Do youo know what is intercostal?From which is it related?
Intercostal muscles are several groups of muscles that run between the ribs, and help form and move the chest wall. There are three principal layers; the external intercostal muscles, which aid in quiet and forced inhalation. They originate on ribs 1-11 and have their insertion on ribs 2-12. The external intercostals are responsible for the elevation of the ribs, and expanding the transverse dimensions of the thoracic cavity. Located around the ribs the internal intercostal muscles, which aid in forced expiration (quiet expiration is a passive process). They originate on ribs 2-12 and have their insertions on ribs 1-11. The internal intercostals are responsible for the depression of the ribs decreasing the transverse dimensions of the thoracic cavity. the innermost intercostal muscle, the deep layers of the internal intercostal muscles which are separated from the them by the neurovascular bundle. Both the external and internal muscles are innervated by the intercostal nerves (the vent
http://www.yorku.ca/earmstro/journey/intercostals.html The Intercostal Muscles These muscles are found between the ribs, and there are two kinds: the internal and external intercostals. The internal intercostal muscles (in the inside of the ribcase) extend from the front of the ribs, and go around back, past the bend in the ribs. The external intercostal muscles (on the outside of the ribcase) wrap around from the back of the rib almost to the end of the bony part of the rib in front. inside the ribcase The image above is seen from the inside. The yellowish bones are the sternum in the centre and the ribs and clavicle (at the very top). Between the ribs can be seen the internal intercostals. In the front of the ribcase, looking from the bottom of each muscle (i.e., the top of each rib), the muscles go diagonally INWARD. At the bottom of the sternum can be seen the tranversus thoracis muscle which origin
