Common shoulder Conditions

Question 1

In which direction do the majority of shoulder dislocations occur?

Answer 1

Anteriorly (90-95%)

Question 2

Why do most shoulder dislocations occur anteriorally?

Answer 2

• shallow glenoid fossa
• joint strengthened superioraly, anterioraly and posterioraly but it is weak inferiorally

Question 3

In what position will the arm be held if a patient presents with an anterior shoulder dislocation?

Answer 3

The arm will be externally rotated and slightly abducted

Question 4

How do anterior dislocations usually occur?

Answer 4

Hand held behind head

-Trauma causes arm to be pushed more posteriorly and the humeral head dislocates forward

Or direct blow to posterior shoulder

Question 5

What 2 injuries occur as a result of a anterior shoulder dislocation? Explain what happens in each

Answer 5

Bankart lesions (labral tear)- part of the glenoid labrum is torn off , sometimes pulling a small piece of bone too

Hill-Sachs lesion- tone of teres minor and infraspinatous muscles causes posterior aspect of humeral head to jam against anterior lip of glenoid fossa causing a dent

Question 6

How likely is it to get the each of the 2 lesions caused by anterior dislocation of the shoulder?

Answer 6

50% bankart

80% Hill-Sachs (more frequent in recurrent dislocation)

Question 7

In what circumstances would you get posterior dislocation of the shoulder?

Answer 7

• electrocution / lightening strike
• violent muscle contractions e.g. epileptic fit
• blow to anterior shoulder
• if arm is flexed across body and pushed posteriorly

Question 8

How do patients with posterior shoulder dislocation usually present at A&E?

Answer 8

Arm internally rotated and adducted

Question 9

What is the rarest form of shoulder dislocation?

Answer 9

Inferior dislocation

Question 10

What is the most common complication of shoulder dislocation? Why does this occur?

Answer 10

Recurrent dislocation

The stabilising tissue surrounding the shoulder is damaged (glenoid labrum, capsule, ligaments)

Question 11

Which nerve is most commonly injured in shoulder dislocation? Explained why this nerve is damaged

Answer 11

The axillary nerve

Nerve wraps around the neck of the humerous and supplies deltoid muscle

Question 12

What injury is always associated with inferior shoulder dislocation?

Answer 12

Rotator cuff muscle tears

Question 13

Where do the majority of clavicle fractures occur?

Answer 13

80% occur in the middle third (mid-clavicular fracture)

Question 14

Most clavicle fractures are treated conservatively, name some circumstances where surgery may be required?

Answer 14

• complete displacement so bone ends cannot unite
• severe displacement causing tenting of the skin (at risk of puncture)
• open fracture
• when there is neurovascular compromise
• floating shoulder
• when the clavicle and glenoid fossa are fractured

Question 15

What happens to the position of the arm in a displaced mid-clavicular fracture?

Answer 15

• arm pulled medially by pec major
• sternocleoidomastoid muscle elevates the medial segment
• the lateral segment drops as trapezium cannot hold it up

Question 16

In a rotator cuff tear, what part of the rotator cuff is most frequently affected?

Answer 16

The tendons more than the muscle, supraspinatus tendon most frequently affected

Question 17

Are most rotator cuff tears acute or chronic? Explain why

Answer 17

Mainly chronic

Most commonly because of age-related degeneration as the blood supply to the rotator cuff reduces with age

Question 18

What is the degenerative micotrauma model in relation to rotator cuff muscle tears?

Answer 18

• age related tendon degeneration
• chronic micro trauma
  
  • inflammatory cells and oxidative stress lead to tendon cell apoptosis
  • Causes partial tears to develop into full rotator cuff tears

Question 19

What are some of the risk factors for rotator cuff tears?

Answer 19

Recurrent lifting and repetitive overhead activity -painter, sports, weightlifting, volleyball

Question 20

Most rotator cuff tears and asymptomatic, but describe the most common clinical presentation

Answer 20

Anterolateral shoulder pain radiating down the arm May occur with activity or leaning on their shoulder

Question 21

What is impingement syndrome?

Answer 21

When the supraspinatus tendon catches on the coraco-acromial arch causing irritation and inflammation

Question 22

What are some of the underlying causes of impingment syndrome?

Answer 22

• thickening of the coracoacromial ligament
• inflammation of supraspinatus tendon
• subacromial osteophytes

Question 23

How does impingement present clinically?

Answer 23

Pain, weakness and reduced range of motion when the shoulder is abducted or flexed

Mainly causes pain at 60-120 degree shoulder abduction

Question 24

What is calcific supraspinatus tendinopathy?

Answer 24

Deposits of hydroxyapitate in the tendon of supraspinatus

Question 25

How does calcific supraspinatus tendinopathy present?

Answer 25

Chronic pain aggravated by abducting or flexing the arm above shoulder level

Mechanical symptoms cause stiffness, snapping sensation, catching and reduced range of shoulder movement

Question 26

What is one of the main theories behind calcific tendinopathy?

Answer 26

Hypoxia → leads to tendocytes being transformed to chondrocytes → which lays down cartilage in tendon → Cartilage is later calcified by endochondrial ossification

Question 27

What happens in adhesive capsulitis (frozen shoulder)?

Answer 27

Inflammation of the glenohumeral joint causing stiffness and pain

Question 28

What aggregates pain in adhesive capsulitis?

Answer 28

• worse and night
• exacerbated by movement
• cold weather
• Pain usually always present

Question 29

What are some of the risk factors for adhesive capsulitis?

Answer 29

• Autoimmune
• shoulder trauma
• female - gender
• epilepsy
• diabetes mellitus
• connective tissue disease
• thyroid disease
• CVD
• breast cancer
• Parkinson’s

Question 30

What is the typical treatment for adhesive capsulitis?

Answer 30

• Physiotherapy
• Analgesia
• Anti-inflammatory medication

Question 31

Which joint is more commonly affected by OA of the shoulder?

Answer 31

Acromioclavicular > glenohumeral