Shoulder and Pectoral Region

Question 1

Pectoralis Major

Answer 1

Innervation: Lateral and Medial Pectoral Nerve
Blood Flow: Thoraco-acromial Artery
Action: Adduction of arm

Question 2

Pectoralis Minor

Answer 2

Innervation: Medial Pectoral Nerve
Blood Flow: Thoraco-acromial Artery
Action: Lowers lateral angle of scapula and protracts scapula

Question 3

Deltoid

Answer 3

Innervation: Axillary Nerve
Blood Flow: Posterior Circumflex Humeral Artery
Action: Raises and rotates arm

Question 4

Serratus Anterior

Answer 4

Innervation: Long Thoracic Nerve
Blood Flow: Lateral Thoracic Artery
Action: Holds scapula against thorax

Question 5

Supraspinatus

Answer 5

Innervation: Suprascapular Nerve
Blood Flow: Suprascapular Artery
Action: Raises arm first 10-15 degrees before the deltoid can function

Question 6

Infraspinatus

Answer 6

Innervation: Suprascapular Nerve
Blood Flow: Suprascapular Artery
Action: Laterally rotates arm

Question 7

Teres Minor

Answer 7

Innervation: Axillary Artery
Blood Flow: Circumflex Scapular Artery
Action: Laterally rotates arm

Question 8

Subscapularis

Answer 8

Innervation: Subscapular Nerve
Blood Flow: Subscapular Artery
Action: Medially rotates arm

Question 9

Teres Major

Answer 9

Innervation: Subscapular Nerve
Blood Flow: Circumflex Scapular Artery
Action: Adducts and medially rotates arm

Question 10

Long Head of Triceps Brachii

Answer 10

Innervation: Radial Nerve
Blood Flow: Deep Brachial Artery
Action: Extends forearm

Question 11

Lateral Head of the Triceps Brachii

Answer 11

Innervation: Radial Nerve
Blood Flow: Deep Brachial Artery
Action: Extends forearm

Question 12

Medial Head of the Triceps Brachii

Answer 12

Innervation: Radial Nerve
Blood Flow: Deep Brachial Artery
Action: Extends forearm

Question 13

What is found in the Quadrangular Space?

Answer 13

Axillary Nerve and Posterior Humeral Circumflex Artery

Question 14

What is found in the Triangular Space?

Answer 14

Circumflex Scapular Artery

Question 15

What is found in the Triangular Interval?

Answer 15

Radial Nerve and Deep Brachial Artery

Question 16

Pectoral Fascia

Answer 16

Covers the pectoralis major

Question 17

Axillary Fascia

Answer 17

Continuation of the pectoral fascia laterally

Question 18

Clavipectoral Fascia

Answer 18

Deep to the pectoralis major and encloses the subclavius muscle and pectorals minor muscle

Question 19

What nerves and arteries run around the superior transverse scapular ligament and what is their relative orientation?

Answer 19

Suprascapular artery and the suprascapular nerve run through the superior transverse scapular ligament, with the suprascapular artery running over it and the supra scapular nerve running under it.

“Army over Navy”

Question 20

What are the three bones of the shoulder?

Answer 20

Clavicle, humerus and scapula

Question 21

What is the most commonly injured of the four rotator cuff muscles?

Answer 21

Supraspinatus

Question 22

Describe arterial blood supply to the shoulder.

Answer 22

Subclavian Artery turns into the Axillary Artery which turns into the Brachial Artery

Question 23

What are the branches of the axillary artery?

Answer 23

Easy way to remember is 1st branch has 1, 2nd has 2 and 3rd has 3.

1st Branch: Superior thoracic artery
2nd Branch: Thoracoacromial trunk (Acromial, Deltoid, Pectoral & Clavicular) & Lateral thoracic arteries
3rd Branch: Subscapular (Circumflex scapular & Thoracodorsal), Anterior & Posterior circumflex humeral arteries

Question 24

What area of the breast is the most common site of breast cancer?

Answer 24

Superior-lateral

Question 25

What is the most likely nerve damaged when a “winged scapula” is observed?

Answer 25

Long Thoracic Nerve

Question 26

What muscles attach to the clavicle?

Answer 26

Superiorly: sternocleidomastoid, trapezius, pectoralis major (superoanterior medial surface), and deltoid muscles.

Inferiorly: subclavius muscle

Question 27

What shoulder injury presents with rubbing and clicking of shoulder on overhead motion where the ball of shoulder rubs against ledge (Acromium) over shoulder.

Answer 27

Impingement Syndrome - inflammation of the tendons of the rotator cuff

Question 28

Define the boundaries of the apex of the axilla.

Answer 28

Bounded by the 1st rib, clavicle, and superior edge of the scapula

Question 29

Define the boundaries of the base of the axilla.

Answer 29

Formed by the concave skin, subcutaneous tissue, and axillary fascia and forms the axillary fossa (armpit)

Question 30

Define the boundaries of the anterior wall of the axilla.

Answer 30

Formed by the pectoralis major and minor along with the pectoral and clavipectoral fasciae

Question 31

Define the boundaries of the posterior wall of the axilla.

Answer 31

Formed primarily by the scapula and the subscapularis muscle

Question 32

Define the boundaries of the medial wall of the axilla.

Answer 32

Formed by the thoracic wall, 1st-4th ribs

Question 33

Define the boundaries of the lateral wall of the axilla.

Answer 33

Formed by the intertubercular groove of the humerus

Question 34

Describe the location of the breast.

Answer 34

Two thirds of it rests on deep pectoral fascia and one third rests on the serratus anterior

Question 35

Areolae

Answer 35

The areola contains numerous sebaceous glands known as areolar glands or glands of Montgomery

Question 36

Nipple

Answer 36

Lactiferous ducts open into the

tips

Question 37

Lobule

Answer 37

Functional unit of the breast tissue which is drained by a single lactiferous duct and is separated from other lobules by suspensory ligaments

Question 38

What are the three main arteries that supply the breast?

Answer 38

Lateral thoracic artery, thoracoacromial arteries and posterior intercostal arteries

Question 39

What is the main venous drainage of the breast?

Answer 39

Axillary Vein

Question 40

Where does most of the lymph in the breast drain?

Answer 40

Axillary lymph nodes