Vertebral Column and Spinal Cord Flashcards
What is the name of the hole in the vertebrae through which the spinal cord travels
Vertebral foramen
Where do spinal nerves leave the spinal canal
Intervertebral foramina
How does the naming of spinal nerves relate to the vertebral levels?
In the cervical spine the spinal nerves emerge superior to their corresponding vertebral levels, hence C8
In the rest of the spine the spinal nerves issue inferior to their corresponding vertebral levels
Give 5 functions of the vertebral column
- Provides centre of gravity
- Attachments for bones
- Attachments for trunk muscles
- Protection and passage of the spinal cord
- Segmental innervation of the body
How does the curvature of the spine change with age
Foetus - Single curvature, C-shaped, primary curvature, faces anteriorly
Adult- 4 curvatures: thoracic and sacral kyphoses and cervical and lumbar lordoses
Cervical develops as baby begins to raise its head. Lumbar lordosis develops as walking
How does the curvature of the spine change with age
Foetus - Single curvature, C-shaped, primary curvature, faces anteriorly
Adult- 4 curvatures: thoracic and sacral kyphoses and cervical and lumbar lordoses
Cervical develops as baby begins to raise its head. Lumbar lordosis develops as walking
In old age the secondary curvature begins to disappear
What is the vertebral body lined with
Hyaline cartilage
How are vertebral bodies linked to each other?
Via intervertebral discs
What are the feature of the vertebral arch?
- Spinous process
- 2x transverse processes
- pedicle
- lamina
- Articular processes X4
Where is the spinous process
Posterior midline
Where are the transverse processes and what is their function?
Found laterally one on each side
Provide attachment for deep back muscles and serve as levers
What is the pedicle?
Part of the neural arch between the body and the transverse process
What is the lamina
Part of the neural arch between the transverse processes and the spinous processes
Where are the articular processes found and what are their functions?
Facets at the junction between the lamina and the pedicle
2 each side 1 above and 1 below, lined with cartilage
Form facet joints which determine movement permitted
Strengthened by ligament flavum
Where are the articular processes found and what are their functions?
Facets at the junction between the lamina and the pedicle
2 each side 1 above and 1 below, lined with cartilage
Form facet joints which determine movement permitted
Strengthened by ligament flavum
Also keep the column aligned
What are the 2 regions of the IVD called?
Central region - nucleus pulposus
Peripheral region - Annulus fibrosus
Describe the structure of the annulus fibrosis
Series of annular bands with varying orientations
Outer bands are collagenous, inner bands are fibre-cartilaginous
Describe the structure of the nucleus pulposus
Jelly like, high osmotic pressure, changes in size throughout the day depending on water distribution
Centrally located in infant but posterior in adult
Can herniate through annulus fibrosis –> slipped disc
How does the nucleus pulposus change with age?
Dehydrates –> decreased height of IV disc –> altered stresses so reactive marginal osteophytes develop
Can also lead to osteoarthritis
What is degenerative annular disease?
Degeneration of the annulus fibrosus which leads to marginal oesteophytosis at the end plates
Seen in thoracolumbar spine of people over 50
What are the symptoms of a posterior herniation of a disc
Pain if compression of spinal nerves
Paralysis if compression of spinal cord
What is the anterior longitudinal ligament?
Strong fibrous band that covers and connects the anterolateral aspects of the vertebral bodies and the IV discs. It is attached to the periosteum of the vertebral bodies but free over the IV discs
It is much stronger than the posterior longitudinal ligament
Extends from the anterior tubercle o atlas to the front part of the upper sacrum
Limits extension
What is the posterior longitudinal ligament?
Extends from the back of the body of the axis to the canal of the sacrum
Becomes narrower as it passes downwards
Has serrated margins which are broadest over the IV discs which they are firmly untied to
Where do you find the ligamentum flavum and what is its action?
Join the laminae of adjacent vertebrae
Where do you find the ligamentum flavum and what is its action?
Join the laminae of adjacent vertebrae. Attached to the front of the upper lamina and the back of the lower lamina
They get thicker as you go down the spine
They are stretched when the spine is flexed
Where do you find the supraspinous ligaments and what do they do?
Connects the tips of the spinous processes from C7 to the sacrum and merge superiorly with the nuchal ligaments at the back of the neck
Where do you find the interspinous ligaments?
They unite the spinous processes along their adjacent boarders
They are thin and relatively weak, they are only well developed in the lumbar region
Where will you find the ligament nuchae?
Attaches to the occipital protuberance and the thoracic spinal ligaments as well as all the spinous processes of the cervical vertebrae
Where will you find the ligament nuchae?
Attaches to the occipital protuberance and the thoracic spinal ligaments as well as all the spinous processes of the cervical vertebrae
Maintains the secondary curvature of the cervical spine. Helps the cervical spine support the head. Is also a site of attachment for trunk muscles
Where do you find intertransverse ligaments
They connect the adjacent transverse processes. They are scattered fibres in the cervical region, fibrous cords in the thoracic region and thin and membranous in the lumbar region
What are the 2 distinguishing features of cervical vertebrae
- Bifid spinous processes
2. Oval transverse foramen in the transverse process
What pass through the transverse foramina?
The vertebral arteries and their accompanying veins except for C7 which transmit only small accessory veins, as they are smaller and sometimes absent in C7
What is the size and shape of the vertebral foramen in the cervical vertebrae?
Large and triangular
What are the distinctive features of the thoracic vertebrae?
- Costal facets for articulation with the head ribs
- The vertebral foramen is circular and smaller than that of the cervical and the lumbar vertebrae
- The transverse processes are long and strong and have facets for articulation with the tubercle of ribs
What are the distinctive features of the lumbar vertebrae?
- Have the largest vertebral bodies, kidney-shaped
- Lack costal facets on the side of the body
- Small, triangular vertebral foramen - larger than thoracic
Which vertebrae is known as the axis?
C2
Which vertebrae is known as the atlas?
C1
What is the articulation of the atlas?
It articulates with the skull (occipital condyles with the superior articular surfaces) above (atlanto-occipital joint) and the axis below (atlanto-axial joint)
What are the structural features of the atlas?
Lacks a body
Lacks spinous process
Is the widest cervical vertebrae
What is the dens on C2
The displaced body of the atlas
What are the features of the axis
- The dens/odontoid process
- Rugged lateral Mass
- Large spinous process
It is the strongest of all the cervical vertebrae
What is the dens held in place by?
The transverse ligament of the atlas
What is referred to as a hangman’s fracture?
Fracture and dislocation of the atlas
What injuries is the cervical spine susceptible to?
Whiplash
Sports e.g. rugby scrums
What injuries is the lumbar spine susceptible to?
Herniation of the L4/5 or the L5/S1 discs
What is referred to as a scoliosis and why might this occur?
A scoliosis is a side to side curvature of the spine
This may be caused by unbalanced muscle tone between the trunk muscles of the left and right of the spine
Which vertebrae is referred to as the vertebra prominens?
C7 as in 70% of people it has the longest spinous process which can be felt in the back of the neck
