Supraspinatus muscle

The supraspinatus (plural supraspinati, from Latin supraspinatus) is a relatively small muscle of the upper arm that runs from the supraspinatous fossa superior of the scapula (shoulder blade) to the greater tubercle of the humerus. It is one of the four rotator cuff muscles and also abducts the arm at the shoulder. The spine of the scapula separates the supraspinatus muscle from the infraspinatus muscle, which originates below the spine.

Origin

The supraspinatus muscle arises from the supraspinous fossa, a shallow depression in the body of the scapular above its spine. The supraspinatus muscle tendon passes laterally beneath the cover of the acromion. Research in 1996 showed that the postero-lateral origin was more lateral than classically described.

Insertion

The supraspinatus tendon is inserted into the most superior facet of the greater tubercle of the humerus.

The distal attachments of the three rotator cuff muscles that insert into the greater tubercle of the humerus can be abbreviated as SIT when viewed from superior to inferior (Supraspinatus, Infraspinatus, and Teres minor).

The acronym SITS regarding the rotator cuff muscles is completed by including the Subscapularis muscle, which unlike the other rotator cuff muscles attaches to the lesser tubercle of the humerus...

Innervation

The supraspinatus muscle is supplied by the suprascapular nerve (C5 and C6), which arises from the superior trunk of the brachial plexus...
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