Supraspinatus pain referral zone:                    

Supraspinatus (shoulder and arm pain):
Supraspinatus originates above the spine of the scapula and inserts on the head of the humerus. It is one of the muscles of the rotator cuff, and its principal function is to assist the middle deltoid in abduction of the arm. Trigger points in supraspinatus typically refer pain to the shoulder and arm, and are often found in conjunction with trigger points in levator scapulae and deltoids.

Translation: "Supraspinatus" means "above the spine (of the shoulderblade)." The spine of the shoulderblade is a bony ridge running across the shoulderblade near the top. Supraspinatus is one of the muscles of the rotator cuff, and its main job is to help raise the arm away from the side. Trigger points in this muscle can cause pain in the shoulder and arm, and are often mistaken for bursitis.

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