AnatoMemory

Muscle

Teres major

"Lat's little helper"

Upper limbMuscular system

High-yield

Not a rotator cuff muscle; forms the lower border of the quadrangular/triangular spaces. Lower subscapular nerve.

Overview

A thick muscle at the inferolateral scapula that assists latissimus dorsi in adduction and medial rotation of the arm.

Reference facts

Origin
Posterior surface of the inferior angle of the scapula
Insertion
Medial lip of the intertubercular groove of the humerus
Action
Adducts and medially rotates the arm
Innervation
Lower subscapular nerve (C5, C6)
Blood supply
Subscapular / circumflex scapular arteries

Frequently asked questions

What does the teres major do?

The teres major adducts and medially rotates the arm.

What nerve innervates the teres major?

The teres major is innervated by the lower subscapular nerve (C5, C6).

Where does the teres major attach?

The teres major originates from the posterior surface of the inferior angle of the scapula and inserts on the medial lip of the intertubercular groove of the humerus.

What is the blood supply of the teres major?

The teres major is supplied by the subscapular / circumflex scapular arteries.