Scapular region

Question 1

Serratus anterior

Answer 1

Origin-Lateral parts of the 1st-8th ribs

Insertion-Anterior surface of medial border of scapula

Innervation-Long thoracic nerve

Action/Function-1. Protracts scapula 2. Holds scapula against the thoracic wall3. Superior rotation of the scapula

Question 2

Deltoid

Answer 2

Origin-Lateral third of clavicle, acromion process, and spine of scapula

Insertion-Deltoid tuberosity

Innervation-Axillary nerve

Action/Function-“1. All three simultaneously: abduct the humerus after 150 to the horizontal and stabilize the shoulder

2. Anterior: flexion and medial rotation of the humerus
3. Posterior: extension and lateral rotation of the humerus”

Question 3

Teres major

Answer 3

Origin-Inferior angle of scapula (posterior surface)

Insertion-Medial lip of intertubercular sulcus

Innervation-Lower subscapular nerve

Action/Function-Adducts and medially rotates the humerus

Question 4

Suprasinatus (rotator cuff)

Answer 4

Origin-Supraspinous fossa

Insertion-Superior aspect of greater tubercle

Innervation-Suprascapular nerve

Action/Function-“1. Abduct the arm for the first 15 degrees 2. Tonic contraction stabilizes the glenohumeral joint”

Question 5

Infraspinatus (rotator cuff)

Answer 5

Origin-Infraspinous fossa

Insertion-Middle aspect of greater tubercle

Innervation-Suprascapular nerve

Action-lateral rotation of the humerous

Question 6

Teres minor (rotator cuff)

Answer 6

Origin-Middle part of lateral border of scapula

Insertion-Inferior aspect of greater tubercle

Innervation- Axillary nerve

Action/Function-1. Tonic contraction stabilizes the glenohumeral joint 2. Laterally rotates arm

Question 7

Subscapularis (rotator cuff)

Answer 7

Origin-Subscapular fossa

Insertion-Lesser tubercle

Innervation-Upper and lower subscapular nerves

Action/Function-1. Tonic contraction stabilizes the glenohumeral joint 2. Medially rotates arm