Teres Major - Podcast Version TeachMeAnatomy 0:00 / 0:00 1x 0.25x 0.5x 0.75x 1x 1.25x 1.5x 1.75x 2x The teres major is an intrinsic muscle of the shoulder region. It forms the inferior border of the quadrangular space – the space that the axillary nerve and posterior circumflex humeral artery pass through to reach the posterior scapular region. Attachments: Originates from the posterior surface of the inferior angle of the scapula. It attaches to the medial lip of the intertubercular groove of the humerus. Actions: Adduction, extension and medial rotation of the upper limb at the shoulder. Innervation: Lower subscapular nerve. Blood supply: Thoracodorsal artery, posterior circumflex humeral artery By TeachMeSeries Ltd (2025) Fig 1The deltoid and teres major Pro Feature - 3D Model You've Discovered a Pro Feature Access our 3D Model Library Explore, cut, dissect, annotate and manipulate our 3D models to visualise anatomy in a dynamic, interactive way. Learn More Pro Feature - Dissection Images Prosection of the posterior shoulder region. The axillary nerve and posterior circumflex humeral artery can be seen passing through the quadrangular space Prosection of the posterior shoulder region. The axillary nerve and posterior circumflex humeral artery can be seen passing through the quadrangular space You've Discovered a Pro Feature Access our Dissection Image Library Enhance your understanding with high-resolution dissection images showcasing real-life anatomy. Learn More Rate This Article