Muscles of the Shoulder and Upper Extremity

Question 1

Trapezius

Answer 1

Upper, Middle, Lower
Origin: Occipital Bone, spinous process of T1-12
Insertion: Lateral clavicle, acromion, and spine of scapula
Action: Rotation, retraction, elevation, depression of scapula; extends neck and stabilizes shoulder
Innervation: Accessory nerve CN11

Question 2

Levator Scapulae

Answer 2

Origin: Transverse process of C1-C4
Insertion: Medial border of scapula
Action: Elevates scapula
Innervation: Dorsal scapular nerve

Question 3

Rhomboids

Answer 3

Major and Minor
Origin: Spinous process (Minor C7-T1, Major T2-5)
Insertion: Medial Border of scapula
Action: Retraction of scapula
Innervation: Dorsal scapular nerve

Question 4

Pectoralis Minor

Answer 4

Origin: Ribs 3-5
Insertion: Coracoid process of scapula
Action: Elevates ribs, draws scapula down and medially
Innervation: Medial Pectoral nerve

Question 5

Serratus Anterior

Answer 5

Origin: Upper 8-9 Ribs
Insertion: Medial border of scapula
Action: Protraction of scapula
Innervation: Long thoracic nerve