The Shoulder Joint & The Rotator Cuff Muscles Flashcards Preview

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Flashcards in The Shoulder Joint & The Rotator Cuff Muscles Deck (34):
1

What is the action of the infraspinatus?
How is it innervated?
Where does it attach?

How can this muscle be tested clinically?

Laterally rotates the arm
Suprascapular nerve (C5/6)
Infraspinatus fossa and greater tuberosity

Lateral rotation against resistance
'Lag Test' - elbow flexed, and tucked in to side. Active lateral rotation. Positive when unopposed medial rotation when you let go

2

What is the action of the subscapularis?
How is it innervated?

How can this muscle be tested clinically?

Medially rotates the arm and helps hold the head of the humerus in the glenoid cavity
Subscapular nerve (C5/6)
Subscapular fossa to lesser tuberosity of the humerus

Lift off test/Belly press test

3

What is the action of the teres minor?
How is it innervated?
Where is it attached?

How can we test this muscle clinically?

Laterally rotates the arm
Axillary nerve (nerve roots: C5,C6)
Lateral border of the scapula to greater tuberosity of the humerus

Lateral rotation against resistance
'Lag Test' - elbow flexed, and tucked in to side. Active lateral rotation. Positive when unopposed medial rotation when you let go

4

In the glenohumeral joint, which surfaces articulate?

What covers the articulating surfaces?

Humeral head and the glenoid cavity (the glenoid labrum is a fibrocartilage rim which deepens and stabilises the joint)

Hyaline cartilage

5

What are the three intracapsular ligaments of the glenohumeral joint?

What is their location?

What do they do?

The superior middle and inferior glenohumeral ligaments

They are part of the capsule, they extend between the glenoid labrum and the humerus

They reinforce the capsule anteriorly

6

What are the three extracapsular ligaments of the glenohumeral joint?
Where

Coracohumeral ligament (Coracoid process to the greater tubercle of the humerus)
Coracoacromial ligament (Between the acromion and the coracoid process)
Transverse humeral ligament (It holds the tendon of the long head of the biceps in place during shoulder movement )

7

What does the coraco-acromial arch contain?

What does it do?

Coracoacromial ligament, the acromion, coracoid process of the scapula.
The coraco-acromial ligament is respected in sub-acromial decompression)

Prevents the upper displacement of humerus because it covers the humeral head

8

There is a small space between the acromion of the scapula and the head of the humerus. What does this space contain?

Subacromial bursa
Rotator cuff tendons
Capsule
Tendon of the long head of the biceps

9

What are the two bursa of the glenohumeral joint?

What are their functions?

Subscapular bursa - Facilitates the movement of the tendon of the subscapularis muscle over the scapula

Subacromial bursa - Facilities the movements of the supraspinatus tendon under the caa and the movement of the deltoid muscle over the sj capsule and the greater tubercle of the humerus

10

Which muscles allow flexion at the glenohumeral joint?

Pectoralis major
Anterior fibres of the deltoid
Coracobrachialis
Biceps brachii

11

Which muscles allow extension at the glenohumeral joint?

Posterior fibres of the deltoid
Latissimus dorsi
Teres major

12

Which muscles allow abduction at the glenohumeral joint?

0-15 degrees - supraspinatus
15-90 degrees - deltoid (middle fibres)
Above 90 - trapezius

13

Which muscles allow adduction at the glenohumeral joint?

Pectoralis major
Latissimus dorsi
Teres major

14

Which muscles allow medial rotation at the glenohumeral joint?

Subscapularis
Teres major
Pectoralis major
Latissimus dorsi

15

Which muscles allow lateral rotation at the glenohumeral joint?

Infraspinatus
Teres minor

16

What is the blood supply of the glenohumeral joint?

Anterior and posterior circumflex humeral arteries and suprascapular artery

17

What is the action of the supraspinatus?
How is it innervated?
Where is it attached?

How can this muscle be tested clinically?

Initiation and first 15 degrees of abduction of humerus
Suprascapular nerve (C5/6)
Supraspinous fossa to the greater tuberosity of the humerus

Resistance to 15 degrees of abduction
Empty can test

17

What happens in subacromial bursitis?

Inflammation of the subacromial bursa
Painful arc of movement felt between 60-90 degree of humeral abduction

18

What is meant by frozen shoulder?

What are the key clinical features?

Aka adhesive capsulitis
A syndrome with a spontaneous onset that combines deep aching shoulder pain and restricted movements (both active and passive)
Rotation is significantly affected
Difficulty with ADLs
Sleep disturbance is common
More common with increasing age, diabetes, hypothyroidism

19

What are the management options in frozen shoulder?

Analgesia
Supervised physiotherapy
Intra-articulate joint corticosteroid injection
Secondary care referral
Surgical options include: manipulation under anaesthesia (MUA), arthroscopic surgical release

20

What are the red flags in shoulder pathology?

Infection, unreduced dislocation, suspected tumour, acute rotator cuff tear, neurological pathology

21

What are the signs and symptoms of acromioclavicular arthritis?

Pain on direct palpation, worse with crossing arms over chest to touch shoulders/reach for seat belt, pain in high arch, pain is worse with overhead activities

Scarf test: pain felt when pt asked to bring their arm straight across their body to the other side

X-ray: degenerative LOSS

22

What are the management options in AC arthritis?

Conservative - NSAIDs and modifications to physical activity
Intra-articulate corticosteroid injection
Surgical resection of the distal clavicle 0.5-1.0cm - Mumford procedure

23

What are the phases of frozen shoulder?

What are the possible investigations?

Freezing - painful - gradual onset of diffuse pain (6weeks - 9months)
Frozen - stiffness - decreased ROM affecting ADLs (4-9months)
Thawing - gradual return of motion (5-24 months)

X-ray to distinguish from degenerative changes
MR arthrogram - decreased intra-capsular volume

23

What is a Bankart lesion?

Can be soft or bony
Damage caused by anterior humeral dislocation
Tear of the anterior-inferior glenoid labrum

24

What is a Hill-Sachs lesion?

Damage to the humerus due to anterior dislocation
Cortical impaction injury of the superior-posterior humeral head

Best seen on a Stryker X-ray view

25

What is the mechanism of action of an anterior shoulder dislocation?

What is the management?

Force applied when abducted and externally rotated

Acute reduction and immobilisation
Op: arthroscopic Bankart repair, open repair with capsular shift, remplissage procedure for Hill Sachs

26

What is the mechanism of action of a posterior humeral dislocation?

What is the management?

Trauma with arm flexed, adducted and internally rotated
Common in epilepsy

Acute reduction and immobilisation in external rotation
Op: open/arthroscopic repair

27

What happens in a fracture of the clavicle?

75-80% occur in the middle third segment
FOOSH or direct trauma to the lateral aspect of the shoulder
Medial fragment pulled superiorly by SCM
Lateral fragment pulled inferomedially by the pec major and the weight of the arm

28

What is the management of a fracture of the clavicle?

Assess NV status
Non-op if undisplaced: sling immobilisation with gentle ROM 2-4 weeks and strengthening 6-10 weeks
Op: if displaced with skin tenting, open # - ORIF

29

How can rotator cuff tears be classified?

Acute vs chronic, complete vs partial also
SIT tears (posterior muscles) - common in older patients with degenerative tendinopathy associated with impingement
Subscapularis tear - usually acute in younger patients associated with injury whilst hyperabducted or externally rotated

30

What are the presenting symptoms in rotator cuff tear?

How can tears be investigated and managed?

Usually insidious pain, worse with overhead activities
Night pain
Trauma and acute pain in acute tear
Loss of active but normal passive movement
X-ray, USS, MRI
Mx: NSAIDs, physio, IACS, decompression
Acute repair, tendon transfer, graft jacket, reverse total shoulder arthroplasty

31

What are the complications of anterior shoulder dislocation?

Recurrence
Secondary arthritis
Muscle wasting
Rotator cuff tears
Fractures

32

What clinical test can be used to assess for subacromial impingement?

Hawkins test
Flex both the shoulder and elbow to 90 degrees
Abduct, so the patient's arm is straight out from their side
Whilst maintaining 90' abduction, allow the hand to lower with medial rotation
Then repeat slowly bringing the patient's arm from their side to in front of them