External Intercostal Muscles

Author: Scott A. Sheffield MS

Last update:

The external intercostal muscles are the most superficial muscles of the rib cage and aid in respiration by elevating the ribs during inhalation.

image descriptionExternal Intercostal Muscles:

An image showing some muscles attached to the skeleton (Sternocleidomastoid, Scalene muscles, Pectoralis major, Serratus anterior, External oblique)
An image showing some muscles attached to the skeleton (Sternocleidomastoid, Scalene muscles, Internal intercostal, Serratus anterior, External oblique)
An image showing the External Intercostal Muscles (highlighted) attached to the skeleton along with other muscles (Sternocleidomastoid, Scalene muscles, Internal intercostal)
An image showing the External Intercostal Muscles attached to the skeleton
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Attachments of External Intercostal: Origin & Insertion

Origin: (proximal attachments)
Inferior border of ribs above.

Insertion: (distal attachments)
Superior border of ribs below.

 

Actions of External Intercostal:

image descriptionElevation of the ribcage during inhalation.

Learn more about the respiratory system with these quizzes and labeled diagrams.

Innervation of External Intercostal:

Intercostal nerves.

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