Anatomy of the Shoulder

Question 1

What are the greater and lesser tubercles of the humerus?

Answer 1

Greater = lateral
Lesser = medial

Question 2

What is the socket part of the ball and socket joint of the shoulder?

Answer 2

Glenoid cavity

Question 3

What spinal level is the spine of the scapula level with?

Answer 3

T3

Question 4

What spinal level is the inferior angle of the scapula level with?

Answer 4

T7

Question 5

What are the 4 joints of the shoulder? Which is a “false” joint?

Answer 5

• Sternoclavicular
• Acromioclavicular
• Glenohumeral
• Scapulothoracic (false)

Question 6

What is the only bony connection of the UE to the axial skeleton?

Answer 6

Sternoclavicular joint

Question 7

What type of joint is the sternoclavicular joint?

Answer 7

Cartilaginous disc joint

Question 8

What are the four ligaments that surround the sternoclavicular joint?

Answer 8

• Sternoclavicular (ant/post)
• Costoclavicular ligament
• Interclavicular ligaments

Question 9

What are the ligaments that surround the AC joint? (3)

Answer 9

• Acromioclavicular
• Coracoclavicular
• Coracoacromial

Question 10

What are the two components of the coracoclavicular ligament? Which is medial and which is lateral?

Answer 10

Trapezoid (lateral)

Conoid (medial)

Question 11

What is the most mobile joint in the body?

Answer 11

Glenohumeral joint

Question 12

What are the motions of the glenohumeral joint?

Answer 12

• Flexion/extension
• Abduction/adduction
• Medial/lateral rotation

Question 13

Why is the glenohumeral joint relatively unstable?

Answer 13

Only holds about 1/3 of the humerus

Question 14

Where is the glenoid labrum weakest?

Answer 14

Anteriorly and inferiorly

Question 15

What primarily provides stability to the glenohumeral joint: muscles or ligaments?

Answer 15

Muscles

Question 16

What are the three components of the glenohumeral ligament? Is this on the anterior or posterior part of the glenohumeral joint?

Answer 16

Superior
Middle
Inferior

Anterior part

Question 17

What is the ligament that sits just above the glenohumeral ligament?

Answer 17

Coracohumeral ligament

Question 18

What is the ligament that sits on the superior aspect of the glenohumeral joint?

Answer 18

Transverse humeral ligament

Question 19

What is the function of the glenoid labrum?

Answer 19

Deepens the glenoid fossa

Question 20

What is the muscle that sits atop the glenohumeral joint?

Answer 20

Supraspinatus

Question 21

What is the muscle that sits posterior along the glenohumeral joint?

Answer 21

Infraspinatus

Question 22

What is the muscle that sits posteriorly along the glenohumeral joint, but inferior to the infraspinatus?

Answer 22

Teres minor

Question 23

What is the muscles that sits anterior to the glenohumeral fossa?

Answer 23

Subscapularis

Question 24

What are the four muscles that comprise the rotator cuff?

Answer 24

• Supraspinatus
• Infraspinatus
• Teres minor
• Subscapularis

Question 25

What are the spinal levels that comprise the brachial plexus?

Answer 25

C5-T1

Question 26

What is scalenus anticus syndrome?

Answer 26

Compression of the brachial plexus/axillary artery between the scalenes

Question 27

What is the Adson's sign, and what does it assess for?

Answer 27

Adson's sign is the loss of the radial pulse in the arm by rotating head to the ipsilateral side with extended neck following deep inspiration.

Question 28

What is costoclavicular syndrome?

Answer 28

Downward movement of the clavicle against the first rib, with a resultant tendency to shearing of the neurovascular bundle

Question 29

What is the costoclavicular test?

Answer 29

The examiner palpates the radial pulse and then draws the patient's shoulder down and back as the patient lifts their chest in an exaggerated "at attention" posture. A positive test is indicated by an absence or decrease in vigor of the pulse and implies possible costoclavicular syndrome.

Question 30

What is pec minor syndrome?

Answer 30

Pec minor compression of the brachial plexus

Question 31

What is the Wright's test?

Answer 31

Abduction of the arms bilaterally. Loss of radial pulse may indicate pec minor compression of the neurovascular bundle

Question 32

What are the three main bursae of the shoulder?

Answer 32

- Subdeltoid - Subacromial - Subscapularis

Question 33

What is the most common cause of bursitis?

Answer 33

Repetitive use

Question 34

What is the innervation of the serratus anterior? What is significant about this?

Answer 34

Long thoracic nerve (SALT) | Sits superficial to the muscle, and is thus easily damaged

Question 35

Injury to the long thoracic nerve causes what classic physical exam finding? Why?

Answer 35

Winged scapular d/t loss of innervation to the serratus anterior

Question 36

What is the origin and insertion of the lat dorsi?

Answer 36

Spinous process of T6 to sacrum | Medial lip of the the intertubercular groove

Question 37

What is the major muscle of shoulder flexion?

Answer 37

Deltoid

Question 38

What is the major muscle of shoulder extension?

Answer 38

Deltoid

Question 39

What are the muscles that are involved with medial rotation of the shoulder? (4)

Answer 39

*Subscapularis* Teres major Pectoralis major Lat dorsi

Question 40

What are the muscles that are involved with lateral rotation of the shoulder? (2)

Answer 40

Infraspinatus | Teres minor

Question 41

What are the two muscles that are involved in abduction of the shoulder? Which initiates movement, and which carries it into full abduction?

Answer 41

Supraspinatus (initiates) | Deltoid (full abduction)

Question 42

What are the two major muscles that are involved in adduction of the shoulder?

Answer 42

Pec major | Lat dorsi

Question 43

What are the muscles that cause scapular elevation? (3)

Answer 43

Trap Levator scap Rhomboids

Question 44

What are the two major muscles that cause scapular depression?

Answer 44

Pec minor | Trap

Question 45

What is protraction of the scapula?

Answer 45

Sticking out the scapula (like hugging oneself)

Question 46

What is retraction of the scapula?

Answer 46

Bringing the scapula back toward the thoracic cage

Question 47

What is adhesive capsulitis?

Answer 47

Glenohumeral capsule becomes stiff and inflamed, restricting motion

Question 48

What are the classic characteristics of a patient with adhesive capsulitis?

Answer 48

Female greater than 50 y/o, with a h/o DM and rotator cuff injury

Question 49

Which should is usually affected with adhesive capsulitis: the dominant, or the non-dominant?

Answer 49

Non-dominant

Question 50

What happens to postural muscles with strain? Phasic?

Answer 50

``` Postural = tight Phasic = Loose ```