STRUCTURE AND POSITION

•         Teres Major is a muscle present at the back of the Shoulder Joint.
•         Teres Major is a thick and flattened Muscle. It lies inferior to the Teres Minor Muscle.

ATTACHMENTS 

• Origin : Teres Major arises from the Posterior Surface of the Inferior Angle of the Scapula Bone.
• It runs Superolaterally towards Shoulder Joint, inferior to the Teres Minor.
• Insertion : Teres Major is inserted via a tendon into the Medial Ridge of the Intertubercular Groove of the Humerus.

BLOOD SUPPLY 

Teres Major receives its blood via Thoracodorsal Artery, Circumflex Scapular Artery and Posterior Circumflex Humeral Artery.

NERVE SUPPLY 

Teres Major is innervated by the Lower Subscapular Nerve.

ACTION 

• Teres Major is extends, abducts and medially rotates the Shoulder Joint.
• Teres Major only acts when moving against resistance. Above mentioned movements involve Teres Major only when Shoulder Joint is moving against resistance.