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 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  Canine No, the Thoracic Inlet is not the Caudal boundary of the Thorax. The Caudal boundary is the Diaphragm. Try again! Choose a new question.

 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  Try again! Choose a new question. 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  Try again! Choose a new question. 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 x-ray. Try (iv)! Choose a new question. Feline

 Incorrect  Try again! Choose a new question. 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  Try again! Choose a new question. 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 (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  Feline Yes! The Diaphragm attaches to the Lumbar Vertebrae and Last Sternebra or Xiphoid. Try (ii)! Choose a new question.

 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 Ribcage Q3 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. 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. 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? (ii) What is B? (iii) What is C? Vertebral Foramen Obturator Foramen Intervertebral Foramen (ii) What is B? Dorsal Spinous Process Vertebral Arch Transverse Process (iii) What is C? Body of Vertebra (iv) Do you know where in the spine this vertebra is from? How can you tell? Answer. Typical Vertebra Q4 C B A

 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 C1 or Atlas Vertebral Foramen

 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? (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. Atlas Wings of Atlas

 Correct  Try Clinical Considerations Q6! Choose a new question. 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-Axial Atlanto-Occipital 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 Try (ii)! Choose a new question. 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!