Thoracic Body Wall & Vertebral
Column Imaging Quiz
Developed by: Sorcha McCaughley & Mark Brims
Approved by: Alison King & Maureen Bain
Supported by: The Chancellor’s Fund
Thoracic Body Wall & Vertebral Column
Imaging Quiz
START!
Developed by: Sorcha McCaughley & Mark Brims
Supported by: The Chancellor’s Fund
Thoracic Body Wall Vertebral Column
• Thoracic Inlet Q1
• Diaphragm Q2
• Ribcage Q3
• Typical Vertebra Q4
• Cervical Vertebrae Q5
• Clinical Considerations
Q6
Thoracic Inlet Q1
Feline
• (i) Which boundary of the
Thoracic Cavity is formed by the
Thoracic Inlet?
– Cranial
– Lateral
– Caudal
• (ii) Which bone forms the dorsal
boundary of the Thoracic Inlet?
– 2nd thoracic vertebra
– 7th cervical vertebra
– 1st thoracic vertebra
• (iii) What forms the ventral
boundary of the thoracic inlet?
– 2nd sternebra
– Xiphoid
– Manubrium
 Correct 
• Yes! The Thoracic Inlet
is the Cranial border of
the Thorax!
Feline
• It is shown here in
these x-rays.
• Try (ii)!
• Choose a new question.
Canine
 Incorrect 
• No, the Thoracic Inlet is
not the Lateral
boundary of the Thorax.
• The Ribs (arrows) and
Muscles make up the
Lateral boundaries.
• Try again!
• Choose a new question.
Canine
 Incorrect 
• No, the Thoracic Inlet is
not the Caudal
boundary of the Thorax.
• The Caudal boundary is
the Diaphragm.
• Try again!
• Choose a new question.
Canine
 Correct 
• Yes! The dorsal boundary of
the Thoracic Inlet is formed
by the 1st Thoracic
Vertebra!
• It is shown here in these xrays.
• Orange = Cervical vertebrae
• Blue = 1st Thoracic vertebra
• Try (iii)!
• Choose a new question.
Feline
 Incorrect 
• No, the 2nd Thoracic
Vertebra does not form
the dorsal boundary of
the Thoracic Inlet .
• The 2nd Thoracic vertebra
is shown in this x-ray
• Try again!
• Choose a new
question.
 Incorrect 
• No, the 7th Cervical
Vertebra does not form
the dorsal boundary of
the Thoracic Inlet .
• The 7th Cervical
vertebra is shown in
this x-ray
• Try again!
• Choose a new
question.
 Correct 
• Yes! The ventral
boundary of the
Thoracic Inlet is formed
by the Manubrium or
1st Sternebra!
• This is shown in this xray.
• Try (iv)!
• Choose a new question.
Feline
 Incorrect 
• No, the ventral boundary
of the Thoracic Inlet is not
formed the 2nd sternbra.
• The 2nd sternebra is shown
in this x-ray.
• Try again!
• Choose a new
question.
 Incorrect 
• No, ventral boundary of
the Thoracic Inlet is not
formed the Xiphoid.
• The Xiphoid or last
sternebra is shown in this
x-ray.
• Try again!
• Choose a new
question.
Diaphragm Q2
Canine
• (i) What are the attachments of
the Diaphragm?
– Thoracic vertebrae & Sternebrae
– Lumbar vertebrae & Xiphoid
– Abdominal wall
• (ii) During which stage of
respiration does the diaphragm
flatten caudally towards the
abdomen?
– Inspiration
– Expiration
 Correct 
• Yes! The Diaphragm
attaches to the Lumbar
Vertebrae and Last
Sternebra or Xiphoid.
• Try (ii)!
• Choose a new question.
Feline
 Incorrect 
• No, the Diaphragm does not
attach to the Thoracic
Vertebrae and Sternebrae.
– The Diaphragm forms the
caudal boundary of the
thoracic cavity so these
structures are located too far
cranial
• Try again!
• Choose a new question.
 Incorrect 
• No, the Diaphragm does not attach to the
Abdominal Wall.
• Remember: the Diaphragm is the most
important muscle involved in respiration and
needs to be securely attached to bone!
– The abdominal wall is composed of muscle and
soft tissue only.
• Try again!
• Choose a new question.
 Correct 
• Yes! The Diaphragm flattens caudally during
Inspiration.
• When the Diaphragm contracts during
inspiration, it flattens. This increases the
volume of the thoracic cavity which draws air
into the lungs.
• Try Q3 on the Ribcage!
• Choose a new question.
 Incorrect 
• No, the Diaphragm does not flatten caudally
during expiration.
• Remember: during expiration, the volume of
the thoracic cavity reduces and air is moved
out of the lungs. The Diaphragm relaxes and
becomes dome shaped , bulging cranially into
the ribcage.
• Try again!
• Choose a new question.
Ribcage Q3
Canine
• (i) How many pairs of ribs does a dog
have?
– 14
– 13
– 18
• (ii) Which of these is one of the
proximal articulations of Rib 5?
– Head of Rib  Cranial Costal Fovea of
Thoracic Vertebra 5
– Head of Rib  Cranial Costal Fovea of
Thoracic Vertebra 4
– Tuberculum  Transverse Process of
Thoracic Vertebra 6
• (iii) What is the distal articulation of
Rib 5?
– Costal Arch
– No attachment – ‘Floating Rib’
– Inter-sternal Cartilage
 Correct 
• Yes! A dog has 13 pairs
of ribs!
• Here they are labelled
in this x-ray.
• Try (ii)!
• Choose a new question.
 Incorrect 
• No, the dog does not have 14 pairs of ribs.
• Pigs can have 14-16 pairs of ribs!
• Try again!
• Choose a new question.
 Incorrect 
• No, the dog does not have 18 pairs of ribs.
• The horse has 18 pairs of ribs!
• Try again!
• Choose a new question.
 Correct 
• Yes! The Head of Rib 5 articulates with the Cranial
Costal Fovea of Thoracic Vertebra 5!
• The Head of Rib 5 also articulates with
the Caudal Costal Fovea of Rib 4.
• The Heads of Ribs 11-13 only articulate
with the Cranial Costal Fovea of their
corresponding Vertebrae.
• Try (iii)!
• Choose a new question.
T4
T5
Rib 5
 Incorrect 
• No, the Head of Rib 5 does not articulate with
the Cranial Costal Fovea of Thoracic Vertebra
4.
• It is the head of rib 4 that articulates
with the cranial costal fovea of T4
and also the caudal costal fovea of T3.
• Try again!
• Choose a new question.
T3
T4
Rib 4
 Incorrect 
• No, the Tuberculum of Rib 5
does not articulate with the
Transverse Process of Rib 6.
T5
• The Tuberculum of Rib 5 articulates
with the Transverse Process of Rib 5!
• Try again!
• Choose a new question.
Rib 5
 Correct 
• Yes! The distal attachment of Rib 5 is to the InterSternal Cartilage!
• This is true of Ribs 1-9
• The Inter-Sternal Cartilage is not usually visible on xrays as it is not a bony structure.
• Ribs 10-12 attach to the
Costal Arch and Rib 13
is a ‘Floating Rib’.
• Move on to the Vertebral Column!
• Choose a new question.
 Incorrect 
• No, the distal attachment of Rib 5 is not to the
Costal Arch.
• Ribs 10-12 attach to
the Costal Arch!
• Try again!
• Choose a new question.
 Incorrect 
• No, Rib 5 does have a distal attachment.
• It is Rib 13 that is
the ‘Floating Rib’!
• Try again!
• Choose a new question.
Typical Vertebra Q4
• (i) What is A?
– Vertebral Foramen
– Obturator Foramen
– Intervertebral Foramen
• (ii) What is B?
– Dorsal Spinous Process
– Vertebral Arch
– Transverse Process
C
B
A
• (iii) What is C?
– Transverse Process
– Dorsal Spinous Process
– Body of Vertebra
• (iv) Do you know where in the
spine this vertebra is from?
How can you tell?
– Answer.
 Correct 
• Yes! (A) is the Vertebral
Foramen!
• Here are more examples.
– Remember – the spinal cord
runs through here
Vertebral
Foramen
C1 or Atlas
Vertebral
Foramen
• Try (ii)!
• Choose a new question.
 Incorrect 
• No, (A) is not the
Obturator Foramen.
• Remember: the
Obturator Foramen is
found in the Pelvis!
• Try again!
• Choose a new question.
Obturator
Foramen
 Incorrect 
• No, (A) is not the
Intervertebral Foramen.
• The Intervertebral
Foramen is shown in this
x-ray.
– Remember : it is located
between adjacent vertebra
• Try again!
• Choose a new question.
Intervertebral
Foramen
 Correct 
• Yes! (B) is the
Transverse Process!
• Here are more
examples.
Transverse
Process
• Try (iii)!
• Choose a new question.
Transverse
Process
 Incorrect 
• No, (B) is not the Dorsal
Spinous Process.
• The Dorsal Spinous
Process is shown in
these x-rays.
• Try again!
• Choose a new question.
Spinous
Process
Spinous
Process
 Incorrect 
• No, (B) is not the
vertebral Arch.
Vertebral
Arch
• The Vertebral Arch is
shown in these x-rays.
• Try again!
• Choose a new question.
Vertebral
Arch
 Correct 
• Yes! (C) is the Dorsal
Spinous Process!
Spinous
Process
• Here are more
examples.
Spinous
Process
• Try (iv)!
• Choose a new question.
 Incorrect 
• No (C) is not the
Transverse Process.
• The Transverse Process
is shown in these x-rays.
Transverse
Process
• Try again!
• Choose a new question.
Transverse
Process
 Incorrect 
• No, (C) is not the Body
of the Vertebra.
• The Body of the
Vertebra is shown in
these x-rays.
Vertebral
Body
• Try again!
• Choose a new question.
Vertebral
Body
Answer
• This Vertebra is from the Thoracic region of a
cat.
– You can tell because of the
long dorsal spinous process,
the very short transverse processes
and the presence of ribs (arrow)!
• Try Cervical Vertebrae Q5!
• Choose a new question.
Cervical Vertebrae Q5
• (i) What is A?
A
– C2
– C1
• (ii) What is another name for B?
– Axis
– Atlas
• (iii) Which of the following
allows ‘universal ’ movement
between the skull and the
vertebral column?
B
– Atlanto-Occipital Joint
– Atlanto-Axial Joint
– Occipito-Atlanto-Axial Complex
 Correct 
• Yes! A is the first
cervical vertebra or C1!
C1
• Here are x-rays of C1
• Try (ii)!
• Choose a new question.
Transverse
processes or
‘Wings’ of C1
 Incorrect 
• No, A is not C2 which is
the 2nd cervical
vertebra!
C2
• These x-rays show C2.
• Try again!
• Choose a new question.
C2
 Correct 
• Yes! B is the 2nd cervical
vertebra or C2 which is
also known as the Axis!
Axis
• These x-rays show the
Axis.
• Try (iii)!
• Choose a new question.
Axis
 Incorrect 
• No, B is not also known
as the Atlas.
Atlas
• These x-rays show the
Atlas.
– Remember: It is the 1st
cervical vertebra or C1
that is known as the
atlas.
• Try again!
• Choose a new question.
Wings of
Atlas
 Correct 
• Yes! It is the Occipito-Atlanto-Axial
Complex that allows universal
movement.
• The combination of flexion
between the skull & C1 + rotation
between C1 & C2 allows full
movement of the skull relative to
the vertebral column while
protecting the spinal cord from
damage
• Try Clinical Considerations Q6!
• Choose a new question.
AtlantoAtlanto- Axial
Occipital
OccipitoAtlanto-Axial
 Incorrect 
• No, the AtlantoOccipital Joint does not
allow ‘universal’
movement
• Movement at this joint
is restricted to flexion
and extension
– Remember: this is the
‘yes’ joint as it allows
nodding of the head!
• Try again!
• Choose a new question.
Atlanto-Occipital joint
 Incorrect 
• No, the Atlanto-Axial
Joint does not allow
‘universal’ movement
• Movement at this joint
is restricted to lateral
rotation
– Remember: this is the
‘no’ joint as it allows
shaking of the head!
• Try again!
• Choose a new question.
AtlantoAxial
Clinical Considerations Q6
• Do you know what
space the needle is in?
– Answer.
• What structure is
outlined when
radiographic contrast
medium is injected into
the subarachnoid
space?
– Answer.
Answer
• The needle is in the Cisterna Magna.
• A Cerebro-Spinal Fluid sample can be taken from this
area.
• Radiographic contrast medium
can be injected to help visualise
soft tissue structures not
normally seen in x-rays.
• Try (ii)!
• Choose a new question.
Answer
• The Spinal Cord is outlined after radiographic
contrast medium is injected into the Sub-Arachnoid
Space .
• This can be achieved via the cisterna magna or in the
lumbar region, as shown in this x-ray.
• This technique is called myelography and was used to
assess the spinal cord before the advent of advanced
imaging techniques such as MRI and CT.
• Back to the Start!