Back, Vertebral Column & Spinal Cord

Front 1

How many vertebrae does a newborn have? How many vertebrae does an adult have?

Back 1

Child - 33 (5 sacral, 4 coccygeal)

Adult - 7 cervical, 12 thoracic, 5 lumbar, 1 sacrum, 1 coccyx

Front 2

Describe intervertebral discs.

Back 2

- Separate the vertebrae

- Made of fibrocartilage

-Act as shock absorbers

-Composed of an inner nucleus pulpous, and a tough outher annulus fibrosus

Front 3

What is the main purpose of intervertebral foramina?

Back 3

To allow passage of spinal nerves (31 pairs) from the spinal cord to the body.

Front 4

Describe the curvatures of the back. Where are they? Which way do they go? How do they arise?

Back 4

Primary: Thoracic and sacral. Concave anteriorly. Mimic the fetal position.

Secondary: Cervical and Lumbar. Convex anteriorly. Develop in response to infant holding head erect and beginning to walk.

Front 5

What is kyphosis?

Back 5

An abnormal increase in the posterior curvature of the spine (hunchback), particularly in the thoracic region.

Front 6

What is lordosis?

Back 6

An abnormal increase in the anterior curvature of the spine that may be caused from a weakening of the anterior abdominal muscles from weight gain or pregnancy.

Front 7

What is scoliosis?

Back 7

An abnormal lateral curvature. May be caused by an absent half of a vertebra, a wedge-shaped vertebra, or an uneven weakness in the musculature.

Front 8

List and locate the 5 major ligaments of the vertebral column.

Back 8

Anterior Longitudinal Ligament - runs in front of the vertebral bodies from occipital to sacrum.

Posterior Longitudinal Ligament - runs on the posterior aspect of the vertebral bodies inside the vertebral canal. Runs from C2 to sacrum.

Supraspinous Ligaments - attaches the tips of adjacent vertebral spines (links with interspinous to form ligamentum nuchae in the cervical region)

Ligamentum flavum - connects lamina of adjacent vertebrae.

Interspinous ligaments - connect adjacent vertebral spines.

Front 9

List the major ligaments of the vertebral column form posterior to anterior.

Back 9

Supraspinous ligament, interspinous ligament, ligamentum flavum, posterior longitudinal ligament, anterior longitudinal ligament

Front 10

Why are the vertebral venous plexuses important?

Back 10

They drain into the vertebral, intercostal, lumbar, and lateral sacral veins. May provide a route for the spread of infection or metastasis to the vertebrae, spinal cord, and/or brain.

Front 11

Which muscle groups of the back comprise the extrinsic muscles?

Back 11

Superficial - trapezius, latissimus dorsi, levator scapulae, rhomboids major and minor.

Intermediate - Serratus posterior superior, serratus posterior inferior

Front 12

Which muscle groups of the back comprise the intrinsic muscles?

Back 12

Deep - Erector spinae group (spinalis, longissimus, and iliocostalis)

Front 13

What is the auscultatory triangle? What are its boundaries?

Back 13

The site on the back where breath sounds may be most easily heard with a stethoscope.

Boundaries: Latissimus dorsi, trapezius, and the medial border of the scapula. The rhomboid major forms the floor.

Front 14

What is the lumbar triangle?
What are its boundaries?

Back 14

Is the site where pus may emerge from the abdominal wall.

Boundaries: Latissimus dorsi, the posterior border of the external oblique muscle, and the iliac crest.

Front 15

Where does the spinal cord terminate?

Back 15

L1/L2

Front 16

Which three meninges surround the spinal cord?

Back 16

From superficial to deep:
Dura mater
Arachnoid mater
Pia mater

Front 17

Where is the CSF protecting the spinal cord located?

Back 17

Subarachnoid space

Front 18

What is the conus medullaris?

Back 18

The terminal end of the spinal cord.

Front 19

What is the filum terminale?

Back 19

A terminal extension of the pia mater that extends from the conus (end of spinal cord) to the posterior surface of the coccyx.

Front 20

What type of information is carried by ventral roots? How about by dorsal roots?

Back 20

Ventral = motor

Dorsal = sensory

Front 21

What is the cauda equina?

Back 21

A vertical leash of nerves around the filum terminale, formed by the roots of the lumbar and the sacral nerves below the level of the termination of the cord.

Front 22

Describe the dividing and rejoining that occurs as nerve roots exit the spinal cord.

What kind of info is being carried in each structure?

Back 22

The dorsal and ventral nerve roots pass through the intervertebral foramina and then unite to form spinal nerves. The spinal nerve then divides into a large ventral ramus and a smaller dorsal ramus.

Dorsal roots = sensory info
Ventral roots = motor info
Spinal nerves = both
Ventral rami = both
Dorsal rami = both

Front 23

Describe the superior and inferior anatomy of the dura mater.

Back 23

Superior - continuous with the meningeal layer of dura covering the brain

Inferior - ends on the filum terminale at the level of the lower border of the second sacral vertebra.

*External membrane of dense fibrous tissue. Encloses the spinal cord and cauda eqiuna.

Front 24

Describe the superior and inferior anatomy of the arachnoid mater.

Back 24

Superior - continuous through the foramen magnum with the arachnoid covering the brain.

Inferior - it ends on the filum terminale at the level of the lower border of the second sacral vertebra.

*It continues along the spinal nerve roots, forming small, lateral extensions of the subarachnoid space.

Front 25

Describe the superior and inferior anatomy of the pia mater.

Back 25

Superior - thickened on each side between the nerve roots to form the denticulate ligament, which passes laterally to adhere to the arachnoid and the dura. The pia extends along each nerve root as far as the spinal nerve.

Inferior - it is a terminal elongation off the lower end of the spinal cord called the filum terminale.

Front 26

What are the boundaries of the intervertebral foramina?

Back 26

Above and below - the pedicles of adjacent vertebrae.

In front - part of the vertebral body and the intervertebral disc

Behind - the articular processes and the joint between them

Front 27

Describe spina bifida.

Back 27

Results when the vertebral laminae fail to fuse.

Usually presents as lack of a spinous process.

Most common in the lower lumbar or sacral vertebral levels.

Front 28

Where is the best place for a lumbar puncture?

Back 28

The vertebral canal either above or below the fourth lumbar spine.

Front 29

What anatomic structures does a needle need to pass through during a spinal tap?

Back 29

Skin, fascia, interspinous ligament, ligamentum flavum, fatty tissue and the internal vertebral venous plexus, dura mater, and arachnoid mater.

Front 30

Where is a disc herniation most likely to occur?

Back 30

Most common in the lower lumbar and the lower cervical regions.

Usually occurs posterolaterally within the vertebral column and just lateral to the thin posterior longitudinal ligament, which the annulus fibrosus is weak.

Front 31

What are the parts of a typical vertebra?

Back 31

-Body
-Seven processes: spinous process, two transverse processes, four articular processes
-Two pedicles
-Two laminae

Front 32

What is significant about C1, the atlas?

Back 32

It doesn't have a body, nor a spinous process. Ring-shaped with paired lateral masses to bear the weight of the cranium.

Front 33

What is significant about C2, the axis?

Back 33

Has a blunt, tooth-like dens (odontoid process) that projects superiorly from its body.

Front 34

What are the four normal movements of the vertebral column?

Back 34

1. Flexion (touch your toes)
2. Extension (lean backwards)
3. Lateral flexion (run hand down side of leg)
4. Rotation

Front 35

What are the formed by the articulating processes of adjacent vertebrae?

Back 35

Zygapophyseal (facet) joints

Front 36

What are the joints of the vertebral body called?

Back 36

Symphyses (secondary cartilaginous joints) - designed for weight bearing and strength

Front 37

What connect the articulating surfaces of adjacent vertebrae?

Back 37

IV discs and ligaments

Front 38

Describe the spinal dural sac.

Back 38

A long tubular sheath within the vertebral canal.

Adheres to the margin of the foramen magnum of the cranium, where it is continuous with the cranial dura mater.

Ends in the filum terminale externa.

Front 39

What is the difference between the filum terminale interna and the filum terminale externa?

Back 39

Interna - pia mater extension within the dural sac

Externa - formed by the dual sac and the film terminale interna, anchors the spinal cord and meninges to the coccyx.

Front 40

Describe the two sources of the spinal cord blood supply.

Back 40

Anterior Spinal Artery - arises from the vertebral arteries, unite to form a single artery which travels midline of the spinal cord and supplies the anterior 2/3 of the spinal cord.

Posterior Spinal Arteries - arise from the vertebral arteries and travel just posterior to the dorsal horn of the spinal cord (bilateral) and together supply the remaining 1/3 of the spinal cord.

Front 41

The anterior and posterior spinal arteries extend caudally to supply the spinal cord, but cannot reach the lumbosacral. What does?

Back 41

Radicular arteries, they are branches off of the posterior intercostal arteries. The main player is the great radicular artery.

Front 42

Each spinal nerve gives rise to anterior and posterior rami. Rami innervate where?

Back 42

Dorsal Rami - to deep back muscles / skin

Ventral Rami - to trunk / limbs

Front 43

Where are the intervertebral foramen formed?

Back 43

Between each vertebral arch and the adjacent zygapophyseal joint.

Front 44

Explain where the spinal nerves exit?

Back 44

C1-C7: exit above the corresponding vertebra

C8: exits between C7 and T1

All over nerves: exit below the corresponding vertebra (ex. T1 spinal nerve exits below the T1 vertebra)

Front 45

What is a myotome?

Back 45

Consists of all the striated muscle fibers innervated by a given cord segment.

Front 46

Why is a dermatome?

Back 46

The area of skin innervated by a given spinal cord segment.

Front 47

List 4 ways a cervical vertebrae can be distinguished from the others.

Back 47

1. Foramen in the transverse processes.
2. Small body
3. Small transverse processes
4. Flat, horizontal articular processes

Front 48

List 4 ways a thoracic vertebrae can be distinguished from the others.

Back 48

1. Medium body
2. Articulations for ribs on body and transverse processes.
3. Medium transverse processes
4. Flat and vertical articular processes.

Front 49

List 3 ways a lumbar vertebrae can be distinguished from the others.

Back 49

1. Large body
2. Large transverse processes
3. Stout, cuplike articulate processes

Front 50

Describe the articular processes of the cervical vertebrae and explain how their shape affects their movement.

Back 50

Flat, nearly horizontal processes allow for a wide range of flexion and rotation.

Front 51

Describe the shape of the articular processes of the thoracic vertebrae and explain how their shape affects their motion.

Back 51

Flat and nearly vertical, allows for forward and backwards flexion but little rotation, prevent slipping.

Front 52

Describe the shape of the articular processes of the lumbar vertebrae and explain how their shape affects their motion.

Back 52

Stout, cup-like articulations allow for rotation and provide significant stability.