Muscles Comprising Rotator Cuff
| Muscle | Origin on scapula | Attachment on humerus | Function | Innervation |
| Supraspinatus muscle | supraspinous fossa | superior and middle facet of the greater tuberosity | abducts the arm | Suprascapular nerve (C5) |
| Infraspinatus muscle | infraspinous fossa | posterior facet of the greater tuberosity | externally rotates the arm | Suprascapular nerve (C5-C6) |
| Teres minor muscle | middle half of lateral border | inferior facet of the greater tuberosity | externally rotates the arm | Axillary nerve (C5) |
| Subscapularis muscle | subscapular fossa | lesser tuberosity (60%) or humeral neck (40%) | internally rotates the humerus | Upper and Lower subscapular nerve (C5-C6) |
The supraspinatus muscle fans out in a horizontal band to insert on the superior and middle facets of the greater tubercle. The greater tubercle projects as the most lateral structure of the humeral head. Medial to this, in turn, is the lesser tuberosity of the humeral head. The subscapularis muscle origin is divided from the remainder of the rotator cuff origins as it is deep to the scapula.
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