1. Shoulder clinical conditions

Question 1

What is the most common point of fracture of the clavicle?

Answer 1

junction of medial 2/3 and lateral 1/3

Question 2

How are the bone fragments displaced in a clavicle fracture. Why?

Answer 2

• medial fragment displaced SUPERIORLY - by pull of sternocleidomastoid
• lateral fragment displaced INFERIORLY - by weight of upper limb (trapezius unable to hold it up) and MEDIALLY - by pectoralis major adducting the upper limb

Question 3

Which important neurovasculure structures are found posterior to the clavicle?

Answer 3

anterior to posterior: clavicle… subclavian vein… subclavian artery… trunks (and divisions) of brachial plexus

Question 4

Name 3 possible complications of clavicular fractures.

Answer 4

1- damage to underlying vascular structures: subclavian vein and artery

2- damage to trunks and divisions of brachial plexus, or suprascapular nerves

3- pneumothorax due to proximity of lung apex to middle 1/3 of clavicle (chest auscultation must be performed and chest X-ray may be needed)

Question 5

Which structures could be damaged by fracture of surgical neck of humerus?

Answer 5

1- posterior circumflex humeral artery

2- axillary n.

Question 6

Which mov. and sensation would be affected by fracture of surgical neck of humerus?

Answer 6

1. arm abduction - paralysis of deltoid and teres minor

2. sensation at regimental badge area

Question 7

Which structures could be damaged by mid-shaft fracture of humerus?

Answer 7

1- profunda brachii artery
2- radial n.

as are tightly bound in radial groove

Question 8

Which movements/muscles would be affected by radial n. damage at the radial groove?

Answer 8

paralysis of brachioradialis and all extensor muscles of wrist and fingers = WRIST DROP

(little effect on elbow mov. as nerve supply to 3 heads of triceps given off prior to radial n. entering radial groove)

Question 9

Name 2 types of distal humeral fractures that might occur from falling on flexed elbow.

Answer 9

supracondylar and medial epicondyle fractures

Question 10

Which structure might be damaged by a supracondylar humeral fracture?

Answer 10

median n.

Question 11

Which structure might be damaged by a medial epicondyle humeral fracture? How would this affect muscles and sensation?

Answer 11

ulnar n. damage - results in:
1- ulnar claw
2- loss of sensation over medial 1 1/2 fingers (both dorsal and palmar surfaces)

Question 12

Why is the humeral head relatively prone to dislocation?

Answer 12

glenoid fossa is relatively shallow - accepts only about 1/3 of humeral head

Question 13

Why does the humeral head usually dislocate inferiorly?

Answer 13

• CORACOACROMIAL LIGAMENT extends between coracoid process and acromion - prevents superior mov. of humeral head
• GH joint weaker inferiorly

Question 14

In which direction does the humeral head usually displace? Why?

Answer 14

anterior direction due to muscle pull

Question 15

What usually causes anterior shoulder dislocation?

Answer 15

excessive extension and lateral rotation of humerus

Question 16

What usually causes posterior shoulder dislocation?

Answer 16

electric shocks, seizures and lightening strikes

Question 17

How would patients with anterior and posterior shoulder dislocations present differently?

Answer 17

Anterior dislocation:

• external rotation of arm
• slight abduction of arm

Posterior dislocation:

• internal rotation of arm
• adduction of arm
• flattening/squaring of shoulder with prominent coracoid process

Question 18

Which neurovascular structures are at risk of damage in an anterior shoulder dislocation?

Answer 18

1- axillary artery damage
2- axillary n. damage (test for sensation in regimental badge area)
3- brachial plexus damage

Question 19

Which signs would suggest axillary artery damage?

Answer 19

axillary haematoma, cool limb and absent or reduced pulses

Question 20

Name 4 other complications of anterior shoulder dislocations.

Answer 20

1- associated fracture (30% cases), e.g. humeral head, greater tuberosity, clavicle, acromion
2- recurrent shoulder dislocations
3- rotator cuff injuries
4- anatomical lesions: Bankart (avulsion of antero-inferior glneoid labrum) and Hill-Sachs (posterolateral humeral head indentation fracture as soft base of humeral head impacts against relatively hard anterior glenoid) lesions

Question 21

What might cause tears of rotator cuff?

Answer 21

Repetitive use of upper limb above horizontal (e.g. racquet sports)… recurrent inflammation of rotator cuff (esp. relatively avascular area of supraspinatus tendon)… tears of rotator cuff.

Question 22

How might impingement occur at the shoulder joint and what is the result?

Answer 22

Repetitive use of rotator cuff muscles… humeral head and rotator cuff impinge on coracoacromial arch… irritation of arch, degenerative tendinitis of rotator cuff and attrition of supraspinatus tendon.

Question 23

Describe the signs of a torn supraspinatus tendon.

Answer 23

1. failure of initiation of shoulder abduction (0-15 deg.) - but if arm is passively abducted 15 deg., abduction can be maintained/continued (using deltoid)
2. when patient is asked to lower limb slowly and smoothly, limb suddenly drops to side in uncontrolled manner from approx. 90 deg.

Question 24

What is calcific supraspinatus tendinitis?

Answer 24

deposition of calcium (hydroxyapatite) in supraspinatus tendon causing pain and inflammation

Question 25

What might be the result of inflammation in calcific supraspinatus tendinitis?

Answer 25

subacromial bursitis due to irritation of overlying subacromial bursa

Question 26

What is painful arc syndrome?

Answer 26

• pain of abduction of arm from 60-120 deg. and passive mov. resistance in this direction
• pain referred to region of insertion of deltoid
• may result from any disorder of subacromial region

Question 27

What is the sign of calcific supraspinatus tendinitis?

Answer 27

Painful arc syndrome:

• pain in abduction from 50-130 deg. as supraspinatus tendon is in intimate contact with inferior surface of acromion
• no pain in adduction

Question 28

What is adhesive capulitis of GH joint (“frozen shoulder”)?

Answer 28

• adhesive fibrosis and scarring between inflamed capsule of GH joint, rotator cuff, subacromial bursa and deltoid
• causes impaired abduction of arm, but can obtain apparent abduction of up to 45 deg. by elevating and rotating scapula

Question 29

What might cause frozen shoulder?

Answer 29

• shoulder dislocation
• calcific supraspinatus tendonitis
• partial tearing of rotator cuff
• bicipital tendinitis