Subscapularis
Subscapularis is one of the four rotator cuff muscles which cross the shoulder joint. The muscle also acts to hold the head of the humerus in position and prevents it moving forwards. It is shown here with a couple of ribs cut away at the front.
Origin
- Anterior (costal) surface of the scapula.
Insertion
- Lesser tuberosity of the humerus.
Actions
- Internal rotation.
- Adduction.
Innervation
- Upper and lower subscapular nerves.
Daily uses
- Tucking the back of your shirt into your trousers.
Example strengthening exercises
- Diagonal extension.
Example stretches
- External rotation stretch.
Related injuries
- Inflammation of the subscapularis muscle.
- Rotator cuff injuries.
Related muscles
- Supraspinatus.
- Infraspinatus.
- Teres minor.
