PCE appendicular skeleton

Question 1

Comment components

Answer 1

Location
Fracture orientation
Open or closed? (only mention if open)
Simple or comminuted? (Only mention if comminuted)
intra-articular?
Displacement and/or angulation

Question 2

How to construct a PCE

Answer 2

A WHAT: There is a …. (name type) fracture/dislocation
OF WHICH AREA: of the… (e.g., proximal, lateral, middle third etc.)
OF WHICH BONE: of the … (e.g., left, right, humerus, phalanx, talus etc.)
WITH WHAT: with … displacement (e.g., no, minimal, marked, anterior etc.)
AND WHAT: and … angulation (e.g., no, radial, ulnar, medial etc.)
WHAT ELSE: There is also… (e.g. artefact, ST swelling, lipohaemarthrosis, air etc.)

Question 3

The clavicle notes
Tend to fracture in the middle third or distal third
Descriptions can be difficult
Does it involve the ACJ?
Common in children

Answer 3

Tend to fracture in the middle third or distal third
Descriptions can be difficult
Does it involve the ACJ?
Common in children

Question 4

Clavicle PCE example (slide 7)

Answer 4

Always describe the distal component
There is a transverse fracture of the midshaft of the left clavicle with marked inferior displacement of two shaft’s width.

Question 5

ACJ Disruption notes
assess ACJ (slide 9)

How to assess disruption?

Answer 5

dont need to describe the types
amount of force determines extent of injury
Disrupted AC ligament and then disrupted coracoclavicular ligaments which allows the clavicle to elevate.

We can assess the joint quite easily by utilising a single Line of assessment
We are only interested in the inferior margin as the superior margin is not a reliable measure.

Question 6

What is a Hill-Sachs Deformity?

Answer 6

a posterolateral humeral head depression fracture, resulting from the impaction with the anterior glenoid rim and indicative of an anterior glenohumeral dislocation

it looks like the clavicle is in the the humeral head/ it happens when there is an anterior dislocation.

Posterior dislocation with a reverse Hill-Sachs, it works like part of the scapula in the humeral head

Question 7

What is a Bankart’s Lesion?

Answer 7

injuries specifically at the anteroinferior aspect of the glenoid labral complex and represent a common complication of anterior glenohumeral. They are frequently seen in association with a Hill-Sachs defect).

Bankart lesion on a patient with a history of recurrent dislocation (slide 16)
it looks like a chipped part of the scapula at the gleno

Question 8

Shoulder dislocations appearance

Answer 8

95% are anterior
medial and anterior with head beneath coracoid

Posterior dislocations
the humeral head rotates so it has the appearance of a lightbulb but it may still appear like its in #place”

Question 9

If there is a dislocation, ask three questions
is it anterior or posterior ?
is there a glenoid rim fracture?
is there a compression # of humeral head ?

Answer 9

If there is a dislocation, ask three questions
is it anterior or posterior ?
is there a glenoid rim fracture? Bankart’s Lesion
is there a compression # of humeral head ? Hill-Sachs Deformity

Question 10

Humeral Fractures (note)
Most are as part of a comminuted #
Commonly affects the surgical neck and greater tuberosity
Distal humeral component often displaced medially due to pulling of the pectoralis
Shaft fractures are often spiral with a butterfly fragment
Common place for metastatic deposits

Answer 10

Humeral Fractures (note)
Most are as part of a comminuted #
Commonly affects the surgical neck and greater tuberosity
Distal humeral component often displaced medially due to pulling of the pectoralis
Shaft fractures are often spiral with a butterfly fragment
Common place for metastatic deposits

Question 11

There is a severely medially displaced and laterally angulated transverse fracture through the surgical neck of the humerus with an associated, comminuted fracture of the greater tuberosity. The GH joint appears preserved. (slide 22)

Example PCE

Answer 11

severely medially displaced (displacement)
laterally angulated transverse fracture (angulation)
surgical neck of the humerus (location)
an associated, comminuted fracture of the greater tuberosity (type and location)
The GH joint appears preserved.

Question 12

The radiocapitellar line tells us what?

Answer 12

The Radiocapitellar Line – what does it tell us….it helps us identify a radial head dislocation Might seem obvious but a dislocated radial head on a bad elbow projection is easily missed.

Question 13

Where should the humeral line bisect?

Answer 13

The anterior humeral line should bisect approximately the middle third of the capitulum.

Question 14

what should the fat pads on the elbow appear like?

Answer 14

You will always see an anterior fat pad…but it should not be elevated. The posterior fat pad will only be visible with a significant joint effusion….usually indicating a fracture.
if there is an injury it gives a sail sign

Question 15

CRITOL meaning

Answer 15

Capitellum
Radial head
Internal epicondyle
Trochlea
Olecranon
Lateral epicondyle

Question 16

If you have a Trochlea, Olecranon and Lateral Epicondyle then you should already have a medial (internal) epicondyle; if this is missing, it is significant, why?

Answer 16

We have a trochlea and lateral epicondyle so we must have a medial/internal epicondyle….but it isn’t there….it has been pulled away and is tucked inside the joint

Question 17

Radial head fractures are (note flashcard)
Most common adult elbow fracture (Just over 50%)
Always Intra-articular
Usually seen affecting the anterolateral aspect
Can be occult
Caused by a FOOSH mechanism
Check for associated dislocation
Likely will require adapted technique
Consider a radial head view

Answer 17

Always Intra-articular
Usually seen affecting the anterolateral aspect
Can be occult

Question 18

Which way has this dislocated? Remember to talk about the distal component. (note slide)

What has fractured?

Posterior dislocation of the elbow joint with an associated fracture of the coronoid process

Posterior and postero-lateral dislocations of the radius and ulna account for 80-90% of all elbow dislocations…commonly seen with a fracture of the coronoid process which you can see here

Answer 18

Which way has this dislocated? Remember to talk about the distal component.

What has fractured?

Posterior dislocation of the elbow joint with an associated fracture of the coronoid process

Posterior and postero-lateral dislocations of the radius and ulna account for 80-90% of all elbow dislocations…commonly seen with a fracture of the coronoid process which you can see here

Question 19

Fractures of radius/ulna are 10 times more common than carpal injuries (note slide)

Age 4-10 transverse fracture often greenstick

11-16 radial epiphyseal fracture

17-40 scaphoid fracture

40 plus Colle’s

Carpal fractures are rare in children

These age ranges are only approximate and should be employed as a guideline only when looking at your images.

Younger children are more likely to have buckle/torus fracture…usually seen at the posterior aspect of the distal radial metaphysis

Answer 19

Fractures of radius/ulna are 10 times more common than carpal injuries

Age 4-10 transverse fracture often greenstick

11-16 radial epiphyseal fracture

17-40 scaphoid fracture

40 plus Colle’s

Carpal fractures are rare in children

These age ranges are only approximate and should be employed as a guideline only when looking at your images.

Younger children are more likely to have buckle/torus fracture…usually seen at the posterior aspect of the distal radial metaphysis

Question 20

There is a minimally posteriorly displaced and angulated transverse fracture through the distal radius with an associated minimally displace fracture through the ulnar styloid. (slide 41)

Answer 20

displacement (posteriorly/anteriorly, laterally/medially)
angulation
of which bone/s
type of fracture? e.g transverse

Location
Fracture orientation
Open or closed? (only mention if open)
Simple or comminuted? (Only mention if comminuted)
intra-articular?
Displacement and/or angulation

Question 21

Moderately anterolaterally displaced transverse fracture are seen through the distal radius and ulna. (slide 42)

Scaphotrapeziotrapezoidal (STT) and 1st carpo-metacarpal joint (CMCJ) degenerative change noted. (Tri-scaphoid Osteoarthritis – Aberdeen Virtual Hand Clinic)

Answer 21

remember its the distal part of the fracture you speak about

Question 22

Why do we do lots of projections for the scaphoid?

Answer 22

It is because of it’s blood supply. It’s retrograde so we worry about avascular necrosis and non-union. This would drastically affect the functionality of the wrist and we saw earlier that it more commonly affects a younger age group (17-40) so they have longer to live with the difficulties.

The waist can heal well if it is treated quickly and is non-displaced. But To treat it quickly…we must first spot it!

The proximal pole tends not to heal well at all and often results in non-union.

Question 23

What is the carpal fracture called when there is a bit of the bone in the posterior area of the hand? slide 49

Answer 23

The triquetral fracture is the second most common carpal bone to fracture and we often only see it on the lateral.

Its called the pooping duck sign.

Question 24

Types of lunate carpel dislocations?

Answer 24

Lunate dislocation (the lunate dislocates, rest is okay
Peri lunate dislocation (lunate is fine but the rest of the capitate has dislocated)
Midcarpal dislocation (everything has dislocated)

Question 25

What does a lunate dislocation look like on PA wrist/hand x-ray? slide 53

Answer 25

Note the pyramidal shape of the lunate on the right. This can be seen in perilunate dislocations too and is caused by the rotation of the lunate. slide 53

Question 26

peri lunate dislocation (note slide)
See how the lunate has rotated but remains congruent with the distal radius (lunate fossa) and the capitate has moved posteriorly

Answer 26

peri lunate dislocation (note slide)
See how the lunate has rotated but remains congruent with the distal radius (lunate fossa) and the capitate has moved posteriorly

Question 27

Hand/finger
There is a moderately anteriorly displaced and angulated fracture through the neck of the fifth metacarpal. (slide 57) note slide

Answer 27

Hand/finger
There is a moderately anteriorly displaced and angulated fracture through the neck of the fifth metacarpal. (slide 57) note slide

Question 28

Hip fractures (note flashcard)
Fractures occur at characteristic sites
Some can be very subtle or occult
Signs to spot the more difficult fractures: -
Are cortical margins continuous or is there a subtle step?
Is the trabecular pattern continuous or disrupted?
Does a dense white line cross the femoral neck?
Is there a valgus deformity to the femoral head & neck?
Pitfalls

Answer 28

Hip fractures tend to occur at specific sites which is useful to know and aids our interpretation. However, some can be very subtle indeed and even occult on plain film.

Question 29

what are the 2 main types of hip fractures?

Answer 29

There are 2 main types of hip fracture, each containing sub-divisions.

We describe them in relation to the joint capsule. Intracapsular and extracapsular.

Capsule extends to the intertrochanteric region

Question 30

4 types of intra capsular fractures and 3 types of extra capsular fractures.

Capital fractures (Not shown here) are very rare.

subcapital fractures occur where the head meets the neck and sometimes have an oblique component that makes them look transcervical but the HBL will show you that it is a true subcapital #.

Subcapital fractures are so common that they have their own classification system.

Subcapital and intertrochanteric tend to be the most common with subcapital accounting for 63% (approximately) of presentations. Transcervical and basicervical fractures are rarer.

A subtrochanteric fracture should raise the suspicion of underlying pathology as this is a common place for metastatic deposits….but these can occur without underlying pathology with high energy force vectors.
(note flashcard)

Answer 30

4 types of intra capsular fractures and 3 types of extra capsular fractures.

Capital fractures (Not shown here) are very rare.

subcapital fractures occur where the head meets the neck and sometimes have an oblique component that makes them look transcervical but the HBL will show you that it is a true subcapital #.

Subcapital fractures are so common that they have their own classification system.

Subcapital and intertrochanteric tend to be the most common with subcapital accounting for 63% (approximately) of presentations. Transcervical and basicervical fractures are rarer.

A subtrochanteric fracture should raise the suspicion of underlying pathology as this is a common place for metastatic deposits….but these can occur without underlying pathology with high energy force vectors.

Question 31

Types of intracapsular fractures?

Answer 31

Subcapital
Transcervical
Basicervical

Question 32

Types of extracapsular fractures?

Answer 32

Intertrochanteric
Subtrochanteric
Avulsion

Question 33

Subtle hip fracture note slide 62
these get missed all the time. Look at the external rotation to the leg…and the subtle mushroom like deformity to the head and neck creating a very subtle valgus deformity.
A valgus deforminty is where the angle between the axis of the nof and the axis of the shaft is greater than 135 degrees

Notice the large step at the posterior neck
HBL gets us a much better look at the neck

Answer 33

Subtle hip fracture note slide 62
these get missed all the time. Look at the external rotation to the leg…and the subtle mushroom like deformity to the head and neck creating a very subtle valgus deformity.
A valgus deforminty is where the angle between the axis of the nof and the axis of the shaft is greater than 135 degrees

Notice the large step at the posterior neck
HBL gets us a much better look at the neck

Question 34

Intracapsular Fracture Checklist
Assess the trabeculae for disruption or angulation
Assess both radiographs for a subtle cortical step
Look for impacted sclerotic line
Assess for abnormal angulation of the femoral head/neck (varus/valgus)

Answer 34

Intracapsular Fracture Checklist
Assess the trabeculae for disruption or angulation
Assess both radiographs for a subtle cortical step
Look for impacted sclerotic line
Assess for abnormal angulation of the femoral head/neck (varus/valgus)

Question 35

(note slide 71)
Mostly comminuted - trochanters as separate fragments
More comminution = more unstable
Fractures extending into subtrochanteric area are inherently unstable due to opposite pull of adductors and abductors

Answer 35

Mostly comminuted - trochanters as separate fragments
More comminution = more unstable
Fractures extending into subtrochanteric area are inherently unstable due to opposite pull of adductors and abductors

Question 36

note slide 72
The sub trochanteric region is said to be up to 5cm distal to the lesser trochanter although this varies from textbook to textbook.

There are 3 main population groups: -

Elderly = falls
Young = High velocity trauma
Pathological bone = Mets or Osteoporosis (Bisphosphonate Tx). Common place for metastatic deposits.

An oblique, subtrochanteric fracture is seen through the right femur.

Answer 36

The sub trochanteric region is said to be up to 5cm distal to the lesser trochanter although this varies from textbook to textbook.

There are 3 main population groups: -

Elderly = falls
Young = High velocity trauma
Pathological bone = Mets or Osteoporosis (Bisphosphonate Tx). Common place for metastatic deposits.

An oblique, subtrochanteric fracture is seen through the right femur.

Question 37

(hip dislocations note slide)
Posterior dislocations are most common…so it’s the opposite to the shoulder. Tend to be associated with posterior wall acetabular fractures and less commonly, femoral head fractures

Some posterior dislocations may present with nerve palsy/neurology due to the position of the sciatic nerve

Anterior dislocations are rarer with a lower incidence of associated acetabular fractures but is associated with femoral head fractures

Central ‘dislocations’ are those where the femoral head is forced through the acetabulum and migrates medially….obviously always associated with a fracture(s).

Answer 37

Posterior dislocations are most common…so it’s the opposite to the shoulder. Tend to be associated with posterior wall acetabular fractures and less commonly, femoral head fractures

Some posterior dislocations may present with nerve palsy/neurology due to the position of the sciatic nerve

Anterior dislocations are rarer with a lower incidence of associated acetabular fractures but is associated with femoral head fractures

Central ‘dislocations’ are those where the femoral head is forced through the acetabulum and migrates medially….obviously always associated with a fracture(s).

Question 38

What is the appearance of posterior hip dislocations usually?

Answer 38

Commonly seen in RTAs where the hip is in flexion and the impact on knee pushes femoral head posteriorly

Dislocations tend to have very specific positions and this is most commonly associated with posterior dislocations. We look at the position of the head of the femur as well as the direction and rotation of the femur.

Posterior = limb adducted (the direction of the limb towards the midline) and internally rotated (cannot see the lesser trochanter)

Question 39

What is the appearance of anterior hip dislocations usually?

Answer 39

Classic position of an anterior dislocation. Note the markedly different position of the femoral head and differing rotation of the shaft.

Hip usually dislocates inferiorly to over lie obturator foramen = commonest

Limb = neutral/abducted (away from the midline), external rotation, lateral will confirm (although in most cases shouldn’t be necessary).

Remember to assess particularly carefully for associated femoral head or acetabular fractures

Question 40

What is the appearance of central hip dislocations usually?

Answer 40

Usually more obvious than this.
Some ambiguity has to whether we should call these dislocations. Usually you end up describing the fracture anyway and stating the medial displacement/migration of the femoral head. We will discuss fractures of the acetabulum and how to interpret how many columns are involved in our axial session.

These are more common than you might think.

Question 41

Slipped Upper Femoral Epiphysis
important information for spotting them?

Answer 41

Look for widened growth plate

Line drawn along lateral femoral neck should intersect femoral epiphysis

Use the line of Klein to spot the subtle ones

Question 42

knee (slide 80)

Question 43

(note slide 81)
The soft tissues signs…much like the elbow….are really important for accurate interpretation of knee trauma.
Intra articular # - lipohaemarthrosis
Fat (lucent) on top of denser blood like oil on water
Indicates # even if not seen
Must be HBL

Answer 43

Intra articular # - lipohaemarthrosis
Fat (lucent) on top of denser blood like oil on water
Indicates # even if not seen
Must be HBL

Question 44

Patella fractures

Only account for 1% of fractures in the body.

Tend to be caused by a direct blow.

Patella fractures will not always produce a lipohaemarthrosis, although one is visible here.

Can be comminuted (sometimes referred to as stellate), vertical or transverse.

Avoid skylines in the presence of a patella fracture….

Transverse fractures can readily displace due to the opposing pull of the patella tendon.

Answer 44

Only account for 1% of fractures in the body.

Tend to be caused by a direct blow.

Patella fractures will not always produce a lipohaemarthrosis, although one is visible here.

Can be comminuted (sometimes referred to as stellate), vertical or transverse.

Avoid skylines in the presence of a patella fracture….

Transverse fractures can readily displace due to the opposing pull of the patella tendon.

Question 45

slide 84 (note slide)
tibial plateau fractures
The knee is a very complex joint….tibial plateau fractures can be associated with rupture of med collateral ligament and the cruciate ligaments if extending into the intercondylar eminence

Lateral plateau most common

They are usually caused by a twisting force and an axial load

They can be incredibly subtle (like the one on the left) and really easily missed - look for lucency, sclerosis, depression

The picture on the left demonstrates a subtle depression fracture made more obvious by the oblique projection. A good radiographer may go ahead and produce two oblique views to aid interpretation if they or the clinician suspect a tibial plateau fracture.

Answer 45

The knee is a very complex joint….tibial plateau fractures can be associated with rupture of med collateral ligament and the cruciate ligaments if extending into the intercondylar eminence

Lateral plateau most common

They are usually caused by a twisting force and an axial load

They can be incredibly subtle (like the one on the left) and really easily missed - look for lucency, sclerosis, depression

The picture on the left demonstrates a subtle depression fracture made more obvious by the oblique projection. A good radiographer may go ahead and produce two oblique views to aid interpretation if they or the clinician suspect a tibial plateau fracture.

Question 46

What are Multiple exostoses/ osteochondromas?

Answer 46

Pointy bits of bone (slide 86)

Multiple exostoses/ osteochondromas arising from metaphysis
point away from the joint
Asymptomatic but can become large, and can fracture
Now commonly referred to as multiple hereditary exostoses

Hereditary condition forming multiple osteochondromas throughout the skeleton.

Question 47

Ankle Fractures
Ring structure – seek another injury
Widening of joint indicative of ligament disruption
Medial and lateral collateral ligaments

Where could we see injuries in the ankle?

Answer 47

Ankle injuries are far more complex than you might first think.

The ‘ankle mortice’ (talocrural joint) forms a ring so we follow Neer’s ring analogy (two breaks in a ring is unstable). The ankle is a soft ring though meaning that is made up of ligamentous components…therefore it can be injured in one place.

The second injury however, may be a ligamentous one so we need to look for subtle joint space widening. The most common ligament to rupture first in the anterior tibiofibular ligament and this may only elicit a joint effusion and soft tissue swelling. You may see widening of the syndesmosis.

On the right we can see subtle widening of the medial ankle mortice, with overlying soft tissue swelling indicating rupture of the deltoid ligament complex (medial collateral ligaments). We can also see subtle lateral talar shift. A fracture should be suspected involving the proximal Fibula

Question 48

What is a masionneueve injury?

Answer 48

Fractures of the fibula neck are commonly associated with a more significant ankle injury more distally.

If you see marked widening of the medial ankle mortice with significant lateral talar shift…expect a fracture of the proximal fibula in a pattern called a Maisonneuve injury.

Question 49

Paediatric Ankle Fractures (note slide 91)

Essentially, a Tillaux (left) fracture is a Salter-Harris III fracture caused by a twisting force. Can be as innocuous as a simple inversion injury.

This twisting force would normally rupture the anterior tibiofibular ligament in an adult but in the paediatric skeleton the physis is weaker and so allows a characteristic avulsion injury.

Right- You can see it involves the medial margin and is caused by tension from the deltoid ligament, rather than tension in the anterior tibiofibular ligament.

Answer 49

Paediatric Ankle Fractures (note slide 91)

Essentially, a Tillaux (left) fracture is a Salter-Harris III fracture caused by a twisting force. Can be as innocuous as a simple inversion injury.

This twisting force would normally rupture the anterior tibiofibular ligament in an adult but in the paediatric skeleton the physis is weaker and so allows a characteristic avulsion injury.

Right- You can see it involves the medial margin and is caused by tension from the deltoid ligament, rather than tension in the anterior tibiofibular ligament.

Question 50

Talar Fractures (note slide 92)

Check talar dome for osteochondral #

Osteochondritis Dissecans

Avulsion # dorsal surface head of talus

Can involve the head, neck body or posterior process. It is also susceptible to avulsion fractures and osteochondral fractures (pictured here at the bottom)

Answer 50

(note slide 92)

Check talar dome for osteochondral #

Osteochondritis Dissecans

Avulsion # dorsal surface head of talus

Can involve the head, neck body or posterior process. It is also susceptible to avulsion fractures and osteochondral fractures (pictured here at the bottom)

Question 51

Sub-Talar Dislocation (note slide 94)
There are different types of talar dislocation depending on which joints are involved but this is the most common.

Most commonly we see sub-talar dislocations - Dislocation of the talocalcaneal joint and often including dislocation of the talonavicular joint as well.…usually has an element of angulation/rotation.

Answer 51

Sub-Talar Dislocation (note slide 94)
There are different types of talar dislocation depending on which joints are involved but this is the most common.

Most commonly we see sub-talar dislocations - Dislocation of the talocalcaneal joint and often including dislocation of the talonavicular joint as well.…usually has an element of angulation/rotation.

Question 52

Calcaneal Fractures (note slide 95)
We use something called Bohler’s angle to assess the calcaneum for fractures. (the angle on a lateral ankle/calcaneum projection between a line joining the highest point of the anterior process of the calcaneus and the highest point of the posterior articular facet, and a line joining the highest point of the posterior articular facet with the highest point of the calcaneal tuberosity)

Bohler’s angle should be 20-40 degress (Normal on the right) Abnormal left….it’s quite subtle.

Answer 52

Calcaneal Fractures (note slide 95)
We use something called Bohler’s angle to assess the calcaneum for fractures. (the angle on a lateral ankle/calcaneum projection between a line joining the highest point of the anterior process of the calcaneus and the highest point of the posterior articular facet, and a line joining the highest point of the posterior articular facet with the highest point of the calcaneal tuberosity)

Bohler’s angle should be 20-40 degress (Normal on the right) Abnormal left….it’s quite subtle.

Question 53

What is a Lisfranc Fracture-Dislocation?

Answer 53

Widening of the metatarsals away from the tarsus bone in the foot

Injury mechanisms are varied and include:
direct crush injury or an indirect load onto a plantarflexed foot 3

forefoot abduction-type injuries where the hindfoot is fixed and there is rotation around the joint such as changing direction with a foot planted firmly i.e. with cleats or football boots (this is the classic ‘horse stuck in stirrup mechanism)

forced plantar-flexion where the plantarflexed foot undergoes significant axial loading

They can shift laterally

Question 54

How to spot a Lisfranc Fracture-Dislocation?

Answer 54

Assess for co-linearity of the medial base of the second MT with the medial border of the middle cuneiform.

Assess for widening of the base of 1st and 2nd MT.

Look for a small bony fleck in the space.

Any ideas of a projection you can do that really helps stopping these getting missed?
A weight-bearing DP…..a lateral can also be performed.

Question 55

Fifth metatarsal (note slide 103)
Very common
Usually at the base
Often intra-articular
Associated with lateral malleolus injuries

Very common avulsion fracture caused by tension at the insertion of ?? the peroneus brevis (mostly) and plantar fascia insertion

Commonly missed on the lateral ankle

Answer 55

Fifth metatarsal (note slide 103)
Very common
Usually at the base
Often intra-articular
Associated with lateral malleolus injuries

Very common avulsion fracture caused by tension at the insertion of ?? the peroneus brevis (mostly) and plantar fascia insertion

Commonly missed on the lateral ankle

“Minimally displaced transverse (or avulsion, either or) fracture through the base of the fifth metatarsal (PCE for 104 slide)