Lecture - MSK (Back - Vertebral Column)

Question 1

What are the four functions of the vertebral column?

Answer 1

1. Support - part of the axial skeleton
2. Movement - head and spine
3. Protection - spinal cord
4. Provides attachment for limb girdles (pelvis, pectoral) and truck muscles

Question 2

Structure of the vertebral column:

1. How many mobile and how many fused vertebrae?
2. Classify the vertebrae into theyr groups
3. Is there movement in the spine?

Answer 2

1. 33 vertebra - 24 mobile and 9 fused

2. 7 cervical
12 thoracic
5 lumbar
5 sacral (fused)
4 coccygeal (fused) - can be 3-5 there bc they fuse

3. Yes, spine is described as a flexible rod

Question 3

What are the movements of the vertebral column and what regions do that movement?

Answer 3

Extension and flexion: cervical and lumbar

Lateral flexion: cervical and lumbar

Rotation of the head and neck: Atlanta-axial (C1/C2 -first and second cervical)

Rotation of anything in thoracic region: thoracic (restricted by ribs)

Question 4

Curvature of the vertebral column (the spine)

1. 4 curvatures - what are they?
2. Why do the curves exist?
3. When do these curvatures develop?
4. What’re abnormal curvatures of the spine?

Answer 4

1. Concave curvature forwards
   - thoracic
   - sacral
   Concave curvature backwards
   - cervical
   - lumbar
2. Straight rod = more likely to collapse. Curves means it can take the pressure etc
3. Before birth the whole
   vertebral column is concave
   forwards (“primary”
   curvature, kyphosis - just a C shape)

"Secondary" curvatures
(lordosis) develop in cervical
and lumbar regions as the
infant starts to lift up its head
and to stand

So have primary curvature in thoracic and sacral region. The cervical and lumbar curvatures are secondary. So lumbar and cervical lordosis are normal

4. The curvatures are determined by shape of vertebral bodies & discs. SCOLIOSIS is another curve - lateral curve of the verterbral coloum. Normally it’s in the saggital plane but if it starts to go laterally, it is called scoliosis - occurs more commonly in thoracic and lumbar region (can be congential or neuromuscular or idiopathic). KYPHOSIS is the thoracic ‘hunchback’ deformity - ssed for describing overeaxxgerated primary curve. Kyphosis can be normal (prev slide) but it is seen as overexaggerated back curve. It occurs as we get older. Most common in older females

Question 5

What does a typical vertebra look like?

Answer 5

It has a body, a vertebral (neural) arch, pedicle (bw body and transverse process), has lamina (bw transverse and spinous process) and facets - for articulation

Question 6

Cervical vertebrae:

1. What does it look like? Describe the body, arch, vertebral foramen
2. What are atypical cervical vertebrae?
3. Cervical soine injury - what happens? What should you do? How to check on X-ray?

Answer 6

1. Body: small, delicate and saddle-shaped

Arch: spinous process is short and bifid (except C7 - it is referred to as the vetebra prominens because it has a lonher and larger spinous process than other cervical vertebrae. The spinous process if not usually bifid). The transverse process - in it, it has transverse foramen. No other section has a transverse foramen other than cervical - it’s for the verteral artery

Vertebral foramen: large and triangular-shaped. It has to accomodate for fatter spinal cord so more axons and larger ()

2. Atlas (C1) and axis (C2). Atlas articulates with occipital condyles above and with axis below. The vertebral body of atlas is stolen by axis (it’s called dens - go see the diagram). This dens is held in place by strong transverse ligament. The pivot allows head and atlas to rotate on axis (saying NO)
   - So axis articulares with anterior arch of atlas and is held there by strong ligameents (like transverse ligaments) and cruciform ligaments - cross shaped just posterior to transverse ligament
3. • e.g. a fall from a height,
   diving, high speed car crash
   • often unconscious
   • stabilise neck (otherwise the shifted bones go an squash the spinal cord)
   • must see all 7 vertebrae
   on neck X-rays (see the distances bw the processes and see the bodies of the vertebrae)

Question 7

What does the atlanto-occipital joint look like?

Answer 7

Look at slide 15

This allows you to say yes

Question 8

Thoracic vertebrae:

1. What does the typical vertebrae look like?
2. What passes through the intervertebral foramen?

Answer 8

1. Has all the things - body, arch, foramen (vertebral canal), it has pedicles but they have vertebral notches and those form INTERVERTEBRAL FORAMEN when you line them up in the spine. There are superior and inferior articular processes and the joint between them is the Z-JOINT. Also, have inferior and superior costal facets for the head of the rib and facets on the transverse processes for the tubercle of the ribs.
2. Provides a gateway for the
   - spinal nerve,
   - segmental spinal artery
   - spinal veins
   to enter or leave the vertebral
   canal

Question 9

Lumbar vertebrae:

1. What do they look like?
2. Difference between lumbar and thoracic vertebrae? What use is it?

Answer 9

1. Body: heavily built for weight-bearing (large vertebral body)
   Arch: spinous process is horizontal and short (thoracic sorta goes down)
   Vertebral foramen: large and triangular (bc sacral plexus)
2. There is space between adjacent lamina in the lumbar vertebrae (good for getting samples of fluid or by lumbar puncture). Take sample of CSF here bc safe area since end of spinal cord

Question 10

Sacrum

1. What constitutes it?
2. What do the anterior and posterior sacral foramina look like?
3. What can you say about the sacral canal?

Answer 10

1. 5 fused sacral vertebae
2. Go look at diagram
3. Canal continues into the sacrum and then called sacral canal - opening at the bottom (sacral haitus) - anasthesia given through the sacral haitus sometimes

Question 11

What are the three vertebral connections?

Answer 11

1. Intervertebral discs (fibrocartilage connection)
2. Intervertebral joints (synovial facet joints)
3. Ligaments (fibrous connections)

NB: 􀀁bony connections􀀂 - e.g. connections between sacral &
coccygeal vertebrae (fused)

Question 12

Intervertebral discs:

1. What two things is it made of?
2. In what region are the discs the largest? Account to how much of the height of the vertebral column?
3. What is the function of the discs?
4. What is intervertebral discs props and where is it most common?

Answer 12

1. Nucelus pulposus (shock absorber ‘gel’-like) and annulus fibrosis (concentric layers of fibrocartilage).
2. • largest in lumbar region
     - account for ~25% of height
     of vertebral column
3. Function- resist compression, binds vertebrae, absorbs shock, resists motion and provides stability and mobility
4. Once the annulus fibrosis gets weak, nucleus purposes comes out. Can also happen in central aspect. Squashes nerves when goes posterolaterally (usually goes in this direction). May cause sciatica. L4/5 and S1/5 are usually the ones that get the prolapse. The nerve it squashes is the last one so L4/5 means L5 spinal nerve will get squashed

Question 13

Intervertebral joints between articular processes (z-joints)

1. What type are they?
2. What do they look like in each of the cervical, thoracic and lumbar?
3. Orientation of the articular
   surfaces dictate what?
4. Just go over the movements of the vertebral column again pls

Answer 13

1. Plane synovial
2. Look at slide 31
   Cervical: in transverse plane so can do flexion and extension
   Thoracic: In coronal plane so can rotate early and the only thing that rotates that is ribs
   Lumbar: In sagittal plane so can’t rotate and can only do flexion and extension here
3. Movements of the vertebral
   column- Flexion, extension-C +L; lateral flexion- C+L, rotation
   head- AA, C1,2, trunk rotation- T

Question 14

Go through the ligaments

1. Between vertebral bodies
2. Between vertebral laminae
3. Between spinous processes
4. What is ligament nuchae?

Answer 14

1. • Anterior longitudinal ligament
   • Posterior longitudinal ligament
2. • Ligamentum flavum
3. • Interspinous ligament
   • Supraspinous ligament
4. – continuation of
   supraspinous ligament
   between C7 and base of
   skull. Gives attachment to muscles in neck, more support, etc

Question 15

Back muscles (go onto slides to fully understand this):

1. What are muscles in the superficial (extension) group?
2. What are muscles in the deep (intrinsic) muscles
3. What are muscles from other regions that cause flexion or extension of the trunk?

Answer 15

1. Trapezius, Rhomboids and Latissimus dorsi
2. Erector spinae (spinalis, longissimus and illiocostalis)
   - semispinalis
   - multifundus
3. To go from flexion to neutral: rectus abdominis, psoas major.
   To go from extension to neutral: Erector spinae, multifundus, semispinalis, thoracic annnnnd gluteus Maximus

Question 16

What does sternocleidomastoid do?

Answer 16

• lateral flexion of neck &
  rotation of head (unilateral)
• flexion of neck (bilateral)