External intercostals
Chest
Deep muscle — it lies under other muscles. X-ray makes the muscles over it see-through.
- Origin
- Lower border of each rib
- Insertion
- Upper border of the rib below
- Action
- Raise the ribs, helping you breathe in
- Nerve supply
- Intercostal nerves (T1–T11)
Eleven thin sheets on each side filling the spaces between the ribs, with fibres running down and forward. They lift the rib cage to help breathing in.
External intercostals anatomy page →