Thoracic Body Wall & Vertebral Column Imaging QuizDeveloped by: Sorcha McCaughley & Mark BrimsApproved by: Alison King & Maureen BainSupported by: The Chancellor’s Fund

Thoracic Body Wall & Vertebral Column Imaging Quiz

START!

Developed by: Sorcha McCaughley & Mark BrimsSupported by: The Chancellor’s Fund

Thoracic Body Wall

• Thoracic Inlet Q1• Diaphragm Q2• Ribcage Q3

Vertebral Column

• Typical Vertebra Q4 • Cervical Vertebrae Q5• Clinical Considerations

Q6

Thoracic Inlet Q1 • (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

Feline

Correct • Yes! The Thoracic Inlet

is the Cranial border of the Thorax!

• It is shown here in these x-rays.

• Try (ii)!• Choose a new question.

Feline

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 x-rays.

• 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 questio

n.

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 questi

on.

Correct • Yes! The ventral

boundary of the Thoracic Inlet is formed by the Manubrium or 1st Sternebra!

• This is shown in this x-ray.

• 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 questio

n.

Diaphragm Q2• (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

Canine

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• (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

Canine

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.

Rib 5

T4 T5

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.

Rib 4

T3 T4

Incorrect • No, the Tuberculum of Rib 5

does not articulate with the Transverse Process of Rib 6.

• The Tuberculum of Rib 5 articulates with the Transverse Process of Rib 5!

• Try again!• Choose a new question.

T5

Rib 5

Correct • Yes! The distal attachment of Rib 5 is to the Inter-

Sternal Cartilage!• This is true of Ribs 1-9• The Inter-Sternal Cartilage is not usually visible on x-

rays 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

• (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.

AB

C

Correct • Yes! (A) is the Vertebral

Foramen!

• Here are more examples.– Remember – the spinal cord

runs through here

• Try (ii)!• Choose a new question.

Vertebral Foramen

Vertebral Foramen

C1 or Atlas

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.

• Try (iii)!• Choose a new question.

Transverse Process

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.

• The Vertebral Arch is shown in these x-rays.

• Try again!• Choose a new question.

Vertebral Arch

Vertebral Arch

Correct • Yes! (C) is the Dorsal

Spinous Process!

• Here are more examples.

• Try (iv)!• Choose a new question.

Spinous Process

Spinous Process

Incorrect • No (C) is not the

Transverse Process.

• The Transverse Process is shown in these x-rays.

• Try again!• Choose a new question.

Transverse Process

Transverse Process

Incorrect • No, (C) is not the Body

of the Vertebra.

• The Body of the Vertebra is shown in these x-rays.

• Try again!• Choose a new question.

Vertebral Body

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?

– 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? – Atlanto-Occipital Joint– Atlanto-Axial Joint– Occipito-Atlanto-Axial Complex

A

B

Correct • Yes! A is the first

cervical vertebra or C1!

• Here are x-rays of C1

• Try (ii)!• Choose a new question.

C1

Transverse processes or ‘Wings’ of C1

Incorrect • No, A is not C2 which is

the 2nd cervical vertebra!

• These x-rays show C2.

• Try again!• Choose a new question.

C2

C2

Correct • Yes! B is the 2nd cervical

vertebra or C2 which is also known as the Axis!

• These x-rays show the Axis.

• Try (iii)!• Choose a new question.

Axis

Axis

Incorrect • No, B is not also known

as the 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

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.

Atlanto-Occipital

Atlanto-Axial

Occipito-Atlanto-Axial

Incorrect • No, the Atlanto-

Occipital 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.

Atlanto-Axial

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!