Infraspinatus
The Infraspinatus muscle is one of the four rotator cuff muscles crossing the shoulder joint and is commonly injured. It is the main external rotator of the shoulder joint.
Origin
- Posterior surface of the scapula (below the spine of the scapula).
Insertion
- Greater tuberosity on the humerus.
Actions
- Shoulder abduction External rotation.
Innervation
- Suprascapular nerve.
Daily uses
- Brushing hair.
Example strengthening exercises
- Lateral raise.
- Shoulder external rotation.
Example stretches
- Internal rotation stretch.
- Posterior shoulder stretch.
- Posterior shoulder stretch II.
Related injuries
- Rotator cuff injury.
- Impingement syndrome.
Related muscles
- Supraspinatus.
- Subscapularis.
- Teres minor.
