Shoulder Joint

Question 1

What are both the articulating surfaces of the glenohumeral joint covered in?

Answer 1

Hyaline cartilage

Question 2

Where does the joint capsule of the shoulder extend to?

Answer 2

From the border of the glenoid fossa to the anatomical neck of the humerus

Question 3

What kind of membrane lines the fibrous sheath of the joint capsule? What is the benefit of this?

Answer 3

Synovial membrane

Produces synovial fluid which reduced friction between articulating surfaces

Question 4

How is friction reduced in the shoulder joint?

Answer 4

There are several synovial bursae

Question 5

What is a synovial bursae?

Answer 5

Synovial fluid filled sac which acts as a cushion between tendons and other joint structures

Question 6

Name the two clinically important bursae

Answer 6

Subacromial and subscapular

Question 7

What does the subacromial bursae do?

Answer 7

Supports the deltoid and supraspinatus muscles

Question 8

What does the subscapular bursae do?

Answer 8

Reduced wear and tear on subscapularis tendon during movement at the shoulder joint

Question 9

Name the 3 ligaments of the shoulder joint

Answer 9

Glenohumeral ligaments (superior,middle, inferior)
Coracohumeral ligament
Transverse humeral ligament
Coracoacromial ligament

Question 10

What are the attachments of the glenohumeral ligaments?

Answer 10

Run with the joint capsule from the joint capsule to the anatomical neck of the humerus

Question 11

What is the action of the glenohumeral ligaments?

Answer 11

To stabilise the anterior aspect of the shoulder joint

Question 12

What is the attachment of the coracohumeral ligament?

Answer 12

Attaches to the base of the coracoid process to the greater tubercle of the humerus

Question 13

What is the action of the coracohumeral ligament?

Answer 13

Supports the superior part of the joint capsule

Question 14

What are the attachments of the transverse humeral ligament?

Answer 14

Spans distance between the two tubercles of the humerus

Question 15

What is the action of the transverse humeral ligament?

Answer 15

Hold the tendon of the long head of the bicep in the bicipital groove

Question 16

What are the attachments of the coracoacromial ligament?

Answer 16

Runs between the acromion and the coracoid process of scapula (forms coraco-acromial arch)

Question 17

What is the action of the coracoacromial ligament?

Answer 17

Prevents superior displacement of the humeral head

Question 18

What is different about the coracoacromial ligament compared to the other 3 ligaments of the shoulder joint?

Answer 18

It is not a thickening of the joint capsule

Question 19

What is the arterial blood supply to the shoulder joint?

Answer 19

Anterior and posterior circumflex humeral arteries

Suprascapular artery

Question 20

What is the innervation of the shoulder joint?

Answer 20

Supplied by the axillary, suprascapular and lateral pectoral nerves (derived from roots C5 and C6)

Question 21

What kind of injury would affect the innervation of the shoulder joint function?

Answer 21

An upper brachial plexus injury (Erb’s palsy)

Question 22

What muscles permit extension at the shoulder?

Answer 22

Posterior deltoid, latissimus dorsi and teres major

Question 23

What muscles permit flexion at the shoulder?

Answer 23

Bicep brachii, pectoralis major, anterior deltoid and coracobrachialis

Question 24

What muscles permit adduction at the shoulder?

Answer 24

Pectoralis major, latissimus dorsi, teres major

Question 25

What muscles permit abduction at the shoulder?

Answer 25

0-15 degrees- supraspinatus 15-90 degrees- middle deltoid fibres 90 + degrees - trapezoid and serratus anterior (rotate scapular)

Question 26

What muscles permit medial rotation at the shoulder?

Answer 26

``` Subscapularis Pectoralis major Latissimus doris Teres major Anterior deltoid ```

Question 27

What muscles permit lateral rotation at the shoulder?

Answer 27

Infraspinatus and teres minor

Question 28

What are the factors contributing to the mobility of the shoulder joint?

Answer 28

- the fact that it is a ball and socket joint - the disproportionate size of articulating surfaces - laxity of joint capsule

Question 29

What are the factors that contribute to the stability of the shoulder joint?

Answer 29

Rotator cuff muscles Glenoid labrum Ligaments

Question 30

How are dislocation of the shoulder joint described?

Answer 30

By where the humeral head lies in relation to the infraglenoid tubercle

Question 31

What is the more common type of shoulder dislocation?

Answer 31

Anterior dislocation

Question 32

What is anterior dislocation usually caused by?

Answer 32

Excessive extension and lateral rotation of the humerus | Humeral head is forced anteriorly and inferiorly- into the weakest part of the joint capsule

Question 33

Which two nerves can be effected by dislocations?

Answer 33

Axillary and radial

Question 34

What does injury to the axillary nerve cause?

Answer 34

Paralysis of deltoid and loss of sensation over regimental badge area

Question 35

What does rotator cuff tendinitis do to the shoulder joint over time?

Answer 35

Causes degenerative changes in the subacromial bursa and subsequently the supraspinatus tendon- increased friction between structures

Question 36

What is a characteristic sign of rotator cuff tendonitis?

Answer 36

Painful arc pain in the middle of abduction (where affected area comes into contact with the acromion)

Question 37

Posterior shoulder dislocations are less common and can easily be missed clinically and on x-ray. But how could these sort of breaks occur?

Answer 37

Electric shock, seizures

Question 38

How would someone present clinically with a posterior shoulder dislocation?

Answer 38

They wouldn't be able to externally rotate at the shoulder because it is fixed in internal rotation

Question 39

How would you fix a clavicle fracture? What are the risks of this?

Answer 39

Wires and surgery Wires may break and cause damage elsewhere

Question 40

Name a common degenerative condition of the shoulder joint

Answer 40

Calcification tendonitis- calcium hydroxyapatite deposit- tendon turns to bone

Question 41

What is popeye muscle? How is it treated

Answer 41

When the long head of the bicep ruptures and causes a bulging in the arm. This is just cosmetic there is no need for surgery

Question 42

How would someone with impingement of the shoulder joint present clinically?

Answer 42

Low painful arc (once arm is past 90 degrees its fine) Tender over tuberosity Hawkins test +ive

Question 43

How would you treat someone with impingement of the shoulder joint?

Answer 43

Steroids and physio Or surgical decompression

Question 44

What complications may occur after anterior dislocation of the shoulder?

Answer 44

Damage to axillary nerve. Axillary nerve runs posteriorly to head of humerus so dislocation anteriorly will pull on the axillary nerve.

Question 45

How would examine a patient who had dislocated their shoulder to determine the integrity of the axillary nerve? What would you not do and why?

Answer 45

Test for sensation at regimental badge area (where injections happen) Test for motor function in acute trauma