ANATOMY OF THE SPINAL CORD

Question 1

The_______________ is a long cylindrical structure, covered by meninges, flattened anteroposteriorly & occupies most of the cranial 2/3rd of the vertebral canal.

Answer 1

spinal cord

Question 2

The extent of the spinal cord from the medulla oblongata at the foramen magnum to terminate caudally (distally) as the ____________ in the adult at L1 level

Answer 2

conus medullaris

Question 3

In a 3 month-old fetus, it extends the whole length of the vertebral canal at level of __ vertebra

Answer 3

S2

Question 4

In a 3 month-old fetus, it extends the whole length of the vertebral canal at level of S2 vertebra, but because of greater growth in length of the vertebral column than in the spinal cord, the ___________ lies at the level of L2 vertebra at birth & at lower limit of L1 or upper limit of __ at the age of 20.

Answer 4

conus medullaris, L2

Question 5

Beyond the conus medullaris, a prolongation of pia mater extends as a thin cord- ___________

Answer 5

Filum terminale

Question 6

The Filum terminale is attached to the posterior aspect of the _st coccygeal segment.

Answer 6

1st coccygeal segment.

Question 7

In adults, the spinal cord measures __ - __ cm long (from foramen magnum to level of L1/L2 vertebra).

Answer 7

42-45 cm

Question 8

FUNCTIONS

1. The spinal cord is the major _________ & ____________ between the body & the brain.
2. The spinal cord carries messages between the CNS and the rest of the body, and mediates numerous spinal reflexes such as the _________

Answer 8

1. reflex center & conduction pathway

2. knee-jerk reflex.

Question 9

_______ ligaments are 2 flattened bands of pial tissue that attach to the spinal dura with about 21 teeth

Answer 9

Dentate ligaments

Question 10

_________ is a pial filament extending from the conus medullaris to the end of the dural sac , with which it fuses

Answer 10

Filum terminale

Question 11

_________ provide the strongest anchorage & fixation of the spinal cord to the vertebral canal

Answer 11

Spinal nerve roots

Question 12

There are 31 pairs of spinal nerves which arise from each side of the spinal cord namely:
_ cervical
__ thoracic
_ lumbar
_ sacral
_ coccygeal
The spinal nerves contain both motor & sensory fibres

Answer 12

8 cervical
12 thoracic
5 lumbar
5 sacral
1 coccygeal

Question 13

The part of the spinal cord from which a pair of spinal nerves arises is called a _____ segment

Answer 13

spinal segment

Question 14

Dorsal root contain _______ nerve fibers with a Dorsal root ganglion

Answer 14

Sensory

Question 15

Ventral root contain ______ and Autonomic nerves fibers

Answer 15

Motor

Question 16

The Dorsal & Ventral roots unite at the _________ foramen to form the spinal nerve

Next, Having left the vertebral canal,

spinal nerves divide into _____ & _____ rami, each of which carry motor & sensory nerves.

Answer 16

Intervertebral foramen,

Dorsal & Ventral rami,

Question 17

1. Spinal nerves C1 to C7 exit _____ the pedicle of the corresponding vertebrae
2. ALL other spinal nerves exit _____ the pedicles of the corresponding vertebrae
3. the C8 nerve passes _____ the pedicle of C7 (there is noC8 vertebra)
4. L5 nerve passes under the pedicle of the L5 vertebra.

Answer 17

1. above
2. below
3. under
4. L5

Question 18

The lumbar, sacral & coccygeal roots that exit below the conus at L1/L2 are contained within the dura as far as its lower limit at S2 & are called the ____________

Answer 18

Cauda Equina

Question 19

The lumbar & sacral roots below the end (termination) of the cord at vertebral level L2, continue as a leash of nerve roots termed the _____________

Answer 19

Cauda equina

Question 20

The cross section of the spinal cord include:

Answer 20

1. the Central canal
2. H-shaped Grey matter
3. white matter

Question 21

The cross section of the spinal cord include:

1. the C___ral canal
2. H-shaped Gr_y matter
3. wh_te matter

Answer 21

1. Central
2. Grey
3. white

Question 22

The _________ which is the center ( also contains csf) is surrounded by a H-shaped _________, which is in-turn surrounded by the ________ which is made up of the long ascending and descending fibers

Answer 22

1. Central canal
2. grey matter
3. white matter

Question 23

THE ASCENDING TRACTS: include the following:

Answer 23

1. the Posterior & Anterior Spinocerebellar tracts.
2. the Lateral & Anterior Spinothalamic tracts.
3. the Posterior Columns comprise a medial & lateral tracts , termed respectively:
   - the Fasciculus Gracilis (of Goll) &
   - the Fasciculus Cuneatus (of Burdch).

Question 24

THE ASCENDING TRACTS: include the following:
1. the Anterior & Posterior__________ tracts.

2. the Lateral & Anterior ________ tracts.
3. the Posterior Columns comprise a medial & lateral tracts , termed respectively:
   - the Fasciculus _______ (of Goll)

&

-the Fasciculus _______ (of Burdch).

Answer 24

Spinocerebellar,

Spinothalamic

Gracilis and Cuneatus

Question 25

The Fasiculus Gracilis abd Cuneatus are concerened with ______ touch and pro____eption

Answer 25

Fine touch, propioception

Question 26

the Anterior & Posterior Spinocerebellar tracts ascends on the same side of the cord & enter the _________ through the inferior & superior cerebellar peduncles respectively

Answer 26

cerebellum

Question 27

THE LATERAL & ANTERIOR SPINOTHALAMIC TRACTS is concerned with P_in and Tem_erature

Answer 27

Pain and Temperature

Question 28

The descending Tracts include the following:

Answer 28

1. the Pyramidal (Lateral Cerebrospinal or Crossed motor ) tract. 2. the Direct Pyramidal (Anterior Cerebrospinal or Uncrossed motor) tract.

Question 29

The descending Tracts include the following: 1. the P__amidal (Lateral Cerebrospinal or Crossed motor ) tract. 2. the Di_ect Pyramidal (Anterior Cerebrospinal or Uncrossed motor) tract.

Answer 29

1. Pyramidal | 2. Direct

Question 30

THE PYRAMIDAL (LATERAL CEREBROSPINAL or CROSSED MOTOR TRACT The motor pathway starts at the ____________________, crosses (decussates) in the medulla, then descends in the pyramidal tract on the contralateral (opposite) side of the cord

Answer 30

Pyramidal cells of the motor cortex

Question 31

. THE DIRECT PYRAMIDAL (ANTERIOR CEREBROSPINAL or UNCROSSED MOTOR) TRACT Is a small motor tract descending without c___sing at the medulla (no medullary decussation).

Answer 31

crossing

Question 32

The pyramidal tract __________in the medulla while the Direct tract does not _____ at the medulla

Answer 32

crosses cross

Question 33

ARTERIES OF SPINAL CORD AND NERVE ROOTS The arteries supplying the spinal cord are branches of the: 1. ve__bral 2. asc_nding and d_ep cervical 3. i_tercostal 4. lu_bar & 5. lateral sa_ral arteries.

Answer 33

1. vertebral 2. ascending and deep cervical 3. intercostal 4. lumbar & 5. lateral sacral arteries

Question 34

ARTERIES OF SPINAL CORD AND NERVE ROOTS The arteries supplying the spinal cord are branches of the: .

Answer 34

1. vertebral 2. ascending and deep cervical 3. intercostal 4. lumbar & 5. lateral sacral arteries

Question 35

The arteries of the spinal cord are the: 1. __________________ (ASA) 2. _________________ (PSA) The veins of the spinal cord are the: 1. Anterior ____ vein 2. Paired ______ spinal vein

Answer 35

1. Anterior spinal artery 2. Paired Posterior spinal arteries 1. Anterior spinal vein (three) 2. Posterior spinal vein (three)

Question 36

The anterior & posterior spinal arteries can supply only the short superior part of the spinal cord, by themselves. The circulation to much of the spinal cord is from the _____________ & ________ arteries

Answer 36

segmental medullary & radicular

Question 37

the great ________ segmental artery (of Adamkiewicz), which is on the left side in about 65% of people, reinforces the circulation to 2/3rd of the spinal cord, + the lumbosacral enlargement.

Answer 37

anterior

Question 38

___________ reflex Is a monosynaptic & ipsilateral muscle stretch reflex. Is incorrectly called a deep tendon reflex. Has an Afferent & an Efferent limb, like all reflexes

Answer 38

MYOTACTIC REFLEX

Question 39

SPINAL CORD INJURY 1. Complete transection: - _____ of movement (muscle paralysis) & all sensation below the level of the injured segment. the paralysis is at 1st flaccid, then becomes spastic after a few weeks & bladder & rectal sphincter control is lost,

Answer 39

loss

Question 40

what is Complete transection?

Answer 40

loss of movement (muscle paralysis) & all sensation below the level of the injured segment

Question 41

. Hemisection (Brown-Sequard syndrome): there is -paralysis & loss of touch & ki__esthetic sense below the level of the lesion on the same side loss of pain & temperature sensation on the opposite side (because of interruption of the crossed anterolateral tract

Answer 41

kinaesthetic

Question 42

What is Hemisection (Brown-Sequard syndrome?

Answer 42

paralysis & loss of touch & kinaesthetic sense below the level of the lesion on the same side loss of pain & temperature sensation on the opposite side (because of interruption of the crossed anterolateral tract

Question 43

Central cord syndrome, commonly due to _____injury (without transection) following a sudden hyper-extension of the cervical spine

Answer 43

crush

Question 44

What is Central cord syndrome

Answer 44

it is commonly due to crush injury (without transection) following a sudden hyper-extension of the cervical spine

Question 45

in Central cord syndrome there is: 1. flaccid paralysis (lower motor neurone) & 2. loss of pain & temperature sensation in the upper limbs (due to anterior horn damage and interruption of the more deeply placed cervical fibres of the anterolateral tracts). 3. The lower limbs may show spasticity if the lumbar fibres of the lateral corticospinal tract are involved (sacral fibres are more superficial).

Answer 45

1. flaccid paralysis (lower motor neurone) & 2. loss of pain & temperature sensation in the upper limbs (due to anterior horn damage and interruption of the more deeply placed cervical fibres of the anterolateral tracts). 3. The lower limbs may show spasticity if the lumbar fibres of the lateral corticospinal tract are involved (sacral fibres are more superficial).

Question 46

Anterior spinal artery syndrome: The posterior ______columns (and therefore touch sensation) remain intact, but most of the rest of the cord below the level of the lesion is affected with loss of all motor & sensory functions, except perhaps for the “sacral sparing”.

Answer 46

white

Question 47

Anterior spinal artery syndrome:

Answer 47

The posterior white columns (and therefore touch sensation) remain intact, but most of the rest of the cord below the level of the lesion is affected with loss of all motor & sensory functions, except perhaps for the “sacral sparing”.

Question 48

The spinal cord is derived from the caudal part of the ______ tube.

Answer 48

neural

Question 49

The spinal cord weighs about __ grams, making up _% of the adult brain weight.

Answer 49

30grams , 2%