Spinal Cord

Question 1

What are the superficial extrinsic muscles of the back? (look at diagrams)

Answer 1

• Trapezius
• Latissimus dorsi
• Levator scapulae
• Rhomboids

Question 2

What are the deep intrinsic muscles of the back? (look at diagrams)

Answer 2

erector spinae

Question 3

What is the role of the trapezius?

Answer 3

Used to tilt and turn the head and neck, shrug, steady the shoulders, and twist the arms.
It elevates, depresses, rotates, and retracts the scapula, or shoulder blade

Question 4

What is the role of the latissimus dorsi?

Answer 4

Extension, adduction, flexion from an extended position, and medial rotation of the shoulder joint.

Question 5

What is the role of the levator scapulae?

Answer 5

elevates and rotates the scapula

Question 6

What is the role of the rhomboids?

Answer 6

Draw in the scapula, pulling it towards the vertebral column and slightly elevate it. Rotate scapula inferiorly

Question 7

What is the role of the erector spinae muscles?

Answer 7

Straighten the back and allows side-to-side rotation

Question 8

What are the main ligaments of the vertebral column and where are they found?

Answer 8

Supraspinous ligaments – connects the tips of spinous processes

Interspinous ligaments – between adjacent spinous processes

Ligamenta flava – between adjacent vertebral arches

Posterior longitudinal ligament – posterior canal

Anterior longitudinal ligament – anterior of body

Question 9

Which ligament is most likely to be injured during a hyper extended neck whip lash injury?

Answer 9

anterior longitudinal ligament

Question 10

What are denticulate ligaments?

Answer 10

Projections of pia mater that anchor the spinal cord to the spinal cord

Question 11

What is filum terminale?

Answer 11

Fibrous tissue that is a modification of pia mater than runs down in the cauda equina

Question 12

What is the conus medullaris?

Answer 12

Where the spinal cord tapers out - around L2

Question 13

What is C1 and C2 called?

Answer 13

1 - atlas

2 -axis

Question 14

What type of joint is the atlanto-occipital?

Answer 14

YES (nodding)

Question 15

What type of joint is the atlanto-axial?

Answer 15

NO (shaking head)

Question 16

Describe the blood supply to the spinal cord

Answer 16

• One anterior and two posterior spinal arteries
• Supplemented by radicular arteries – branches of the intercostal arteries (important during surgery as if damaged can affect spinal nerves)
• Internal and external vertebral venous plexuses

Question 17

What is the significance of the venous plexuses?

Answer 17

The venous plexus provides a path of metastases for cancer from the prostate gland to the brain.

Question 18

How is C7 identified?

Answer 18

first obvious spinous process

Question 19

How is T3 identifed?

Answer 19

Level with the medial end of scapular spine

Question 20

How is T7 identified?

Answer 20

Level with the inferior angle of scapula

Question 21

How is L2 identified?

Answer 21

Level of lowest part of 12th rib

Question 22

How is L4 identified?

Answer 22

Level of iliac crest

Question 23

Why should lumbar punctures not be taken when someone has high intracranial pressure?

Answer 23

The brainstem could fall through the foramen magnum

Question 24

How can the lower sacral nerves by anesthetized alone?

Answer 24

through the sacral hiatus

Question 25

What is scoliosis?

Answer 25

A bend in the spine in the lateral plane (sideways)

Question 26

What is kyphosis?

Answer 26

An exaggerated thoracic curvature

Question 27

What is lordosis?

Answer 27

An exaggerated lumbar curvature (from posterior to anterior curve)

Question 28

Where is backache most common and why?

Answer 28

Lumbar as bears the most weight

Question 29

Where is disc herniation most likely?

Answer 29

L5-S1 due to the angles

Question 30

What is one of the weakest regions of the vertebral column?

Answer 30

lumbar sacral due to sharp turn - lots of disc herniations

Question 31

What are the two types of curvatures?

Answer 31

primary and secondary primary - expected in fetus (thoracic and sacral) secondary - formed later on (lumbar and cervical)

Question 32

What are some features of the cervical vertebrae?

Answer 32

- have holes for vertebral arteries called transverse foramina

Question 33

Give examples of atypical vertebrae

Answer 33

atlas and axis (c1 and c2)

Question 34

Describe the features of c1

Answer 34

- has a facet for dens - has foramen trasnversarium - has no vertebral body - no spinous process - has ligaments e.g. transverse ligament

Question 35

Describe the features of c2

Answer 35

- has a dens (odontoid peg which allows rotation and specific movement)

Question 36

What are some of the ligaments in c1/c2?

Answer 36

cruciate ligament - has superior longitudinal band, inferior longitudinal band and transverse ligament Alar ligament - connect the sides of the dens to tubercles on the medial side of the occipital bone

Question 37

What is the tentorial membrane?

Answer 37

- Covers the odontoid process and ligaments - Continuous with the posterior longitudinal ligament - From the posterior surface of the body of the axis and, attached to the basilar groove of the occipital bone, - As it enters the cranial cavity it becomes continuous with the dura mater

Question 38

How can slipped discs affect nerves?

Answer 38

bilateral posterior herniation can affect entire spinal cord below contralateral herniation can affect individual nerves

Question 39

Where is lumbar puncture taken?

Answer 39

in adults spinal cord ends at L2 in children at L3/4 so usually taken at L3/4 or L4/5 in adults

Question 40

What movements can the cervical spine do?

Answer 40

extension, rotation and bending

Question 41

What movements can the thoracolumbar spine do?

Answer 41

flexion, extension and rotation

Question 42

What are some examples of spinal pathology?

Answer 42

- low back pain - prolapsed disc - spondolysis (degeneration) - spondylitis (vertebrae inflammation)

Question 43

What are some common spinal injuries?

Answer 43

of atlas and axis - little space so a fracture might not kill but if dislodged can impinge on spinal cord and cause instant death

Question 44

What is the significance of the sacral hiatus in terms of anaethesia?

Answer 44

It can be used to anesthetize the sacral nerves only

Question 45

Why should a lumbar puncture not be performed in the presence of high intracranial pressure?

Answer 45

The brainstem could fall through the foramen magnum

Question 46

What things are passed when performing an epidural?

Answer 46

skin, fat, muscle, supraspinous ligament, intraspinous ligament, ligament flavum

Question 47

What things are passed when performing a lumbar puncture?

Answer 47

skin, fat, muscle, supraspinous ligament, intraspinous ligament

Question 48

Why is backache more common in the lumbar region?

Answer 48

spinal angle more sharp

Question 49

What is the filum terminale?

Answer 49

extends down from the conus medullaris (continuous with pia mater)

Question 50

What is the shape of the thoracic and lumbar vertebral body?

Answer 50

T - heart shape | L - kidney shape

Question 51

What are the roles of sheet muscles?

Answer 51

- There are sheet muscles (the oblique muscles, rectus abdominus, transversus abdominus) - These help with flexion - They also help with increasing abdominal pressure (for expulsion, coughing, sneezing, breathing etc.) - The oblique muscles help with side bending as well are rotation.

Question 52

What do erector spinae muscles do?

Answer 52

On the back is the erector spinae muscles – huge column of muscles. They make the spine straight – very complex intrinsic muscles of the spine.

Question 53

Give examples of spinal injuries

Answer 53

* Low back pain * Prolapsed intervertebral disc - sciatica * Spondolysis (degeneration) * Spondylolysis (stress fracture of pars interarticularis) * Spondylolisthesis (forward displacement of vertebra) * Spondylitis (inflammation of vertebrae)