the next.

The Musculi internal intercostal form the chest wall along with the ribs and the lying about them Musculi external intercostals. The contraction of the musculi internal intercostals lower the ribs and thus narrows the chest, making these muscles exhalation ( expiration) support ( " Hilfsexspirator " ) and are counted to the respiratory muscles.