Radiology Review

Question 1

What are the labels?

Answer 1

1a - sternal end

1b - mid-shaft

1c - acromial end

2a - acromion

2b - spine

2c - coracoid process

2d - glenoid fossa

2e - medial border

3a - lesser tubercle

3b - greater tubercle

3c - head of humerus

Question 2

What are the labels?

Answer 2

1a - distal shaft

1b - lateral epicondyle

1c - olecranon fossa

1d - medial epicondyle

1e - capitulum

1f - trochlea

2a - radial head

2b - radial tuberosity

3a - olecranon

3b - coronoid process

Question 3

What are the labels?

Answer 3

1 - humerus

2a - radial head

2b - radial tuberosity

3a - olecranon

3b - coronoid process

Question 4

What are the labels?

Answer 4

1a - distal shaft of radius

1b - styloid process of radius

2a - ulna distal shaft

2b - styloid process of ulna

3 - scaphoid

4 - lunate

5 - triquetrium

6 - pisiform

7 - trapezium

8 - trapezoid

9 - capitate

10 - hamate

Question 5

Clinical case: A 46 year old man was thrown from his bike. He had pain and deformity of his right shoulder.

What can you see? What is your diagnosis based on the patient’s presentation? Would you request an X-ray?

Answer 5

• Protrusion of right clavicle
  
  • Dislocation of acromion from clavicle (AC joint)
• Need to do X-ray
  
  • To see extent of dislocation and confirm diagnosis

Question 6

Does this x-ray confirm diagnosis of AC dislocation?

Answer 6

Yes - separation of acromion and clavicle

Question 7

Clinical case: A 20 year old man fell whilst playing football. He had pain and deformity of his right shoulder. He cannot move it.

What can you see? What is your diagnosis? Do you need to request an X-ray?

Answer 7

• Angular appearance of right shoulder
• Shoulder dislocation (probably anterior dislocation of humeral head)
  
  • Acromion forming angle due to humeral head not being where it’s supposed to
• Need an x-ray:
  
  • To confirm anterior dislocation
  • To confirm extend of injury (can get fractures associated with dislocations)
  • Need to do x-ray before and after putting shoulder back into place (in case you have made it worse)

Question 8

In what dislocations would you need to do a bilateral x-ray (i.e. of the other side)?

Answer 8

Posterior shoulder dislocation - can occur on both sides

Question 9

X-ray for: A 20 year old man fell whilst playing football. He had pain and deformity of his right shoulder. He cannot move it.

Does the X-ray confirm your diagnosis? What can you see in the X-rays?

Answer 9

AP view:

• Yes - can see humeral head has been anteriorly dislocated and is not articulating with the glenoid fossa

Need a 2nd view to confirm: Y-view

• Head of humerus isnt sat in middle of Y but instead is sat immediately beneath the coracoid process

Question 10

What are the 2 blue labels?

Answer 10

Coracoid process and head of humerus (seen here in anterior shoulder dislocation)

Question 11

What is an AP view?

Answer 11

Anteroposterior view - the x-ray beam enters through the anterior aspect and exits through the posterior aspect of the chest.

Question 12

What is a Y-view?

Answer 12

The Y-view is taken by aligning the x-ray beams parallel to the plane of the scapula so that it can be seen “floating” over the thoracic wall. In a healthy patient, the humeral head should be in alignment with the glenoid cavity of the scapula.

Question 13

What is the radial styloid? What is the ulna styloid?

Answer 13

Styloid process is found at the distal end of both the ulna and the radius - is a projection of bone

Radial - projection on the lateral surface of the distal radius

Ulna - projection on the medial surface of distal ulna

Question 14

What nerve is most at risk during an anterior shoulder dislocation?

Answer 14

Axillary nerve

Question 15

Clinical case: A 68 year old man fell whilst out walking his dog. His X-ray is shown.

Which part of the humerus is fractured?

Which nerve is vulnerable to injury and how may this present clinically?

What do you need to examine?

Answer 15

• Surgical neck fracture
• Axillary nerve at risk
• Need to examine motor and sensory function of nerve:
  
  • Motor: deltoid and teres minor
  • Sensory: sensation over upper lateral arm

Question 16

Clinical case: You are asked to review the X-rays of a 30 year old man on the Acute Medicine ward. He was admitted yesterday via A&E with generalised tonic-clonic seizure. Overnight he complained of pain in his right shoulder and the on-call doctor requested X-rays.

What do you make of the patient’s X-rays? What has happened?

Answer 16

• Posterior dislocation
• Humeral head has rotated
  
  • Be careful as can look like humeral head is sat in glenoid fossa
• In y-view: confirms posterior dislocation
  
  • Humeral head sat under acromion

Question 17

What are the classic causes of posterior shoulder dislocation?

Answer 17

• Can be caused by trauma
• Mainly caused by seizures; severe muscle contraction which can be enough to posteriorly dislocate the shoulder
  
  • Can cause bilateral shoulder dislocation
• Electrocution can also cause (bilateral) shoulder dislocation

Question 18

Clinical case: An 87 year old man fell at home. He had pain, deformity and bruising of his left arm. His X-ray is shown.

Which part of the humerus has been fractured?

What do you need to do in your examination of this patient?

Answer 18

• Oblique fracture of the humerus
• Radial nerve at risk
  
  • To examine motor: extend wrist
  • Sensory: sensation over dorsal lateral aspect of hand and over ASB

Question 19

During humeral shaft fractures that may affect the radial nerve, why is it better to test the motor function of the wrist than elbow?

Answer 19

As radial nerve comes down arm, the radial nerve has already given off some branches to triceps so will still get some extension at the elbow

Question 20

Clinical case: A 13 year old boy fell whilst playing with friends. His left arm was very painful and swollen.

What injury has been sustained?

What structures are vulnerable to injury?

How would you examine this patient?

Answer 20

• Supracondylar fracture - this injur is more common in children than adults; typical mechanism is a fall onto the outstretched hand (FOOSH)
• Median nerve and brachial artery at risk
• Examine median nerve:
  
  • Flexion of fingers (make a fist)
• Examine brachial artery:
  
  • Colour, temperature of hand

Question 21

More subtle supracondylar fracture x-rays.

Answer 21

Question 22

What are elbow fat pads?

Answer 22

A potential finding on elbow radiography which suggests a fracture of one or more bones at the elbow:

• The elbow joint has 2 regions of fat around it: anterior and posterior fat pads

Question 23

Which elbow fat pads are visible on an x-ray?

Answer 23

Often the small anterior fat pad can be seen on a normal lateral elbow x-ray

The posterior fat pad is never visible on a normal xray

Question 24

What is an intraarticular fracture? How can it present on an x-ray?

Answer 24

A fracture inside the joint capsule - can cause bleeding and swelling inside the capsule

This pushes up against the fat pads and pushes them away from the humerus - become more visible on x-rays as dark grey areas anterior and posterior to the joint

Question 25

Normal vs visible fat pads

Answer 25

Left: small anterior fat pad and no posterior fat pad Right: large anterior fat pad, visible posterior fat pad

Question 26

When might you look for fat pads?

Answer 26

When fractures are subtle and can easily be missed

Question 27

Why are elbow x-rays in children different?

Answer 27

* Parts of the bones of the radius and ulna and distal humerus develop, form and ossify during childhood (between 1-11 years). * While they're developing, it can be difficult to interpret their x-rays

Question 28

In what order do the bony landmarks in the elbow ossify in childhood?

Answer 28

CRITOE: capitulum **first**, radial head, internal (medial) epicondyle, trochlea, olecranon, external (lateral) epicondyle **last**

Question 29

Clinical case: A 38 year old woman fell whilst out running. Her right elbow was deformed and very painful. She could not move it. Her X-ray is shown below. What has happened here? Are there any structures at risk? What must you do as part of your examination?

Answer 29

* Posterior ulna/elbow dislocation * Ulnar nerve at risk (as runs behind the medial epicondyle)

Question 30

What do you think about this X-ray? Where are the fractures and what is unusual about both of them? What are these types of fractures called?

Answer 30

* X-ray of a child; tiny carpal bones, distal ends of radius and humerus haven't properly formed * Greenstick, radius and ulna fractures

Question 31

What is a greenstick fracture?

Answer 31

* When a bone bends and cracks instead of breaking * Most occur in children younger than 10

Question 32

Clinical case: A 21 year old man tripped and fell whilst out running. He put out his right arm to break his fall. Can you make the diagnosis based on the appearance of the wrist? Do you need an X-ray?

Answer 32

* **Colles' fracture:** fracture of the distal radius, where the distal portion becomes dorsally displaced * Need an xray: extent of injury, gives more info to help you put back into place

Question 33

What is a Colles' fracture?

Answer 33

A type of fracture of the distal forearm in which the broken end of the radius is bent backwards.

Question 34

The lateral view in a Colles' fracture is very important. Why?

Answer 34

Can tell you extend of radius displacement

Question 35

This person has a distal radius fracture. What is the doctor doing?

Answer 35

* Haematoma block - local anaesthetic is injected into the haematoma that will have formed between the broken ends of the 2 bones * This numbs the area so you can then do the reduction

Question 36

Clinical case: A 43 year old man tripped and fell 24 hours ago. He has discomfort at the bottom of his right thumb. There is no bruising or deformity, but there is some tenderness in the ASB. Do you need an X-ray?

Answer 36

Yes. There might be a scaphoid fracture. X-ray seen here. Xray: * Scaphoid seems fine * Need another angle * BUT need to still treat patient as if there is a scaphoid fracture: can't always see them on initial xrays as can develop and appear later (a few days)

Question 37

What is a 'scaphoid series'?

Answer 37

4 views taken of the scaphiod: posteroanterior, oblique, lateral and angled posteroanterior projection