Imaging the spine - 24/10/18 Flashcards
What do X-rays show?
Bone Outlines
What do CT scans show?
Bone outlines in more detail and some soft tissue structures e.g. lumbar disc
What do MRI scans show?
Bone outlines in less detail but shows bone marrow, discs, ligaments and the spinal cord and nerves
What are the 3 curves of the spine?
Cervical lordosis
Thoracic kyphosis
Lumbar Lordosis
Which vertebraes all have the same anatomy?
C3-C7
all 12th thoracic
5 lumbar
What is the anatomy of most of the vertebrae?
A vertebral body Posterior arch 2 pedicles 2 Laminae 1 spinous process 2 transverse processes
Where does the neural foramen lie?
Inferior to the pedicle
How do the articular processes project?
Superiorly and inferiorly between the pedicles and laminae
Forming the facet joints
How are normal anatomincal features depicted?
Lateral view
Which vertebrae has no vertebral body?
C1`
What forms c1?
Anterior and posterior arches united by two large lateral masses, articulate with the occipital bone and C2`
What does C2 have?
An odontoid process which projects superiorly into C1 forming a joint with its anterior arch
When is CT used to image spinal trauma?
X-ray shows break but more detail is required
When X-ray is normal but there is a high clinical suspicion of break
What do ligaments do?
Tether vertebrae together and are responsible for spinal stability
How are ligaments assessed?
Not seen on x-ray or CT
Seeing normal vertebral alignment on these tests implies intact ligaments and stable spine
Abnormal alignment on x-ray implies ligament damage
How are ligaments seen directly?
MRI
Normal ligaments are black
Damaged ligaments are light
Why is MRI used to image spinal trauma?
Provide detail of the spinal ligaments
Show soft tissue abnormality
What kinds of soft tissue abnormality can be seen on MRI?
Acute prolapsed intervertebral disc
Epidural Haematoma
Spinal cord damage
What X-ray and CT features suggest tumour?
Bone destruction
vertebral collapse
Bone sclerosis
What is seen on MRI with tumours?
Early - bone marrow infiltration
Late - extradural mass and spinal cord compression
What do the intervrtebral discs do?
Cushion body from spinal stress
What are healthy discs filled with?
Water
What can happen when discs dehydrate?
Herniation through disc lining into the spinal canal
What can a herniated disc cause?
Spinal nerve compression
Sciatica
Can intervertebral discs be seen on X-ray?
No
What do CT and mRI show in discs?
Disc prolapse
Which imaging shows the spinal cord?
MRI
