Texas Tech Questions Unit 1 Anatomy: Deep Back & Spinal Chord

To insert a needle in the subarachonoid space, the needle must pass through which three ligaments

1. Supraspinpus ligament 2. interspinous ligament 3. ligamenta flava

The intervertebral disc add about ____ the entire length to the vertebral column

1/4

How many pairs of denticulations are there

21 (so they are not found between all dorsal and ventral rootlets)

motion only occurs among ____ vertebrae

24 vertebrae (7 cervical, 12 thoracic, 5 lumbar) sacral and coccygeal are normally fused

The spinal cord is segmented like the vertebral column, but in contrast to the vertebrae, there are only _____ cord segments

31

How many spinal nerves are there?

31 pairs: 8 cervical 12 thoracic 5 lumbar 5 sacral 1 coccygeal

How many segments of the spinal cord are there

31 segments

How many vertebrae are there?

33 vertebrae (7 cervical, 12 thoracic, 5 lumbar, 5 sacral, 4 coccygeal)

In thoracic, lumbar, and sacral regions the spinal nerve come out where?

Below the vertebra of the same #

The subtrapezial plexus of nerves includes:

C3, C4, accessory nerve

The number of vertebrae and the number of spinal cord segments are the same in each region except

Cervical region There are 8 cervical spinal cord segments but only 7 cervical vertebra

Inserting a spinal tap needle in the lumbar region, in the midline, you hear and feel a 'pop' at the needle tip. What structure was perforated to cause the 'pop?'

Crossing the dura mater would cause a "pop" that might be heard while doing a spinal tap.

Where do somatic afferent neurons originate from

Dorsal root and dorsal rootlets

What acts as a shock absorber between the vertebral bodies?

Intervertebral discs

Spinal chord (in an adult) usually ends at the inferior border of

L1

Conus medullaris is the the inferior border of or the superior border of

L1 L2

Spinal chord (in adult) usually ends at the superior border of

L2

The conus medullaris is located at what level

L2

Injection into the spine without injury usually is done below what vertebral level?

L4

What level in the vertebrae should a needle be inserted?

L4 because the spinal cord ends at the bottom of L1 or the top of L2

If disc herniates between L4 and L5 what nerve will be impinged

L5 spinal nerve

A patient is diagnosed as having a venous anomaly of the posterior spinal veins which have enlarged, putting pressure on the spinal cord. In order to expose the veins, the surgeon will have to pass through the skin, subcutaneous tissue, deep back muscles and then, in order, the:

Laminae and ligamenta flava, epidural space, dura, subdural space, arachnoid, subarachnoid space, pia.

In order to expose the spinal cord from the posterior side, it is necessary to remove the

Laminae, spinous process, and ligamenta flavum

Lordosis (anterior sway) is abnormal curvature of what region

Lumbar region

Where is there no disc between vertebrae

No disc between C1 and C2

Where does the dural sac and subarachnoid space end?

S2

Where does the dural sac continue to

S2

What nerve emerges comes out below the T1 vertebra

T1 spinal nerve

c8 nerve emerges above

T1 vertebrae

In an adult, the conus medullaris of the spinal cord is normally positioned at which vertebral body levels:

T12-L2

The spinal cord ends in the lower back as it tapers to form

The conus medullaris

Where do the effort autonomic nerve fibers originate from

The lateral horn of the spinal nerve

A patient is suspected of having bacterial meningitis. A lumbar puncture is performed to remove cerebrospinal fluid (CSF) for analysis. If done properly, the needle used for the tap would penetrate

The needle must pass through the following layers during a lumbar puncture: skin, fat, supraspinous ligament, interspinous ligament, between or through the ligamenta flava, epidural fat and veins, dura, subdural space, and arachnoid.

What is the center of the disc called

The nucleus pulposis

kyphosis is abnormal curvature of what region

Thoracic

A 45-year-old man complained to his physician that the muscles of his upper limb were weak and he felt clumsy while walking. Tests revealed that he had amyotrophic lateral sclerosis (Lou Gehrig's disease), a disease which attacks the neurons of the voluntary motor system. Where would one expect to see atrophic or degenerated nerve cell bodies?

Ventral horn of the spinal cord

The combination of the body and the vertebral arch form

Vertebral canal (vertebral foramen)

The denticulate ligament is

a modification of pia mater

Cervical nerves emerge ______ the vertebrae

above

Trapezius receive motor innervation from

accessory n.

What kind of fibers does the dorsal roots contain

afferent sensory fibers

The dorsal root of the spinal nerve contains what type of nerve fibers

afferent sensory nerve fibers

Discs are designed to

bear weight

In the lumbar spine, the L4 nerve root sleeve exits

below the pedicle of L4 and at the top of the intervertebral foramen

Where is the most inferior disc

between L5 and S1

Denticulate ligaments are not continuously attached to the dural sac instead they appear where

between the dorsal and ventral rootlets

The nerve between c5 and c6 would be called?

c6 nerve

What kind of joint is a disc

cartilaginous joints (symphyses)

Why do women develop temporary lordosis during pregnancy

compensate for the change in their normal line of gravity

Termination of the spinal cord occurs where

conus medullaris

The cauda equina originates from the

conus medullaris

The part of a spinal nerve that supplies the true back muscles and the skin overlying them is the

dorsal primary ramus

What kind of fibers does the ventral roots contain

efferent motor fibers

Where is a safe level for preforming a lumbar puncture

either above or below L4

The center of the vertebral disc (nucleus pulposis) is highly

elastic and compressible

The ligamentum flavum is made of

elastic fibers

Which muscle is innervated by posterior primary rami?

erector spinae

The hiatus of the sacral canal is a normal feature that results from

failure of fusion of the laminae of the 5th sacral segment during development

What extends from the conus medullaris?

filum terminal internum

What is the thread like extension of the pia mater called

filum terminal internum

sympathetic nerve fibers arise from

ganglia ( nerve clusters) which are located outside the spinal cord

The conus medullaris

gives origin to most of the cauda equina

What is the anatomical landmark used to identify L4

iliac crest

What landmark could be used to insert the spinal needle between the 4th and 5th lumbar vertebral spines?

iliac crest

Where do motor neurons have their cell bodies

in the ventral horn of the spinal cord

Because of their structure and interconnections, which veins are especially important in the metastatic spread of cancer?

internal vertebral venous plexus

While moving into a new apartment a student lifting a heavy box of books experiences a sharp pain in his back, radiating down the anterior thigh and medial side of his leg. After several days of misery, he finally goes for treatment and is told that he has a herniated intervertebral disk at the L 4 level which is compressing a spinal nerve where it exits the vertebral column. The point of compression is the:

intervertebral foramen

Ligamenta flava is an elastic ligament which joins the

laminae of adjacent vertebra

Scoliosis is an abnormal ___ curvature.

lateral

Where are the cell bodies of preganglionic sympathetic fibers found

lateral horn of the spinal cord

preganglionic sympathetic neurons originate from

lateral horn of the spinal cord between T1 and L2

If one does a laminectomy (removing the laminae of two adjacent vertebrae) to expose the spinal cord, which ligament must be removed?

ligamenta flava

Cell bodies of the somatic sensory neurons are located

located in the dorsal root ganglia

The denticulate ligaments form

longitudinal shelves that separate the dorsal and ventral rootlets

Herniated disc compress ____ numbered vertebrae of the pair

lower

The accessory nerves provides what kind of innervation

motor innervation to the trapezius

The foramen magnum is an opening in what part of the skull

occipital part of the skill that transmits the spinal cord

The posterior longitudinal ligament is located where

on the posterior surfaces of the vertebral bodies (located in the vertebral canal but not is not penetrated by the needle during a spinal tap)

The ventral primary rami innervate

other muscles including the pectoralis major

The cranial outflow of the autonomic nervous system refers to

parasympathetic nervous fibers

True back muscles are innervated by

posterior dorsal primary rami

erector spinae maintains

posture

A neuron with a cell body in the dorsal root ganglia could convey what type of fibers?

sensory from the skin overlying the trapezius

If dorsal rootlets were avulsed (torn) what nerve fibers would be damaged

somatic afferent nerve fibers

If ventral rootlets were avulsed (torn) which nerve fibers would be damaged?

somatic efferent nerve fibers

cells from the dorsal root ganglia transmit what

somatic sensation from areas like the skin to the CNS

Dorsal and ventral roots fuse together to form what?

spinal nerve

What compartment is the CSF removed from

subarachnoid space

denticulate ligament helps

suspend the spinal cord in the subarachnoid space

Postganglionic sympathetic fibers originate from

sympathetic ganglia (not part of the spinal cord)

Which nerve fibers control the tone of the vasculature and allow for vasoconstriction

sympathetic nerve fibers

It was noted that after the injury the patient's face on the right side was flushed due to dilation of the blood vessels. The lack of vasoconstriction was due to interruption of what fibers somewhere along their course?

sympthetic

The dorsal primary rami innervate

the deep back muscles

Dorsal primary rami innervate

the deep back muscles (erector spinae) and the skin of the back

What is the toughest covering over the spinal cord

the dura mater

the denticulate ligaments extend from what

the lateral surface of the pia

Once a disk herniates, it puts pressure on

the nerve roots or the dorsal root ganglion exiting the intervertebral foramen at or below its level

a slipped disk is the herniation of

the nucleus pulposis

if the sympathetic nervous system was damaged

the peripheral vessels would not be able to constrict

Ventral primary rami supply sensory innervation to

the skin of the anterior trunk and limbs and motor innervation to the skeletal muscles of the neck, trunk, and extremities.

The dorsal primary ramus supplies sensory innervation to

the skin of the back and motor innervation to the true back muscles (deep back muscles)

What is the line connecting the top of the two iliac crests called

the supracristal line (which passes though the spinous process of the L4 vertebra)

C3, C4 and the accessory nerve all innervate

the trapezius

The ventral and dorsal roots of a spinal nerve are made of

the ventral and dorsal rootlets, which come from the spinal cord.

Efferent autonomic nerve fibers travel out of the spinal cord through

the ventral root of the spinal nerve

Why are the internal vertebral venous plexus clinically significant

they are valveless and can serve as a route for metastases

If sympathetic nerve fibers are damaged vessels wont be able to

vasoconstrict. causing them to dialate, producing flush

the sympathetic nervous system is responsible for

vasoconstriction of peripheral vasculature of peripheral vasculature

Spinal nerve divides to form

ventral and dorsal primary rami

the cell bodies of motor neurons are found in the

ventral horn of the spinal cord

Rhomboid muscles and levator scapula are innervated by

ventral primary rami of spinal nerves (Bc they are NOT true back muscles)

Where do somatic efferent neurons originate from?

ventral root and ventral rootlets

Preganglionic sympathetic neurons travel through what

ventral rootlets

Preganglionic sympathetic neurons would be damaged by the avulsion of

ventral rootlets between T1 and L2 (not in cervical regions)

cancerous cells can travel freely in what veins

vertebral veins because they do not have valves

Prostate cancer is diagnosed in an 82 year old male. Thereafter a malignant brain tumor of prostatic origin is found. He subsequently dies. An autopsy reveals tumor sites in the prostate, vertebral column, and brain, but no other organs. By what vascular pathway did the cancerous cells get to the brain:

vertebral venous plexus