Muscles of Inspiration Flashcards
What are the principle muscles of inspiration?
External intercostal muscles and scalene muscle.
Where do the external intercostal muscles run from?
Extend from the tubercles of the rib behind round to the costal cartilages to connect to the neighbouring rib.
Where do the fibres of the intercostal muscles run?
Run forward from above, downward.
How do the external intercostal muscles work?
Pulling force in direction of the intercostal fibres,
Ribs move upwards, their ends, together with the sternum, move forwards.
Action of the external intercostals produce an upward and forward movement of the anterior chest wall.
What do the scalene muscles assist with?
Raising the first and second ribs, and the manubrium.
What are the types of scalene muscles?
Anterior
Middle
Posterior
Where do the anterior scalene muscles arise from?
Anterior tubercles of the transverse process from C3-C6.
Where do the middle scalene muscles arise from?
Posterior tubercles of the transverse processes from C2 to C6
Where do the posterior scalene muscles arise from?
Posterior tubercles of the transverse processes from C4 to C6
