Shoulder

Question 1

Movements of the scapula

Answer 1

Elevation, depression, abduction, adduction, lateral rotation, medial rotation

Question 2

Answer 2

Sternoclavicular joint

• Articular disc divides into two synovial cavities—allows flat joint to act like a ball-and-socket joint

Question 3

Answer 3

Acromioclavicular joint

• Allows for axial rotation and anteroposterior movement

Question 4

Answer 4

Glenohumoral joint

• Highly mobile, shallow ball-and-socket joint
• Flexion/extension, abduction/adduction, medial+lateral rotation, circumduction

Question 5

Answer 5

Scapulothroacic “joint”

• Allows for elevation/depression, protraction/retraction, rotation

Question 6

Answer 6

Subclavius muscle

• Innervated by nerve to subclavius
• Depression

Question 7

Answer 7

Pectoralis minor

• Innervated by medial pectoral nerve
• Depresses scapula, elevates rib

Question 8

Answer 8

Serratus anterior

• Innervated by long thoracic nerve
• Abducts scapula, elevates ribs

Question 9

Answer 9

Trapezius

• Innervated by accesory nerve (CN XI)
• Superior: elevates scapula, upward rotation of scapula
• Middle: retracts scapula
• Inferior: depresses scapula, upward rotation of scapula

Question 10

Answer 10

Rhomboid major and minor

• Innervated by dorsal scapular nerve
• Adducts scapula, downward rotation of scapula, fix scapula to thoracic wall

Question 11

Answer 11

Levator scapulae

• Innervated by dorsal scapular nerve and cervical (C3, C4) nerves
• Elevates scapula, rotates glenoid cavity inferiorly by rotating scapula

Question 12

Ligaments stabalizing glenohumoral joint

Answer 12

Superior, middle, and inferior glenohumeral ligaments

Question 13

Rotator cuff muscles that stabalize glenohumoral joint

Answer 13

Supraspinatus, infraspinatus, teres minor, and subscapularis

Supraspinatus holds head of humerous in the glenoid cavity

Question 14

Danger of glenohumoral dislocation

Answer 14

Disruption of quadrangular space and risk of injuring the axillary nerve and posterior circumflex humeral vessels

Question 15

Test for spinal accesory nerve lesion

Answer 15

Weakness in turning the head to the opposite side against resistance

Ipsilateral weakness when shoulders are shrugged against resistance

Question 16

Test for long thoracic nerve lesoin

Answer 16

Observation: winged scapula when arm is raised

Abduction of the arm against resistance

Question 17

Test for axillary nerve lesion

Answer 17

Observation: deltoid atrophy

Abduction of the arm against resistance

Test sensation over the lateral aspect of the proximal arm

Question 18

Rotator cuff muscles and their innervation

Answer 18

Supraspinatus - abducts the arm, innervated by the suprascapular nerve

Infraspinatus - externally rotates the arm, innervated by the suprascapular nerve

Teres minor - externally rotates and weakly adducts the arm, innervated by the axillary nerve

Subscapularis - the only rotator cuff muscle that arises from the anterior aspect of the scapula, innervated by the subscapular nerves

Question 19

Location and function of subacromial bursa

Answer 19

Between the supraspinatus tendon and the coracoacromial ligament

Functions to allow the deltoid muscle to move smoothly over the fibrous capsule of the shoulder joint

Question 20

Symptoms and likely cause of rotator cuff injury

Answer 20

Rupture or tear of the supraspinatus tendon is the most common injury

Symptoms:

• Dull ache deep in shoulder
• Disturbed sleep if lying on affected shoulder
• Arm weakness

Question 21

“Frozen Shoulder”

Answer 21

Adhesive fibrosis and scarring of the joint capsule, rotator cuff muscles, subacromial bursa, and deltoid muscle

Question 22

“Shoulder separation”

Answer 22

Dislocation of the acromioclavicular joint (two joint surfaces lose all contact)

In severe dislocation, there is tearing of the acromioclavicular (AC) ligament and coracoclavicular ligament

Question 23

Clavicular fracture (site, presentation, at-risk structures)

Answer 23

The most common clavicular fracture is a midclavicular fracture

Clavicle fractures are fairly common (5% of all adult fractures) and fairly “easy” to do (only 8 lbs of pressure required to break)

Clavicle fractures most often occur following a direct blow to the shoulder.

Symptoms:

• Sagging of the shoulder downward and forward
• Inability to lift the arm because of pain
• A grinding sensation when you try to raise the arm
• A deformity or “bump” over the break
• Bruising, swelling, and/or tenderness over the collarbone

At-risk areas

• The subclavius muscle protects underlying neurovascular structures
• Major neurovascular structures at risk in clavicular fracture include:
• Lateral cord of brachial plexus
• Lateral pectoral nerve
• Axillary artery
• Axillary vein

Question 24

C3 dermatome

Answer 24

Question 25

C4 dermatome

Answer 25

Question 26

C5 dermatome

Answer 26

Test upper lateral arm

Question 27

C6 dermatome

Answer 27

Test pad of thumb

Question 28

C7 dermatome

Answer 28

Test pad of index or middle finger

Question 29

C8 dermatome

Answer 29

Test pad of little finger

Question 30

T1 dermatome

Answer 30

Test medial aspect of elbow

Question 31

T2 dermatome

Answer 31

Question 32

Cutaneous innervation of axillary nerve

Answer 32

Question 33

Cutaneous innervation of radial nerve

Answer 33

Question 34

Cutaneous innervation of musculo-cutaneous nerve

Answer 34

Question 35

Cutaneous innervation of ulnar nerve

Answer 35

Question 36

Cutanious innervation of median nerve

Answer 36