Teres Minor Muscle, Posterior View

Description

Positioned along the lateral border of the scapula, the teres minor is highlighted posteriorly as it runs from the upper two thirds of that border toward the proximal humerus, its tendon blending with the posterior glenohumeral joint capsule to insert on the inferior facet of the greater tubercle. Superior to it sits the infraspinatus, while the teres major lies inferior and more anterior, creating a clear interval along the axillary border. Laterally, the tendon passes deep to the posterior deltoid on its way to the humeral head, close to the inferior aspect of the glenoid cavity and the posterior labrum. This is a small muscle with big consequences. Posterior views like this matter because teres minor is the rotator cuff component most often isolated as a discrete structure during assessment of external rotation strength, particularly with the arm abducted, where its line of pull differs from infraspinatus. At the posterior shoulder, its deep surface helps define the quadrangular space, so an atrophic teres minor on MRI can be a clue to axillary nerve compression or a posterior humeral circumflex artery problem, and the muscle also becomes a key landmark during posterior approaches to the glenohumeral joint. For surgeons planning repair of a posterior cuff tear, the relationship between the tendon footprint on the greater tubercle and the posteroinferior capsule is the operative map. Use this illustration in gross anatomy lab manuals, orthopedic and sports medicine teaching files, and operative technique chapters describing posterior shoulder exposure, rotator cuff pathology, or quadrangular space syndrome, where learners need an unambiguous posterior orientation of tendon, capsule, and bony landmarks. Anatomical accuracy verified by SciePro's Medical Advisory Board.