Forelimb Imaging Quiz
Developed by: Sorcha McCaughley & Mark Brims
Approved by: Alison King & Maureen Bain
Supported by: The Chancellor’s Fund
Forelimb Imaging Quiz
START!
Developed by: Sorcha McCaughley & Mark Brims
Supported by: The Chancellor’s Fund
Set the scene…
• Radiography is an essential part of the
veterinary diagnostic process.
• Let’s walk through the basics of the normal
Dog Forelimb.
• Don’t forget the other animals – at the end
you should look at the comparative
species x-rays!
Dog Forelimb
• Choose a question:
–
–
–
–
–
–
Shoulder (Q1)
Shoulder (Q2)
Elbow (Q3)
Elbow (Q4)
Carpus (Q5)
Foot (Q6)
Comparative Forelimb
• Choose a species:
– Cat
– Horse
– Ruminant
– Pig
Dog Shoulder Q1
• (i) What is A?
– Cranial Border
– Scapular spine
– Infraspinous fossa
A
• (ii) What is B?
– Scapular spine
– Acromion process
– Ventral angle
C
B
• (iii) What is C?
– Acromion process
– Glenoid cavity
– Supraglenoid tubercle
 Correct 
• Yes! (A) is the Spine of
the scapula!
Spine
What can you
say about the
age of this dog?
Answer.
• Here are some more
examples.
• Try (ii)!
• Choose a new question.
Spine
A
Answer
• This is a young dog.
• This is indicated by
the presence of
growth plates in the
animal’s bones.
Growth
Plate
Go Back!
• The growth plates
mark the boundaries
between Centres of
Ossification.
 Incorrect 
• No, (A) is not the Cranial
Border.
• The cranial border is
labelled here.
• Try again!
• Choose a new question.
Cranial
border
 Incorrect 
• No, (A) is not the
Infraspinous Fossa.
• The Infraspinous Fossa
is labelled here.
• Try again!
• Choose a new question.
Infraspinous
Fossa
 Correct 
• Yes! (B) is the Acromion
process!
Acromion
Can you tell
which dog is
older?
Answer.
• Here are some more
examples.
• Try (iii)!
• Choose a new question.
Acromion
Answer
• The first dog is
slightly younger.
• Notice how the
growth plate on the
second dog has fused
/ closed. It is still open
in the first dog.
• Go Back!
Growth
Plate
 Incorrect 
• No, (B) is not the
Ventral Angle.
• This x-ray shows the
Ventral Angle.
• Try again!
• Choose a new question.
Ventral Angle
 Incorrect 
• No, (B) is not the
Scapular spine.
• This x-ray shows the
Scapular spine.
• Try again!
• Choose a new question.
Spine
 Correct 
Supraglenoid
Tubercle
• Yes! (C) is the
Supraglenoid Tubercle!
• Here are some more
examples.
• Try Dog Shoulder Q2.
• Choose a new question.
Supraglenoid
Tubercle
Growth
Plate
 Incorrect 
• No, (C) is not the
Acromion process.
• The Acromion process is
labelled in this x-ray.
• Try again!
• Choose a new question.
Acromion
process
 Incorrect 
• No, (C) is not the
Glenoid cavity.
• The Glenoid cavity is
labelled in this x-ray.
• Try again!
• Choose a new
question.
Glenoid
cavity
Dog Shoulder Q2
• (i) What is 6?
– Caudal angle
– Shoulder joint space
– Intertubercular groove
B
• (ii) What is 7?
– Head of Humerus
– Neck of Humerus
– Greater Tubercle
• (iii) What is 8?
– Head of Humerus
– Greater Tubercle
– Intertubercular Groove
• (iv) Do you know what
B is? Answer.
 Correct 
• Yes! (6) is the Shoulder
joint space!
– This is where the Head of
the Humerus articulates
with the Glenoid Cavity of
the Scapula to form the
shoulder joint.
• Here are more
examples.
• Try (ii)!
• Choose a new question.
Shoulder
joint space
Shoulder joint
space
 Incorrect 
• No, (6) is not the Caudal
Angle.
Caudal
Angle
• These x-rays show the
Caudal Angle.
• Try again!
• Choose a new question.
Caudal
Angle
 Incorrect 
• No, (6) is not the
Intertubercular Groove
• The Intertubercular
Groove is labelled in
these x-rays.
• Try again!
• Choose a new question.
Intertubercular
Groove
 Correct 
• Yes! (7) is the Head of
the Humerus!
– Remember: the Head of
the Humerus articulates
with the Glenoid Cavity of
the Scapula to form the
shoulder joint.
Head of
Humerus
• Here are more examples.
• Try (iii)!
• Choose a new question.
Head of
Humerus
 Incorrect 
• No, (7) is not the Neck of
the Humerus.
– Remember: the Neck
extends from the Head to
become the Body of the
Humerus.
Neck of
Humerus
• The Neck of the Humerus
is labelled here.
• Try again!
• Choose a new question.
Neck of
Humerus
 Incorrect 
Greater
Tubercle
• No, (7) is not the Greater
Tubercle.
• The Greater Tubercle is
shown here.
• Try again!
• Choose a new question.
Greater
Tubercle
 Correct 
• Yes! (8) is the Greater
Tubercle!
Greater
Tubercle
• Here are some more
examples.
• Try (iv)!
• Choose a new question.
Greater
Tubercle
 Incorrect 
• No, (8) is not the Head of
the Humerus.
• The Head of the
Humerus is shown here.
• Try again!
• Choose a new question.
Head of
Humerus
Head of
Humerus
 Incorrect 
• No, (8) is not the
Intertubercular Groove.
• The Intertubercular
Groove is shown here.
• Try again!
• Choose a new question.
Intertubercular
Groove
Answer
• B is an Endo-Tracheal
Tube.
• This is placed in the
Trachea to provide
anaesthetic and oxygen
during procedures such
as x-rays and surgery.
• Here is another one.
• Try Dog Elbow Q3
• Choose a new question!
ET tube
Dog Elbow Q3
• (i) What is 1?
– Anconeal Process
– Olecranon Process
– Medial Coronoid Process
• (ii) What is 2?
– Olecranon Process
– Medial Coronoid Process
– Anconeal Process
• (iii) Structure 2 articulates with which
part of 7?
6
5
7
– Olecranon Fossa
– Supracondyloid Foramen
• (iv) What is 5?
– Radius
– Ulna
• (v) What is 6?
– Radius
– Ulna
 Correct 
• Well done! (1) is the
Olecranon process!
– Remember: the
Olecranon Process is the
point of insertion for the
Triceps muscle, the main
extensor muscle of the
elbow.
• Here are more examples
• Try (ii)!
• Choose a new question.
Olecranon
Olecranon
 Incorrect 
• No, (1) is not the
Anconeal Process.
• Here are x-rays showing
the Anconeal Process .
• Try again!
• Choose a new question.
Anconeal
Process
Anconeal
Process
 Incorrect 
• No, (1) is not the Medial
Coronoid Process.
• These x-rays show the
Medial Coronoid
Process.
Coronoid
Process
• Try again!
• Choose a new question.
Coronoid
Process
 Correct 
• Well done! (2) is the
Anconeal Process!
– Remember: the Anconeal
Process articulates with the
Olecranon Fossa of the
Humerus
• Here are some more
examples.
• Try (iii)!
• Choose a new question.
Anconeal
Process
Anconeal
Process
 Incorrect 
• No, (2) is not the
Olecranon process.
• Here are some x-rays
showing the Olecranon
process.
Olecranon
• Try again!
• Choose a new question.
Olecranon
 Incorrect 
• No, (2) is not the Medial
Coronoid Process.
– Remember: the Medial and
Lateral Coronoid Processes of
the radius are the points of
attachment for the annular
ligament that holds the ulna in
place.
Coronoid
Process
• The Coronoid Process is
labelled in these x-rays.
• Try again!
• Choose a new question.
Coronoid
Process
 Correct 
• Well done!
• The Anconeal Process
of the Ulna articulates
with the Olecranon
Fossa of the Humerus!
• Try (iv)!
• Choose a new question.
Anconeal
Process
Olecranon
Fossa
 Incorrect 
• No, the Anconeal Process
does not articulate with
the Supracondyloid
Foramen.
• This x-ray shows the
Supracondyloid foramen
– Remember: this is present
in the cat but not the dog
and blood vessels pass
through it.
• Try again!
• Choose a new question.
Supracondyloid
Foramen
 Correct 
• Yes! (5) is the Ulna!
– Remember: the Ulna has
the large Olecranon
Process proximally and
tapers distally in the dog.
Ulna
• Here are more x-rays of
the Ulna.
• Try (v)!
• Choose a new question.
Ulna
 Incorrect 
• No, (5) is not the
Radius.
Radius
• Here are some x-rays of
the Radius.
• Try again!
• Choose a new question.
Radius
 Correct 
• Yes! (6) is the Radius!
Radius
– Remember: the Radius is
the main weight bearing
bone in the antebrachium
• Here are more x-rays of
the radius.
• Try Dog Elbow Q2!
• Choose a new question.
Radius
 Incorrect 
• No, (6) is not the Ulna.
• Here are some x-rays of
the Ulna.
Ulna
• Try again!
• Choose a new question.
Ulna
Dog Elbow Q4
• (i) What is 7?
– Medial Coronoid Process
– Medial Epicondyle
– Lateral Epicondyle
• (ii) What is 8?
– Anconeal process
– Olecranon process
– Head of Radius
• (iii) What is 12?
– Distal humeral growth plate
– Supracondyloid Foramen
– Olecranon Fossa
 Correct 
• Yes! (7) is the Medial
Coronoid Process!
– Remember: the Medial and
Lateral Coronoid Processes of
the radius are the points of
attachment for the annular
ligament that holds the ulna in
place.
Coronoid
Process
• Here are other x-rays showing the
Medial Coronoid Process.
What can you
say about the
age of this
animal?
Answer.
• Try (ii)!
• Choose a new question.
Coronoid
Process
Answer
• This is a young dog!
• Notice the growth
plates – they are
particularly obvious at
the proximal end of
the radius.
• Go Back!
 Incorrect 
• No, (7) is not the Medial
Epicondyle.
• This x-ray shows the
Medial Epicondyle.
Medial
Epicondyle
• Try again!
• Choose a new question.
 Incorrect 
• No, (7) is not the Lateral
Epicondyle.
• This x-ray shows the
Lateral Epicondyle.
• Try again!
• Choose a new question.
Lateral
Epicondyle
 Correct 
• Yes! (8) is the Olecranon
process!
• Here are more examples.
Olecranon
• Try (iii)!
• Choose a new question.
Olecranon
 Incorrect 
• No, (8) is not the
Anconeal process.
Anconeal
process
• These x-rays show the
Anconeal process.
• Try again!
• Choose a new question.
Anconeal
process
 Incorrect 
Head of
Radius
• No, (8) is not the Head of
the Radius.
• These x-rays show the
Head of the Radius.
• Try again!
• Choose a new question.
Head of
Radius
 Correct 
• Yes! (12) is the
Olecranon Fossa!
• Here is another
example.
• Try Dog Carpus Q1.
• Choose a new question.
Olecranon
Fossa
 Incorrect 
• No, (12) is not the
Distal Humeral growth
plate / physis.
Distal humeral
growth plate
• This x-ray shows the
Distal Humeral growth
plate / physis.
• Try again!
• Choose a new question.
 Incorrect 
• No, (12) is not the
Supracondyloid Foramen.
Supracondyloid
foramen
• Remember: this is only
found in the cat!
• Try again!
• Choose a new question.
This is a kitten foetus. The
supracondyloid foramen
can be seen forming.
Dog Carpus Q5
• (i) What is 2?
Hint: Is this a
young or old
dog?
– Radial Carpal Bone
– Distal Radial Epiphysis
• (ii) What is 4?
– Styloid Process of Ulna
– Ulnar Carpal Bone
• (iii) What is 7?
– Ulnar Carpal Bone
– Accessory Carpal Bone
• (iv) What is 10?
– Second Carpal Bone
– Fourth Carpal Bone
• (v) Do you know the
others now?
– Answers.
 Correct 
• Yes! (2) is the Distal
Radial Epiphysis!
• Here is another
example.
• Try (ii)!
• Choose a new question.
Distal Radial
Epiphysis
 Incorrect 
• No, (2) is not the
Radial Carpal Bone.
Radial
Carpal
Bone
• These x-rays show
the Radial Carpal
Bone.
• Try again!
• Choose a new
question.
Radial
Carpal
Bone
 Correct 
• Yes! (4) is the Styloid
Process of the Ulna!
Styloid
Process
• Here are more
examples.
• Try (iii)!
• Choose a new
question.
Styloid Process
 Incorrect 
• No, (4) is not the Ulnar
Carpal Bone.
• These x-rays show the
Ulnar Carpal Bone.
• Try again!
• Choose a new
question.
Ulnar Carpal
Bone
Ulnar Carpal
Bone
 Correct 
• Yes! (7) is the
Accessory Carpal
Bone!
• Here are more
examples.
• Try (iv)!
• Choose a new
question.
Accessory
Carpal Bone
Accessory
Carpal Bone
 Incorrect 
• No, (7) is not the
Ulnar Carpal Bone.
• These x-rays show
the Ulnar Carpal
Bone.
• Try again!
• Choose a new
question.
Ulnar Carpal
Bone
Ulnar Carpal
Bone
 Correct 
• Yes! (10) is the 4th
Carpal Bone!
• Here are more
examples.
• Try (v)!
• Choose a new
question.
4th
Carpal
Bone
4th
Carpal
Bone
 Incorrect 
• No, (10) is not the 2nd
Carpal Bone.
2nd Carpal
Bone
• The 2nd Carpal Bone
is labelled in these xrays.
2
nd
• Try again!
• Choose a new
question.
Carpal
Bone
Answers
• Try Dog Foot Q1!
• Choose a new question.
• 2 = Distal Radial
Epiphysis
• 4 = Styloid Process of
Ulna
• 5 = Radial Carpal Bone
• 6 = Ulnar Carpal Bone
• 7 = Accessory Carpal
Bone
• 8 = Second Carpal
Bone
• 9 = Third Carpal Bone
• 10 = Fourth Carpal
Bone
Dog Foot Q6
• (i) What is A?
– Fifth Metacarpal Bone
– Proximal Phalanx -1st digit
– Proximal Phalanx - 5th digit
• (ii) What are B?
B
A
– Ungual Process
– Proximal Palmar Sesamoids
– Metacarpal pad
• (iii) What is C?
C
– Metacarpo-phalangeal Joint
– Distal Inter-phalangeal Joint
– Proximal Inter-phalangeal
Joint
 Correct 
• Yes! (A) is the 5th Metacarpal Bone!
• Here is another example.
– Remember: you can use the
location of the 1st digit / dew claw
(if present) to determine which
side of the limb is medial.
– Note though that this image has
been presented with medial to the
left while in the previous example
it was to the right!
• Try (ii)!
• Choose a new question.
1st digit
5th Metacarpal
Bone
 Incorrect 
• No, (A) is not the Proximal
Phalanx – 1st Digit.
• These x-rays show the
1st Digit / dew claw
– Remember: there only 3
bones present in this digit
and there is debate as to
which these are (3
phalanges or metacarpal
+ 2 phalanges)
• Try again!
• Choose a new question.
1st Digit
1st Digit
 Incorrect 
• No, (A) does not show the
Proximal Phalanx – 5th Digit.
Proximal Phalanx
– 5th Digit
• These x-rays show the
Proximal Phalanx – 5th Digit.
– Remember that you can use
the location of the styloid
process of the ulna (*) to
determine which side of the
limb is lateral
• Try again!
• Choose a new question.
*
Proximal
Phalanx
– 5th Digit
 Correct 
• Yes! (B) are the Proximal
Palmar Sesamoids.
• Here is another example.
– Note that the proximal, middle and
distal phalanges have been
amputated from the 5th digit
• Try (iii)!
• Choose a new question.
Proximal Palmar
Sesamoids
 Incorrect 
• No, (B) is not the Ungual
Process.
• This x-ray shows Ungual
Processes.
– Remember that they are
located on the distal
phalanx and support the
nail
• Try again!
• Choose a new question.
Ungual
Processes
 Incorrect 
• No, (B) is not the Metacarpal pad
• These x-rays show the Metacarpal
pad.
– Remember that it is
superimposed over the
metacarpal joints in the DP view
(1st image) but can be seen more
clearly in the lateral view (2nd
image).
• Try again!
• Choose a new question.
Metacarpal
pad
Metacarpal
pad
 Correct 
• Yes! (C) is the Proximal
Inter-phalangeal Joint.
• Here are more
examples, this time of
the 5th digit.
• Look at the comparative
section.
• Choose a new question.
Proximal Interphalangeal Joint
Proximal Interphalangeal Joint
 Incorrect 
• No, (C) is not the Middle
Inter-phalangeal Joint.
• These x-rays show
Metacarpo-phalangeal
Joints.
• Try again!
• Choose a new question.
Metacarpophalangeal
Joint
Metacarpophalangeal
Joint
 Incorrect 
• No, (C) is not the Distal
Inter-phalangeal Joint.
• These x-rays show the
Distal Inter-phalangeal
Joints.
Distal Interphalangeal
Joint
• Try again!
• Choose a new question.
Distal Interphalangeal
Joint
Cat Forelimb – Differences
• Clavicle may be visible
• Scapula
– Suprahamate Process
of Acromion
• Humerus
– Supracondyloid
Foramen
• Ulna & Radius
– Square Olecranon
• Horse Comparative.
Clavicle
Supracondyloid
foramen
Horse Forelimb – Differences
Foal – ulna
fusing to
radius.
Navicular
Bone
3rd Digit bears weight.
2nd & 4th Metacarpals = splint bones
Bones of carpus:
Radial, Intermediate,
Ulnar and Accessory
2nd, 3rd & 4th
• Ruminant Comparative.
Ruminant Forelimb - Differences
Cartilage
plate not
visible in
x-rays
Supratrochlear
Foramen
present in
sheep but not
cattle.
Metacarpals
3 & 4 fused
Radius & Ulna
complete
Bones of Carpus:
Radial, Intermediate,
Ulnar & Accessory
2/3 fused (+)& 4
• Pig Comparative.
+
Digits 3&4
bear weight
Pig Forelimb - Differences
*
Large tuber on
scapular spine (*)
Back to the start.
Radius & Ulna present
and similar diameter.
All carpal bones present:
R/I/U/A
1/2/3/4
4 digits present:
3 & 4 bear weight.