ACTION: external rotation of humerus
REFERRAL: upper back, anterior shoulder

COMMENTS: This muscle can also refer pain into the vertebral border of the scapula. This muscle has a large attachment and is fairly thin. Because of this, it is normal for it to be a little tender when compressed against the scapula. The lateral trigger point shown refers pain to the anterior shoulder. In sports this muscle becomes strained because its action of decelerating a throwing motion, or racquet swing. It is one of the 4 rotator cuff muscles.

ROTATOR CUFF MUSCLES: (acronym SITS) Subscapularis, Infraspinatus, Teres minor, Supraspinatus