The teres major is an intrinsic muscle of the shoulder region. It forms the inferior border of the quadrangular space, also known as the quadrangular region, which is the area that the axillary nerve and posterior circumflex humeral artery must pass through to reach the posterior scapular region. This muscle plays an important role in the shoulder region, as it aids in the adduction, extension, and medial rotation of the upper limb at the shoulder.
The teres major originates from the posterior surface of the inferior angle of the scapula. From there, it attaches to the medial lip of the intertubercular groove of the humerus.
The primary action of the teres major muscle is to aid in the adduction, extension, and medial rotation of the upper limb at the shoulder.
The teres major muscle is innervated by the lower subscapular nerve, which is a nerve that originates in the brachial plexus, a network of nerves that helps control movement in the upper limbs.
The teres major muscle receives its blood supply from the thoracodorsal artery and the posterior circumflex humeral artery. These two arteries are major branches of the axillary artery and provide oxygenated blood to the teres major to help it function correctly.
The teres major is a powerful intrinsic muscle of the shoulder region that plays an important role in the adduction, extension, and medial rotation of the upper limb at the shoulder. It receives its innervation from the lower subscapular nerve and its blood supply from the thoracodorsal and posterior circumflex humeral arteries. Knowing the anatomy and function of the teres major can help medical professionals better diagnose and treat issues relating to this muscle.
