Name

# Infraspinatus

Pronunciation

(in-fruh-spi-NA-t us)

Origin/Proximal Attachment

Infraspinous fossa of the scapula

Insertion/Distal Attachment

Middle facet of the greater tubercle of the humerus, capsule of the shoulder joint

Action/Relevance

Externally rotates the armStabilizes the glenohumeral joint

Innervation

Suprascapular nerve (C5, 6)

Notes

The Infraspinatus muscle is a lateral rotator of the glenohumeral joint.

It attaches medially to the infraspinous fossa of the scapula and laterally to the greater tubercle of the humerus.