[41] Rotator Cuff Tear

Question 1

What is the rotator cuff?

Answer 1

A group of 4 muscles that support and rotate the glenohumeral joint

Question 2

Are rotator cuff tears common?

Answer 2

Yes - prevalence in gen pop is around 20%

Question 3

What muscles is the rotator cuff composed of?

Answer 3

• Supraspinatus
• Infraspinatus
• Teres minor
• Subscapularis

Question 4

What movement does the supraspinatus do?

Answer 4

Abduction

Question 5

What movement does the infraspinatus do?

Answer 5

External rotation

Question 6

What movement does teres minor do?

Answer 6

External rotation

Question 7

What movement does subscapularis do?

Answer 7

Internal rotation

Question 8

What can rotator cuff tears be classified as

Answer 8

• Acute or chronic

- Partial or full thickness

Question 9

What is considered to be an acute rotator cuff tear?

Answer 9

Lasting <3 months

Question 10

What can full thickness rotator cuff tears be further classified into?

Answer 10

• Small (<1cm)
• Medium (1-3cm)
• Large (3-5cm)
• Massive (>5cm or involves multiple tendons)

Question 11

How much force is required for an acute rotator cuff tear?

Answer 11

Depends - often occur in tendons with pre-existing degeneration, which requires minimal force, however can occur in young individuals when force required to cause tear can be large

Question 12

Who do chronic rotator cuff tears occur in?

Answer 12

Individuals with degenerative microtears to the tendon

Question 13

What causes degenerative microtears to the tendons of the rotator cuff?

Answer 13

• Overuse

- Increasing age

Question 14

What are the main risk factors for rotator cuff tears?

Answer 14

• Age
• Trauma
• Overuse
• Repetitive overhead shoulder motions

Question 15

What are the other risk factors for rotator cuff tears?

Answer 15

• BMI 25
• Smoking
• Diabetes mellitus

Question 16

How will patients with rotator cuff tears present?

Answer 16

Pain over lateral aspect of shoulder and inability to abduct arm above 90 degrees

Question 17

What is found on examination in rotator tuff tears?

Answer 17

• Tenderness over greater tuberosity and subacromial bursa regions
• Supraspinatus and infraspinatus atrophy can be seen in massive years

Question 18

What specific tests can be done to assess for the presence of rotator cuff tears?

Answer 18

• Empty can test
• Gerbers lift off test
• Posterior cuff test

Question 19

What does the ‘empty can test’ test?

Answer 19

Supraspinatus

Question 20

How is the ‘empty can test’ done?

Answer 20

Place the shoulder in 90° abduction and 30° of forward flexion and internally rotate fully (as if you’re ‘emptying a can’). Gently push downwards on the arm.

Question 21

What is a positive empty can test?

Answer 21

Weakness on resistance

Question 22

What does Gerbers lift off test test?

Answer 22

Subscapularis

Question 23

How is Gerbers lift off test done?

Answer 23

Internally rotate the arm so the dorsal surface of hand rests on lower back. Ask the patient to lift hand away from back against examiner resistance.

Question 24

What is a positive Gerbers lift off test?

Answer 24

Weakness in actively lifting the hand away from back (compare to the contralateral side)

Question 25

What does the posterior cuff test test?

Answer 25

Infraspinatus and tees minor

Question 26

How is the posterior cuff test done?

Answer 26

The arm positioned at patient’s side, with the elbow flexed to 90°. The patient is instructed to externally rotate their arm against resistance

Question 27

What is a positive posterior cuff test?

Answer 27

Weakness on resistance

Question 28

What are the main differentials for rotator cuff tears?

Answer 28

- Fracture - Persistent glenohumeral subluxation - Brachial plexus injury - Radiculopathy

Question 29

What investigation should be done urgently in patients presenting with clinical features of a rotator cuff tear?

Answer 29

X-ray (to exclude fractures)

Question 30

What may be found on x-ray in rotator cuff tears?

Answer 30

Most will be unremarkable. In chronic tears, there may be evidence of reduced acromiohumeral distance, or sclerosis and cyst formation the rotator cuff insertion on the greater tuberosity of the humerus.

Question 31

What further imaging can be done in rotator cuff tears once fractures have been excluded?

Answer 31

- Ultrasound | - MRI

Question 32

Why is ultrasound used in rotator cuff tears?

Answer 32

Establish presence and size

Question 33

Why is MRI imaging used in rotator cuff tears?

Answer 33

Detect size, characteristics, and location of eyear

Question 34

What is the management of rotator cuff tears dependant on?

Answer 34

- Type of tear | - Functional status of patient

Question 35

Who is conservative management of rotator cuff tears preferred in?

Answer 35

- Not limited by pain or loss of function | - Significant co-morbidities and unsuitable for surgery

Question 36

How should patients presenting within 2 weeks of the injury be managed?

Answer 36

Should be advised on conservative management approach, but if this fails can be referred for surgical intervention

Question 37

What is involved in the conservative management of rotator cuff tears?

Answer 37

- Analgesia - Physiotherapy - Corticosteroid infections into the subacromial space can be trialled

Question 38

Who should get surgical management for rotator cuff tears?

Answer 38

- Not responding to conservative | - Large or massive tears

Question 39

Who has worse outcomes for surgical repair of rotator cuff tears?

Answer 39

- Large or massive tears - Age >65 - Poor compliance with rehab - Current smokers

Question 40

What is the main complication of rotator cuff tears?

Answer 40

Adhesive capsulitis