Unit 3 Second Order + Blood Supply

What is the origin of external intercostal?

Rib above

What is the insertion of external intercostal?

Rib below

What is the innervation of external intercostal?

Intercostal nerves (T1-T11)

What is the action of external intercostal?

Elevates ribs, increasing thoracic volume during inspiration

What is the blood supply of external intercostal?

Posterior intercostal arteries; anterior intercostal branches (internal thoracic artery)

What is the origin of internal intercostal?

Rib above

What is the insertion of internal intercostal?

Rib below

What is the innervation of internal intercostal?

Intercostal nerves (T1-T11)

What is the action of internal intercostal?

Interosseous part: depresses ribs during forced expiration; Interchondral part: elevates ribs

What is the blood supply of internal intercostal?

Anterior and posterior intercostal arteries (from internal thoracic and thoracic aorta)

What is the origin of innermost intercostal?

Rib above

What is the insertion of innermost intercostal?

Rib below

What is the innervation of innermost intercostal?

Intercostal nerves (T1-T11)

What is the action of innermost intercostal?

Assists internal intercostals in depressing ribs

What is the blood supply of innermost intercostal?

Anterior/posterior intercostal arteries, internal thoracic, musculophrenic arteries

What is the origin of subcostal?

Internal surface of lower ribs

What is the insertion of subcostal?

Internal surface of second or third rib below

What is the innervation of subcostal?

Intercostal nerves

What is the action of subcostal?

Depresses ribs aiding forced expiration

What is the blood supply of subcostal?

Posterior intercostal arteries

What is the origin of transversus thoracis?

Posterior surface of lower sternum and xiphoid process

What is the insertion of transversus thoracis?

Internal surfaces of costal cartilages 2-6

What is the innervation of transversus thoracis?

Intercostal nerves (T2-T6)

What is the action of transversus thoracis?

Depresses ribs during expiration

What is the blood supply of transversus thoracis?

Intercostal arteries

What is the origin of diaphragm?

Xiphoid process, costal cartilages of ribs, lumbar vertebrae via crura

What is the insertion of diaphragm?

Central tendon

What is the innervation of diaphragm?

Phrenic nerve (C3-C5)

What is the action of diaphragm?

Contracts to increase vertical thoracic volume during inspiration

What is the bloody supply of diaphragm?

Musculophrenic, superior/inferior phrenic, lower intercostal arteries