Muscle
External intercostals
Elevate ribs (inspiration)
High-yield
Fibres run "hands in pockets"; elevate ribs in inspiration. Intercostal nerves (T1–T11).
Overview
Eleven pairs of muscles between the ribs whose inferomedial fibres elevate the ribs during inspiration.
Reference facts
- Origin
Inferior border of the rib above
- Insertion
Superior border of the rib below
- Action
Elevate the ribs, increasing the thoracic cavity in inspiration
- Innervation
Intercostal nerves (anterior rami of T1–T11)
- Blood supply
Posterior and anterior intercostal arteries