Shoulder Anatomy

Question 1

Muscle usually used to test function of axillary nerve

Answer 1

Deltoid

Question 2

Weakness of this muscle results in lateral scapular winging

Answer 2

Trapezius

Question 3

Weakness of this muscle results in medial scapular winging

Answer 3

Serratus anterior

Question 4

Groove between the greater and lesser tuberosity of humerus

Answer 4

Bicipital groove

Question 5

Anatomic neck fractures are at high risk for?

Answer 5

Osteonecrosis

Question 6

Muscles that insert into greater tuberosity

Answer 6

Supraspinatus
Infraspinatus
Teres Minor

Question 7

Muscle that insert into lesser tuberosity

Answer 7

Subscapularis

Question 8

Bone that serves as the only link from the upper extremity and axial skeleton

Answer 8

Clavicle

Question 9

Most commonly fractured bone in the body

Answer 9

Clavicle (particularly middle 1/3)

Question 10

First bone in the body to ossify and last to fuse (early 20s)

Answer 10

Clavicle

Question 11

Most common type of glenohumeral dislocation

Answer 11

Anterior dislocation (>90%)

Question 12

Joint with the most range of motion in the body

Answer 12

Shoulder

Question 13

Muscle weakness elicited in empty can test

Answer 13

Supraspinatus

Question 14

Muscles that originate and insert in coracoid process

Answer 14

Originate: Biceps (short head), coracobrachialis; Insert: Pectoralis minor

Question 15

Muscles that insert in proximal humerus

Answer 15

Pectoralis major
Latissimus Dorsi
Teres major

PLT sandwich
Proximal humerus

Question 16

Innervation of latissimus dorsi

Answer 16

Thoracodorsal nerve

Question 17

Borders of the triangular space of the shoulder

Answer 17

TTT for Triangular Space

Teres minor
Teres major
Triceps (long head)

Question 18

Content of triangular space of shoulder

Answer 18

Circumflex scapular artery

Question 19

Borders of quadrangular space of shoulder

Answer 19

Teres minor
Teres major
Humerus (medial border)
Triceps (long head)

Question 20

Contents of quadrangular space of the shoulder

Answer 20

Axillary nerve
Humeral artery
Posterior circumflex artery

Question 21

Borders of triangular interval of the shoulder

Answer 21

Long head of triceps
Lateral head of triceps
Teres major

Question 22

Contents of triangular interval of shoulder

Answer 22

Radial nerve

Deep brachial artery of arm

Question 23

Rotator cuff muscles

Answer 23

Supraspinatus
Infraspinatus
Teres minor
Subscapularis

Question 24

Muscles supplied by spinal accessory nerve

Answer 24

Trapezius

SCM

Question 25

Composition of brachial plexus

Answer 25

RoTonDa in the CT
Root - Trunk - Division - Cord - Terminal Branches

5 roots (ventral rami of spinal nerves)
3 trunks
3 anterior divisions/3 posterior divisions
3 cords
Terminal branches

Question 26

Nerves of the lateral cord of brachial plexus

Answer 26

Lateral pectoral, lateral root to median nerve

Question 27

Nerves of the medial cord of brachial plexus

Answer 27

medial pectoral

medial root to median nerve

Question 28

Nerves of the posterior cord of the brachial plexus

Answer 28

upper subscapular, thoracodorsal, lower subscapular, axillary

Question 29

Continuation of subclavian artery after the first rib

Answer 29

Axillary artery

Question 30

Boundary when axillary artery becomes brachial artery

Answer 30

Lower border of teres major muscle

Question 31

Branches of axillary artery

Answer 31

I (1 branch), II (2 branches), III (3 branches)

I. Proximal to pectoralis minor: Superior thoracic artery
II. Behind the pectoralis minor: Thoracoacromial, lateral thoracic
III. Distal to pectoralis minor: Subscapular, anterior circumflex humeral, posterior circumflex humeral

Question 32

Compression of neurovascular structure (artery, vein, brachial plexus) in the neck by the first rib and scalene muscles

Answer 32

Thoracic outlet syndrome

Question 33

Small (hypoplastic), undescended scapula; omovertebral bone connects C-spine (spinous process) to scapula

Answer 33

Sprengel’s deformity

Question 34

Injury caused by violent stretch between the hand and shoulder (adduction traction of the arm and hyperextension of the neck)

Answer 34

Erb-Duchenne Palsy

Question 35

Clinical signs of Erb-Duchenne palsy

Answer 35

Pronated and medially rotated arm - waiter’s tip hand, due to weakness of biceps brachii (supinator) and infaspinatus (lateral rotator of arm)

can also involve ipsilateral paralysis of diaphragm

Question 36

Injury caused by sudden upward pull of the arm, injury C8 and T1

Answer 36

Klumpke palsy

Question 37

Innervation of the rotator cuff muscles

Answer 37

Supraspinatus - suprascapular n
Infraspinatus - suprascapular n
Teres minor - axillary n
Subscapularis - subscapular n

Question 38

Cortical depression in the posterolateral head of the humerus, resulting from forceful impaction of the humeral head against the anteroinferior glenoid rim when the shoulder is dislocated anteriorly

Answer 38

Hill-Sachs lesion

Question 39

Grading of shoulder separation in acromioclavicular subluxation

Answer 39

Grade 1 - no torn ligament (minor sprain)
Grade 2 - torn acromioclavicular ligament
Grade 3 - torn coracoclavicular and acromioclavicular ligament

Question 40

Joint at which actions of pronation and supination of the forearm occur

Answer 40

Radioulnar joint

Question 41

Avulsion of the medial epicondyle by violent or multiple contractions of the flexor forearm muscles (e.g. strenuous or repeated throwing of a ball)

Answer 41

Little leaguer’s elbow

Question 42

Nerve involved in Saturday night palsy

Answer 42

Radial nerve

Question 43

Syndrome patients with cervical rib are at risk of, especially if they have hyperextension-flexion or whiplash injury

Answer 43

Thoracic outlet syndrome