Skeletal muscle of the upper back that originates at the infraspinous fossa of the scapula and inserts at the upper edge of the humerus; when contracted, it extends and rotates the arm laterally.
A muscle of the back originating in the infraspinous fossa of the scapula and inserted in the greater tubercle of the humerus. It adducts and laterally rotates the arm and is controlled by the suprascapular nerve from the brachial plexus.