Teres Minor Muscle, Lateral View

Description

Shown from the left lateral aspect of an adult male, the teres minor appears as a narrow, strap-like rotator cuff muscle arising from the middle portion of the lateral (axillary) border of the scapula and coursing laterally toward the proximal humerus. Its tendon inserts on the inferior facet of the greater tubercle, immediately posterior to the supraspinatus insertion and superior to teres major, placing it deep to the posterior deltoid and posterior to the glenohumeral joint line. Adjacent bony landmarks include the scapular spine and acromion superiorly, the glenoid cavity laterally, and the humeral head and surgical neck anterior to the muscle belly. For teaching shoulder mechanics, this lateral perspective clarifies why teres minor functions as both an external rotator and a dynamic stabilizer, compressing the humeral head into the glenoid during abduction and overhead activity. Small but specific. Clinically, isolated teres minor atrophy is a classic clue in quadrilateral space syndrome, where the axillary nerve and posterior circumflex humeral artery can be compressed between teres minor superiorly, teres major inferiorly, the long head of triceps medially, and the surgical neck of the humerus laterally. The view also supports discussion of posterior shoulder pain patterns and how rotator cuff tears involving the infraspinatus may spare teres minor, altering external rotation strength testing. Use this illustration in gross anatomy and kinesiology modules covering the scapulohumeral rhythm, rotator cuff insertions on the greater tubercle, and relationships deep to the deltoid. It also fits operative anatomy content for posterior approaches to the shoulder and for radiology teaching that pairs muscular atrophy patterns with MRI and ultrasound of the rotator cuff. Anatomical accuracy verified by SciePro's Medical Advisory Board.