Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

MSK > Lecture 14 Clinical Correlates > Flashcards

Lecture 14 Clinical Correlates Flashcards

1
Q

What are some signs of a dislocated shoulder?

A
  • visible deformation
  • swelling
  • bruising around shoulder
  • movement of shoulder will be severely restricted
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the most common form of shoulder dislocation?

A

Anterior (where head of numerous ends up sitting anterior to glenoid fossa)

Glenoid fossa is shallow and the joint is strengthened posteriorly, anteriorly and superiorly, but not inferiorly.
Therefore head of humerus usually dislocated anteroinferiorly, but then displaces in an anterior direction due to pull of muscles and disruption to anterior capsule and ligaments

Alternatively the humeral head may lie anterior-inferior to glenoid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

In anterior dislocation of the shoulder, what position is the arm held in?

A

External rotation, and slight abduction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

When does anterior dislocation usually first occur?

A

Arm positioned in abduction and externally rotated (hand behind head)
-injury forces arm further posteriorly into an extreme position, so humeral head dislocates
OR
Direct blow to posterior shoulder

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is a Bankart lesion?

A

Labral tear
-force of humeral head popping out of its socket causes come of the glenoid labrum to be torn off

Sometimes a small piece of bone can be torn off with the labrum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is a Hill-Sachs lesion?

A

When humeral head is dislocated anteriorly, the tone of the infraspinatus and teres minor means the posterior aspect of the head becomes jammed against the anterior lip of the glenoid fossa causing an indentation fracture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What increases the risk of secondary osteoarthritis in the shoulder joint?

A

Anterior shoulder dislocation

Hill-Sachs lesion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Which type of shoulder dislocation are less common?

A

Posterior
Occur due to violent muscle contraction due to an epileptic seizure/electrocution/lightning strike, when there is a blow to anterior shoulder, when arm is flexed across body and is pushed anteriorly

(You should be thinking about WHY it happened)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How do patients present when they have a posterior shoulder dislocation?

A

Arm internally rotated and adducted

  • squaring of shoulder with prominent coracoid process
  • arm cannot be externally rotated into anatomical position
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Why can a posterior dislocation be missed on an X Ray?

A

It looks like an ‘in-joint’
But because the arm is internally rotated, the humeral head changes to a more rounded shape: LIGHT BULB SIGN
-the glenohumoral distance is also increased

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the clinical relevance of the scapular Y view?

A

The head of the humerus should be directly in line with the glenoid fossa at the bifurcation of the Y.\

Therefore if the humeral head is the the left of right of the Y, it is dislocated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the rarest type of shoulder dislocation?

A

Inferior dislocation

Requires forceful traction on arm when it is fully extended over the head

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What does inferior dislocation cause?

A
  • damage to nerves
  • rotator cuff tears
  • injury to blood vessels
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the most common complication of shoulder dislocation?

A

Recurrent dislocation due to damage to the stabilising tissues surrounding the shoulder
-as we age our tissues loose elasticity so risk of recurrent dislocation decreases as you age

Risk of osteoarthritis also increases with number of dislocations due to damage to humeral head and glenoid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Does the axillary artery occur in shoulder dislocations?

A

Rarely
Commonly in older age group as blood vessels are less elastic

Patient may have haematoma, absent pulses, cool limb

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Do nerve injuries occur in shoulder dislocation?

A

Injuries of the axillary nerve: recover fully as symptoms resolve when shoulder is reduced
As it wraps around the neck of the humerus and supplies the deltoid muscle and skin overlying the insertion of the deltoid = Regimental badge area

Less commonly dislocation of shoulder may damage cords of brachial plexus or the musculocutaneous nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Do fractures occur in shoulder dislocation?

A

Occur in 1/4 of shoulder dislocations, and are more common when the injury is traumatic/first time dislocation/person over 40 yo

Fractures often in head/greater or lesser tubercles of the humerus, clavicle, acromion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

In which age group do rotator cuff muscle tears occur most commonly?

A

Older people but can occur in all age groups

Therefore the integrity of the rotator cuff muscles should be assessed after reduction of the shoulder

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Which age group are clavicle fractures most common?

A

Children and young adults

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the function of the clavicle?

A

Transmits force from upper limb to axial skeleton

Protection to brachial plexus, subclavian vessels and apex of lung

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Where do the majority of fractures occur in the clavicle?

A

Middle 1/3 (midclavicular fracture)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the most common cause of clavicular fracture?

A

Falls onto the affected shoulder

FOOSH

23
Q

How are clavicular fractures treated?

A

Conservatively via a sling

Some are treated surgically

24
Q

What are the indications for surgical fixation of the clavicle?

A
  • complete displacement (bone ends not in appposition so can’t unite)
  • severe displacement causing tenting of the skin with risk of puncture
  • open fractures
  • neurovascular compromise
  • fractures with interposed muscle (muscle in between)
  • floating shoulder (clavicle fracture with ipsilateral fracture of glenoid neck)
25
Q

What will happen to the position of the arm and clavicular fragments in a displaced mid-clavicular fracture?

A
  • sternocleidomastoid muscle elevates the medial segment
  • trapezius muscle is unable to hold the lateral segment up against the weight of the upper limb, the shoulder drops
  • arm pulled medially by pectoralis major
26
Q

What are some local complications with a fractured clavicle?

A

Pneumothorax (lung collapse)
Injury to surrounding neurovascular structures
-suprascapular nerve may be damaged by elevation of medial part of the fracture
-supraclavicular nerve may be damaged causing paraesthesia over upper chest anteriorly

27
Q

Which tendon of the rotator cuff muscles is most commonly affected?

A

Supraspinous tendon. Where is passes beneath the coracoacromial arch, tearing at its site of insertion on the greater tubercle of the humerus

28
Q

Which functions of the rotator cuff are compromised if you get a tear?

A

Abduction
Externally rotating
Internally rotating
Stabilising the glenohumoral joint

29
Q

Are rotator cuff tears chronic or acute?

A

Chronic (acute tears can occur)

  • result from extended use in combination with poor biomechnics/muscular imbalance
  • age-related degeneration (blood supply decreases, impairing body’s ability to repair minor injuries)
  • DEGENERATIVE-MICROTRAUMA MODEL: age-related tendon degeneration, compounded by chronic microtrauma results in partial tendon tears which develop into full rotator cuff tears
30
Q

Why does further degeneration occur after a rotator cuff tear?

A

Inflammatory cells are recruited and oxidative stress leads to tenocyte (tendon cell) apoptosis

31
Q

What are risk factors for rotator cuff tears?

A

-lifting
-repetitive overhead activity
-sports involving overhead motion (swimming, tennis)
More common in shoulder of dominant arm, but a tear in one shoulder increases the risk of a tear in the other shoulder

32
Q

What are the symptoms of a rotator cuff tear?

A

Usually asymptomatic

  • anterolateral shoulder pain radiating down the arm
  • pain in shoulder when leaning on elbow as it pushes the head of the humerus superiorly decreasing the space between the humeral head and the coracoacromial arch
  • pain when flexing the shoulder (reaching forward)
  • weakness in shoulder abduction (often only found on examination)
33
Q

How would you diagnose and treat a rotator cuff tear?

A

MRI and ultrasound, as well as history and examination

Treatment: rest/analgesia, or operative

34
Q

When does impingement syndrome occur?

A

When the supraspinous tendon impinges on coraco-acromial arch leading to irritation and inflammation

35
Q

What is the usual space between the humeral head and coracoacromial arch?

A

1-1.5 cm

36
Q

What is impingment caused by?

A

Narrowing of space between the humeral head and coracoacromial arch

  • thickening of coracoacromial ligament
  • inflammation of supraspinatus tendon
  • subacromial osteophytes (osteoarthritis)
37
Q

What movements cause pain in impingement syndrome?

A

Abduction/flexion, as the space becomes narrowed further

  • overhead movements
  • patient lying on affected shoulder
38
Q

What is the pain described as in impingement syndrome?

A

Acute: if due to an injury
Insidious (gradually increasing): due to gradual process such as osteophyte formation
DULL PAIN, lingers for long time, making it hard to fall asleep at night
-can feel a popping/grinding sensation on movement of the shoulder

39
Q

What is the most common form of impingment syndrome?

A

Impingememt of the supraspinatus tendon during abduction of the shoulder
= painful arc between 60-120 degrees
(brushing their hair/reaching from high cupboard)

40
Q

What is calcific supraspinatus tendinopathy?

A

Macroscopic deposits of hydroxyapatite (crystalline form of calcium) in the tendon of the supraspinatus (can occur in any tendon of rotator cuff, but most commonly here)

41
Q

When do you experience pain in calcific supraspinatus tendinopathy?

A

-Abduction/flexion of the arm above level of shoulder
-lying on shoulder
Mechanical symptoms
-physical appearance of large deposit, leading to stiffness, snapping sensation, catching, reduced range of movement

42
Q

Theories behind calcific supraspinatus tendinopathy?

A
  • regional hypoxia leads to tenocytes being tranformed into chondrocytes and laying down cartilage in tendon, calcium deposits are formed through process resembling endochondral ossification
  • ectopic bone formation via metaplasia of mesenchymal stem cells
43
Q

How do you image calcific deposits?

A

X-Ray

44
Q

When do calcific deposits cause the most pain?

A

Resting phase: crystalline

Eventually reabsorbed by phagocytes: PAIN, during this stage they look like toothpaste and appear cloudy

45
Q

What is the treatment of calcific supraspinatus tendinopathy?

A

Rest and analgesia

Surgical treatment is also required if persistent symtoms

46
Q

What is adhesive capsulitis also known as?

A

Frozen shoulder

  • capsule of the glenohumeral joint becomes inflamed and stiff, restricting movement and chronic pain
  • pain is constant and worse at night, made worse by movement and cold weather
47
Q

Cause of frozen shoulder?

A

Unknown (may be autoimmune response triggered by trauma)
Risk factors
-female
-epilepsy with tonic seizures (sudden muscle contractions)
-trauma to shoulder
-diabetes mellitus (glucose molecules bond to capsular collagen)

48
Q

Why do some people with frozen shoulder develop depression?

A

Severe pain and sleep deprivation

-interference with their work and activities

49
Q

What is the treatment for frozen shoulder?

A

Physiotherapy, analgesia, anti-inflammatory medication

-manipulation under anaethesia which breaks up scar tissue and adhesions to restore range of motion

50
Q

Does frozen shoulder resolve?

A

Yes over time. Patients gain 90% of shoulder motion

-opposite shoulder becomes affected in 6-17% of patients within 5 years suggesting autoimmune hypothesis

51
Q

Which joint in the shoulder is most affected by osteoarthritis?

A

Acromioclavicular joint

52
Q

Which age group is most affected by osteoarthritis of the shoulder?

A

> 50 years

53
Q

How do you treat osteoarthritis?

A
  • activity modification
  • analgesia
  • NSAIDS (anti-inflammatories)
  • nutritional supplements
  • steroid injections (reduce swelling and alleviate shoulder stiffness/pain)
  • hyaluronic acid injections into joint may increase lubrication
54
Q

What types of surgery are performed on someone with a osteoarthritic shoulder?

A
  • arthroscopy (key hole) to remove loose pieces of damaged cartilage from glenohumeral joint
  • hemiarthroplasty (replacement of humeral head)
  • total shoulder replacement (of humeral head and gelnoid)

MSK (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions