Teres Minor Muscle

Description

Posterior shoulder anatomy is presented with the teres minor isolated in relation to the scapula and proximal humerus in an adult female. Along the lateral border of the scapula, teres minor runs superior to teres major and inferior to infraspinatus, with its tendon coursing laterally to insert on the greater tubercle of the humerus near the posterior aspect of the glenohumeral joint capsule. Superficial to the rotator cuff, the posterior deltoid caps the shoulder laterally, while trapezius occupies a more medial and superior plane over the upper back. Clear fiber direction. Teres minor is the most frequently underappreciated cuff muscle, yet its line of pull makes it a primary external rotator in abduction and a stabilizer against posterior translation of the humeral head. This posterior view helps distinguish teres minor from infraspinatus, a practical point when interpreting cuff MRI for fatty infiltration and tendon tears, where isolated teres minor atrophy can suggest axillary nerve involvement or quadrilateral space syndrome. Surgeons also reference this interval when planning posterior approaches and when mapping safe zones around the surgical neck of the humerus. Ideal for gross anatomy and kinesiology teaching on rotator cuff function, and for orthopedic, sports medicine, and radiology materials discussing external rotation weakness, posterior shoulder pain, and cuff tear patterns in women. It also supports patient-facing education when explaining why targeted strengthening of teres minor differs from general deltoid training. Anatomical accuracy verified by SciePro's Medical Advisory Board.