Sensory neuron fibers are classified into four major groups primarily by:

A. Neurotransmitter and origin
B. Size and function
C. Color and trajectory
D. Root level and side

B. Size and function

Largest diameter, proprioception:

A. A-delta
B. C
C. A-beta
D. A-alpha

D. A-alpha

Proprioception, light touch, deep touch

A. A-delta
B. C
C. A-beta
D. A-alpha

C. A-beta

Pain, cold temperature, itch

A. A-delta
B. C
C. A-beta
D. A-alpha

A. A-delta

Smallest diameter, warm temperature, itch

A. A-delta
B. C
C. A-beta
D. A-alpha

B. C

Compared with smaller unmyelinated fibers, larger myelinated fibers generally conduct:

A. More slowly
B. More rapidly
C. Only centrally
D. Intermittently

B. More rapidly

The cell bodies of primary sensory neurons are located in the:

A. Ventral horn
B. Dorsal root ganglion
C. Spinothalamic tract
D. Posterior column nucleus

B. Dorsal root ganglion

Primary sensory neurons are termed pseudounipolar because they have:

A. Two dendrites, no axon
B. One axon, one dendrite
C. One process splitting in two
D. Many peripheral branches only

C. One process splitting in two

In a pseudounipolar sensory neuron, one process extends peripherally while the other projects into the:

A. Cerebellar cortex
B. Spinal cord gray matter
C. Internal capsule
D. Ventral root ganglion

B. Spinal cord gray matter

A band of numbness across the chest corresponds to sensory loss from one spinal root level. This region is called a:

A. Myotome
B. Sclerotome
C. Dermatome
D. Neurotome

C. Dermatome

The primary axons of the posterior column pathway are best described as:

A. Small, unmyelinated pain fibers
B. Large, myelinated sensory fibers
C. Thin, autonomic postganglionics
D. Medium, motor efferent fibers

B. Large, myelinated sensory fibers

Posterior column fibers first enter the spinal cord through the:

A. Ventral root
B. Lateral horn
C. Dorsal root
D. Anterior commissure

C. Dorsal root

After entering the spinal cord, first-order posterior column axons ascend in which location before synapsing?

A. Contralateral lateral funiculus
B. Ipsilateral posterior column
C. Ventral corticospinal tract
D. Spinothalamic anterolateral tract

B. Ipsilateral posterior column

A lesion interrupts first-order posterior column fibers before they synapse. These axons normally ascend to the:

A. Thalamus in pons
B. Cerebellum in midbrain
C. Medulla nuclei
D. Internal capsule

C. Medulla nuclei

Which statement correctly describes the organization of the posterior column pathway?

A. One tract, one nucleus
B. Two tracts, two nuclei
C. Two tracts, one nucleus
D. One tract, two nuclei

B. Two tracts, two nuclei

Sensory fibers carrying proprioception from the lower limb ascend in which fasciculus?

A. Fasciculus cuneatus
B. Lateral spinothalamic tract
C. Fasciculus gracilis
D. Anterior spinocerebellar tract

C. Fasciculus gracilis

Which part of the posterior column contains fibers from the lower limbs and trunk?

A. Lateral cuneate portion
B. Medial gracile portion
C. Ventral central portion
D. Contralateral dorsal portion

B. Medial gracile portion

A lesion damages the nucleus that receives posterior column input from the lower limbs. Which nucleus is affected?

A. Nucleus cuneatus
B. Nucleus ambiguus
C. Nucleus gracilis
D. Red nucleus

C. Nucleus gracilis

Fibers from the upper limb, upper trunk above T6, and neck ascend in the:

A. Medial gracile fasciculus
B. Lateral cuneate fasciculus
C. Ventral spinothalamic tract
D. Dorsal spinocerebellar tract

B. Lateral cuneate fasciculus

Posterior column fibers from the upper limb ultimately synapse on second-order neurons in the:

A. Nucleus gracilis
B. Nucleus solitarius
C. Nucleus cuneatus
D. Inferior olive

C. Nucleus cuneatus

A hemicord lesion damages the lateral portion of the posterior column at a cervical level. Which sensory region is most affected?

A. Lower limb
B. Upper limb and neck
C. Perianal saddle region
D. Contralateral face

B. Upper limb and neck

After first-order posterior column fibers synapse in the caudal medulla, the second-order neurons cross the midline as the:

A. External arcuate fibers
B. Spinothalamic commissure
C. Internal arcuate fibers
D. Posterior funicular fibers

C. Internal arcuate fibers

Once these second-order neurons decussate in the medulla, they ascend contralaterally as the:

A. Medial lemniscus
B. Lateral lemniscus
C. Spinocerebellar tract
D. Trigeminal tract

A. Medial lemniscus

A small lesion selectively damages the ventral portion of the medial lemniscus in the medulla. Which body region’s proprioceptive information is most likely affected?

A. Face
B. Upper limb
C. Neck
D. Foot and lower limb

D. Foot and lower limb

A small lesion selectively damages the dorsal portion of the medial lemniscus in the medulla. Which body region’s proprioceptive information is most likely affected?

A. Face
B. Upper limb
C. Neck
D. Foot and lower limb

B. Upper limb

A midbrain lesion damages the lateral portion of the medial lemniscus. Which sensory stream is most likely impaired?

A. Facial touch
B. Upper trunk vibration
C. Lower limb proprioception
D. Hand pain sensation

C. Lower limb proprioception

In the midbrain, fibers from the upper limb are located in which part of the medial lemniscus?

A. Medial portion
B. Ventral portion
C. Dorsal portion
D. Lateral portion

A. Medial portion

The medial-lateral arrangement of body fibers in the pons and midbrain is best described as:

A. Identical to spinal cord
B. Opposite the spinal cord
C. Identical to dorsal columns
D. Opposite the thalamus only

B. Opposite the spinal cord

Second-order neurons of the dorsal column-medial lemniscus pathway synapse on third-order neurons in which thalamic nucleus?

A. Ventral posterior medial
B. Lateral geniculate nucleus
C. Ventral posterior lateral
D. Ventral anterior nucleus

C. Ventral posterior lateral

After synapsing in the VPL, body sensory fibers reach cortex by passing through the:

A. Posterior limb, internal capsule
B. Anterior limb, internal capsule
C. External capsule only
D. Genu, internal capsule

A. Posterior limb, internal capsule

Thalamocortical somatosensory projections from the VPL terminate primarily in the:

A. Precentral gyrus
B. Superior temporal gyrus
C. Cingulate cortex
D. Postcentral gyrus

D. Postcentral gyrus

Most thalamocortical sensory fibers terminate in which cortical layer of primary somatosensory cortex?

A. Layer II
B. Layer IV
C. Layer V
D. Layer VI

D. Layer VI

Touch sensation from the face reaches the thalamus primarily through the trigeminal lemniscus and then synapses in the:

A. VPL nucleus
B. Pulvinar nucleus
C. Medial geniculate
D. VPM nucleus

D. VPM nucleus

A patient loses pain and temperature sensation after injury to the anterolateral pathway. Which tract is primarily involved?

A. Dorsal spinocerebellar tract
B. Medial longitudinal fasciculus
C. Spinothalamic tract
D. Fasciculus cuneatus

C. Spinothalamic tract

The primary afferents entering the spinothalamic pathway are best described as:

A. Large, heavily myelinated fibers
B. Small, often unmyelinated fibers
C. Fast motor efferent axons
D. Thick autonomic preganglionics

B. Small, often unmyelinated fibers

Which sensory modalities are primarily carried by the spinothalamic tract?

A. Fine touch, vibration, proprioception
B. Pain, temperature, gross touch
C. Smell, taste, visceral stretch
D. Position, stereognosis, graphesthesia

B. Pain, temperature, gross touch

First-order spinothalamic fibers enter the spinal cord through the:

A. Ventral root
B. Lateral corticospinal tract
C. Dorsal root
D. Posterior funiculus

C. Dorsal root

After entering the spinal cord, spinothalamic primary afferents first synapse mainly in which regions?

A. Lamina I and V
B. Lamina II only
C. Nucleus gracilis only
D. Clarke nucleus and VI

A. Lamina I and V

A painful stimulus applied to the foot travels in fibers that may ascend or descend a few spinal segments before synapsing. These fibers are traveling in:

A. Anterior white commissure
B. Lissauer tract
C. Medial lemniscus
D. Posterior column

B. Lissauer tract

Which statement best describes the crossing pattern of spinothalamic second-order neurons?

A. They cross in medulla
B. They remain ipsilateral throughout
C. They cross in anterior commissure
D. They cross in internal capsule

C. They cross in anterior commissure

A right lateral spinal cord lesion at T8 causes loss of left-sided pain and temperature beginning a few segments below the lesion. This occurs because spinothalamic fibers:

A. Cross immediately at entry
B. Cross after 2–3 segments
C. Ascend ipsilaterally to pons
D. Synapse first in thalamus

B. Cross after 2–3 segments

In the spinal cord, lower-limb pain and temperature fibers within the anterolateral white matter are located:

A. Most medially
B. Most dorsally
C. Most ventrally
D. Most laterally

D. Most laterally

In the spinothalamic tract, upper-limb fibers are located:

A. Most medially
B. Most laterally
C. Most ventrally
D. Most posteriorly

A. Most medially

Most ascending spinothalamic fibers carrying body sensation synapse in which thalamic nucleus?

A. VPM
B. VPL
C. Lateral geniculate
D. Ventral anterior

B. VPL

Some spinothalamic fibers terminate in the intralaminar nuclei of the thalamus, contributing especially to:

A. Fine touch discrimination
B. Emotional arousal of pain
C. Facial proprioception
D. Voluntary pain suppression

B. Emotional arousal of pain

Besides the intralaminar nuclei, some spinothalamic fibers also project to the:

A. Mediodorsal nucleus
B. Pulvinar only
C. Mammillary nucleus
D. Subthalamic nucleus

A. Mediodorsal nucleus

After thalamic processing, spinothalamic sensory information ultimately projects to the:

A. Precentral gyrus
B. Superior temporal gyrus
C. Postcentral gyrus
D. Cingulate gyrus

C. Postcentral gyrus

Besides the spinothalamic tract, which tract in the anterolateral column is most associated with the emotional and arousal aspects of pain?

A. Dorsal spinocerebellar tract
B. Spinoreticular tract
C. Fasciculus gracilis
D. Corticobulbar tract

B. Spinoreticular tract

Fibers in the spinoreticular tract terminate primarily in the:

A. Ventral posterior nucleus
B. Periaqueductal gray
C. Superior parietal lobule
D. Medullary-pontine reticular formation

D. Medullary-pontine reticular formation

The medullary-pontine reticular formation projects mainly to which thalamic nuclei in this pain pathway?

A. Geniculate nuclei
B. Intralaminar nuclei
C. Ventral anterior nuclei
D. Pulvinar nuclei

B. Intralaminar nuclei

Unlike the spinothalamic tract, the spinoreticular tract does not project to cortex in a:

A. Bilateral pattern
B. Somatotopic pattern
C. Descending pattern
D. Monosynaptic pattern

B. Somatotopic pattern

Diffuse cortical projections from the spinoreticular system are thought to promote:

A. Behavioral arousal
B. Fine discrimination
C. Motor inhibition
D. Visual tracking

A. Behavioral arousal

Which anterolateral tract projects to the periaqueductal gray matter and superior colliculus?

A. Spinocerebellar tract
B. Spinoreticular tract
C. Spinomesencephalic tract
D. Medial lemniscus

C. Spinomesencephalic tract

The spinomesencephalic tract is most directly involved in:

A. Position sense
B. Central pain modulation
C. Facial motor control
D. Stereognosis

B. Central pain modulation

In the notes, the spinomesencephalic tract is summarized as helping to:

A. Localize pain
B. Trigger arousal
C. Resolve pain
D. Intensify pain

C. Resolve pain

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Somatosensory information from primary cortex is conveyed next to the secondary somatosensory association cortex located in the:

A. Sylvian fissure region
B. Calcarine cortex
C. Cingulate gyrus
D. Internal capsule

A. Sylvian fissure region

The secondary somatosensory association cortex lies in the region called the:

A. Uncus
B. Precuneus
C. Parietal operculum
D. Insular pole

C. Parietal operculum

Further higher-order processing of somatosensory information occurs in the superior parietal lobule, which includes Brodmann areas:

A. 9 and 10
B. 5 and 7
C. 22 and 24
D. 41 and 42

B. 5 and 7

Cortical sensory loss is most likely caused by lesions of the:

A. Basal ganglia and association areas
B. Spinal roots and association areas
C. Somatosensory cortex and association areas
D. Cerebellar vermis and association areas

C. Somatosensory cortex and association areas

Gate control theory proposes that activation of which fibers can reduce pain at the dorsal horn?

A. A-delta fibers
B. C fibers
C. Sympathetic fibers
D. A-beta fibers

A. A-delta fibers

Rubbing or flicking an injured area may lessen pain because nonpain sensory input can:

A. Amplify spinothalamic firing
B. Reduce pain in dorsal horn
C. Block thalamic relay neurons
D. Silence primary motor cortex

B. Reduce pain in dorsal horn

The periaqueductal gray receives input from the hypothalamus, amygdala, and cortex in order to:

A. Initiate voluntary movement
B. Modulate pain
C. Produce REM sleep
D. Generate vestibular reflexes

B. Modulate pain

Descending pain inhibition from the periaqueductal gray reaches the dorsal horn through a relay in the:

A. Red nucleus
B. Ventral posterior nucleus
C. Rostral ventral medulla
D. Inferior olivary nucleus

C. Rostral ventral medulla

In this descending pain-modulating system, the rostral ventral medulla uses which neurotransmitter to influence the dorsal horn?

A. Serotonin
B. Dopamine
C. Acetylcholine
D. GABA

A. Serotonin

The notes also state that the rostral ventral medulla responds to substance P by projecting which transmitter into the dorsal horn?

A. Glycine
B. Histamine
C. Norepinephrine
D. Glutamate

C. Norepinephrine

An opioid analgesic reduces pain by acting on receptors distributed throughout which system?

A. Corticospinal motor pathway
B. Pain modulation pathway
C. Visual relay pathway
D. Vestibular pathway

B. Pain modulation pathway

Opiate receptors are present in many locations, but their highest concentrations are found on the:

A. Thalamus and cortex
B. Basal ganglia and cerebellum
C. Midbrain and medulla only
D. Peripheral nerves and dorsal horn

D. Peripheral nerves and dorsal horn

Which set contains only endogenous opiates?

A. Serotonin, dynorphin, glutamate
B. Endorphin, GABA, enkephalin
C. Enkephalin, endorphin, dynorphin
D. Dopamine, norepinephrine, endorphin

C. Enkephalin, endorphin, dynorphin

Enkephalins and dynorphins are specifically noted to be present in the dorsal horn and also in the:

A. RVM and periaqueductal gray
B. Thalamus and cortex
C. Hypothalamus and cerebellum
D. Basal ganglia and pons

A. RVM and periaqueductal gray

Which endogenous opioid is specifically associated with the hypothalamus rather than being listed directly in the dorsal horn?

A. Dynorphin
B. Enkephalin
C. Substance P
D. Endorphin

D. Endorphin

The hypothalamic location of endorphin is relevant because the hypothalamus is connected to the:

A. Ventral posterior nucleus
B. Periaqueductal gray matter
C. Internal capsule
D. Postcentral gyrus

B. Periaqueductal gray matter

The thalamus is part of which major brain division?

A. Mesencephalon
B. Telencephalon
C. Myelencephalon
D. Diencephalon

D. Diencephalon

Relative to the midbrain, the thalamus is located:

A. Rostral
B. Caudal
C. Dorsal only
D. Lateral only

A. Rostral

Which structure lies ventral to the thalamus?

A. Epithalamus
B. Hypothalamus
C. Midbrain
D. Cerebellum

B. Hypothalamus

Nearly all pathways that project to the cerebral cortex do so by first synapsing in the:

A. Thalamus
B. Midbrain
C. Medulla
D. Basal ganglia

A. Thalamus

In addition to sensory pathways, which motor-related systems relay information to the cerebrum through the thalamus?

A. Corticospinal and spinothalamic systems
B. Cerebellum and basal ganglia
C. Vestibular nuclei and retina
D. Amygdala and hippocampus

B. Cerebellum and basal ganglia

Which statement best describes thalamic nuclei?

A. All project diffusely only
B. All project to one cortex
C. None receive cortical feedback
D. Some are specific, some diffuse

D. Some are specific, some diffuse

Thalamic nuclei generally receive strong feedback from the:

A. Cortical areas they supply
B. Spinal cord dorsal horn
C. Peripheral sensory nerves
D. Contralateral cerebellum

A. Cortical areas they supply

Thalamic nuclei involved in motor and sensory projection are most often:

A. Bilateral and diffuse
B. Localized
C. Unmyelinated
D. Inhibitory only

B. Localized

The internal medullary lamina divides each thalamus by forming a:

A. Circular ring
B. Horizontal band
C. Y-shaped sheet
D. Vertical septum

C. Y-shaped sheet

The three main thalamic regions created by this lamina are the:

A. Medial, lateral, anterior groups
B. Dorsal, ventral, posterior groups
C. Rostral, caudal, midline groups
D. Pulvinar, geniculate, ventral groups

A. Medial, lateral, anterior groups

The medial geniculate nucleus primarily relays:

A. Pain information
B. Visual signals
C. Olfactory signals
D. Auditory input

D. Auditory input

Diffuse thalamic relays involved in cognition and limbic control, especially with frontal lobe relevance, are strongly associated with the:

A. Ventral posterior nucleus
B. Mediodorsal nucleus
C. Pulvinar nucleus
D. Ventral lateral nucleus

B. Mediodorsal nucleus

In addition to the mediodorsal nucleus, diffuse limbic and cognitive relays also involve the:

A. Geniculate nuclei and midline nuclei
B. Ventral posterior nuclei
C. Intralaminar and midline nuclei
D. Anterior and pulvinar nuclei

C. Intralaminar and midline nuclei

Nearly all sensory modalities except smell and hearing relay to primary cortical areas through the:

A. Anterior nuclear group
B. Medial nuclear group
C. Midline nuclei
D. Lateral nuclear group

D. Lateral nuclear group

Output from the cerebellum and basal ganglia heading toward primary motor cortex relays mainly in the:

A. Ventral lateral nucleus
B. Anterior nucleus
C. Pulvinar nucleus
D. Mediodorsal nucleus

A. Ventral lateral nucleus

The anterior nuclear group is best known for relaying:

A. Auditory signals
B. Motor planning signals
C. Limbic pathway input
D. Spinothalamic pain

C. Limbic pathway input

The pulvinar nucleus is located in the:

A. Posterior thalamus
B. Anterior thalamus
C. Medial thalamus
D. Ventral thalamus

A. Posterior thalamus

The pulvinar mainly relays visual and other sensory information broadly to:

A. Primary motor cortex
B. Brainstem nuclei
C. Spinal cord pathways
D. Association cortices

D. Association cortices

Thalamic nuclei located within the internal medullary lamina are called:

A. Midline nuclei
B. Intralaminar nuclei
C. Ventral nuclei
D. Geniculate nuclei

B. Intralaminar nuclei

The major input to the intralaminar nuclei comes especially from the:

A. Hippocampus
B. Cerebellum
C. Retina
D. Basal ganglia

D. Basal ganglia

Projections from the intralaminar nuclei to cortex are best described as:

A. Strictly somatotopic and widespread
B. Nonspecific and widespread
C. Purely motor and widespread
D. Purely visual and widespread

B. Nonspecific and widespread

The intralaminar nuclei are divided into two major subdivisions, the:

A. Caudal and rostral groups
B. Medial and lateral groups
C. Ventral and dorsal groups
D. Anterior and posterior groups

A. Caudal and rostral groups

Which caudal intralaminar nucleus is specifically described as very large?

A. Mediodorsal nucleus
B. Pulvinar nucleus
C. Ventral lateral nucleus
D. Centromedian nucleus

D. Centromedian nucleus

The rostral intralaminar nuclei help maintain alertness by relaying input from the:

A. Spinothalamic pathway
B. Olfactory cortex
C. Basal forebrain
D. Ascending reticular activating system

D. Ascending reticular activating system

The rostral intralaminar nuclei also have reciprocal connections with the:

A. Basal ganglia
B. Retina
C. Amygdala
D. Cerebellum

A. Basal ganglia

Nuclei located between the two thalami are called the:

A. Midline thalamic nuclei
B. Intralaminar nuclei
C. Pulvinar nuclei
D. Ventral nuclei

A. Midline thalamic nuclei

The thalamic reticular nucleus is best described anatomically as a:

A. Medial cluster within the thalamus
B. Thin sheet along lateral thalamus
C. Posterior pulvinar subdivision
D. Midline bridge between thalami

B. Thin sheet along lateral thalamus

Which statement uniquely distinguishes the thalamic reticular nucleus from other thalamic nuclei?

A. It relays auditory input
B. It projects diffusely to cortex
C. It does not project to cortex
D. It receives only brainstem input

C. It does not project to cortex

The thalamic reticular nucleus primarily receives input from other thalamic nuclei and sends output:

A. Back to the thalamus
B. To spinal cord interneurons
C. Directly to motor cortex
D. Into basal ganglia loops

A. Back to the thalamus

The neuronal population of the thalamic reticular nucleus is composed predominantly of:

A. Cholinergic excitatory neurons
B. Glutamatergic relay neurons
C. Dopaminergic projection neurons
D. Inhibitory GABAergic neurons

D. Inhibitory GABAergic neurons

A lesion that disrupts the thalamic reticular nucleus would most directly impair which function?

A. Regulation of thalamic activity
B. Olfactory discrimination
C. Cerebellar output to cortex
D. Peripheral pain transduction

A. Regulation of thalamic activity

In addition to input from thalamic nuclei, the thalamic reticular nucleus also receives input from the cortex, reticular formation, and:

A. Hippocampus
B. Forebrain
C. Cerebellum
D. Amygdala

B. Forebrain

Input from the brainstem reticular formation to the thalamic reticular nucleus helps support its role in modulating:

A. Fine touch localization
B. Voluntary motor planning
C. Level of consciousness
D. Visual acuity testing

C. Level of consciousness

Which circuit description best matches the thalamic reticular nucleus?

A. Excitatory thalamus-to-cortex relay
B. Inhibitory thalamus-to-thalamus regulator
C. Motor cortex-to-spinal tract
D. Limbic cortex-to-hypothalamus relay

B. Inhibitory thalamus-to-thalamus regulator

_____ Nuclei= relays inputs from many pathways to the cortex in reciporical fashion. includes medial, lateral, and anteiror nuclear groups

Relay

_____ Nuclei= within the internal medullary lamina of the thalamus and is involved with relay of inputs from the basal ganglia to widespread cortical locations and is involved in relay of ARAS which promotes alertness

Intralaminar

_____ Nucleus= located in sheet lateral to thalamus within its capsule and has a mainly inihibitory role within the thalamus relaying thalamic inputs back to the thalamus and
modulating other inputs. Also plays role in modulating attention/alertness

Reticular

A patient with a lesion in a major somatosensory pathway reports abnormal tingling despite objective sensory loss. This symptom is best described as:

A. Dysarthria
B. Paresthesia
C. Hyperreflexia
D. Ataxia

B. Paresthesia

A patient with a posterior column lesion reports numbness, tingling, and a tight band-like sensation around the limb. Which lesion location best matches this symptom pattern?

A. Posterior column
B. Thalamus
C. Anterolateral column
D. Peripheral motor nerve

A. Posterior column

A lesion of the anterolateral column is most likely to produce which abnormal sensory complaint?

A. Tight band-like numbness
B. Loss of graphesthesia only
C. Sharp, burning pain
D. Isolated proprioceptive loss

C. Sharp, burning pain

A patient develops severe contralateral pain after a thalamic stroke. This syndrome is called:

A. Brown-Séquard syndrome
B. Lhermitte syndrome
C. Wallenberg syndrome
D. Dejerine-Roussy syndrome

D. Dejerine-Roussy syndrome

Flexing the neck causes an electric shock-like sensation running down the back and into both arms. This finding is called:

A. Romberg sign
B. Hoffman's sign
C. Lhermitte sign
D. Babinski sign

C. Lhermitte sign

A patient has pain and numbness radiating down the lateral leg in a dermatomal pattern, and the pain worsens when the nerve root is stretched. This is most consistent with:

A. Mononeuropathy
B. Radiculopathy
C. Polyneuropathy
D. Myelopathy

B. Radiculopathy

Which statement best describes symptoms from a peripheral nerve lesion compared with radiculopathy?

A. They never cause numbness
B. They affect the opposite limb
C. They produce symptoms in the nerve’s region
D. They always involve the spinal cord

C. They produce symptoms in the nerve’s region

An unpleasant, abnormal sensory experience that is not simply decreased sensation is termed:

A. Dysesthesia
B. Hypesthesia
C. Paresthesia
D. Anesthesia

A. Dysesthesia

Pain produced by a stimulus that is normally not painful is called:

A. Hyperpathia
B. Allodynia
C. Hypesthesia
D. Radiculopathy

B. Allodynia

A pinprick that is mildly painful in most people causes an exaggerated painful response in a patient with central sensitization. This is best termed:

A. Hyperpathia or hyperalgesia
B. Dysesthesia or paresthesia
C. Anesthesia dolorosa
D. Allodynia only

A. Hyperpathia or hyperalgesia

Decreased sensation on neurologic examination is termed:

A. Hypalgesia
B. Hypesthesia
C. Hyperesthesia
D. Dysesthesia

B. Hypesthesia

The most common cause of spinal cord dysfunction is:

A. Intrinsic demyelination
B. Vascular malformation
C. Extrinsic compression
D. Congenital syrinx

C. Extrinsic compression

A patient with spinal cord dysfunction is expected to develop both motor and sensory deficits beginning:

A. At unrelated random levels
B. At the same general level
C. Only below the sacral cord
D. Only on one side initially

B. At the same general level

Why might the clinical level of motor and sensory deficits not exactly match the anatomical level of spinal cord dysfunction?

A. Reflexes bypass the cord
B. The cortex compensates immediately
C. Peripheral nerves cross twice
D. Ascending and descending fibers shift levels

D. Ascending and descending fibers shift levels

Immediately after a traumatic spinal cord injury, a patient has flaccid paralysis, absent deep tendon reflexes, hypotension, and loss of sphincter tone. This phase is called:

A. Neuroleptic rigidity
B. Spinal shock
C. Cauda equina syndrome
D. Autonomic dysreflexia

B. Spinal shock

As spinal shock resolves over time, which pattern is most likely to emerge?

A. Hyperreflexia and spasticity
B. Fasciculations and atrophy
C. Flaccidity with areflexia
D. Progressive sensory extinction

A. Hyperreflexia and spasticity

An older patient with long-standing cervical spondylosis develops progressive spinal cord dysfunction over months. This presentation is most consistent with:

A. Acute myelitis
B. Chronic myelopathy
C. Anterior cord infarct
D. Spinal shock

B. Chronic myelopathy

A patient lost the ability to walk from tumor-related cord compression before treatment. According to the material, what is the approximate chance of ever regaining walking?

A. 20% regain walking
B. 50% regain walking
C. 80% regain walking
D. Nearly all regain walking

A. 20% regain walking

Degenerative disorders of the spine can produce both upper and lower motor neuron signs because they may compress both the:

A. Cerebellum and brainstem
B. Cord and thalamus
C. Cortex and cerebellum
D. Nerve roots and cord

D. Nerve roots and cord

A patient has metastatic spinal cord compression but is still walking. What is the most important management principle from the notes?

A. Decompress immediately
B. Wait for biopsy first
C. Start rehab only
D. Observe for progression

A. Decompress immediately

When a compressive spinal tumor is detected and removed before the patient loses ambulation, the expected outcome is best summarized as:

A. Most still lose walking
B. Most keep walking ability
C. Recovery is unpredictable
D. Paralysis becomes permanent

B. Most keep walking ability

The most common site of metastatic tumor causing spinal cord compression is the:

A. Epidural space
B. Subarachnoid space
C. Central canal
D. Intramedullary cord

A. Epidural space

Spinal cord infarction most commonly results from occlusion of which vessel?

A. Posterior spinal artery
B. Radicular artery only
C. Vertebral artery
D. Anterior spinal artery

D. Anterior spinal artery

Occlusion of the anterior spinal artery most classically produces:

A. Brown-Séquard syndrome
B. Central cord syndrome
C. Anterior cord syndrome
D. Posterior cord syndrome

C. Anterior cord syndrome

Watershed infarcts are infarcts occurring in tissue located:

A. Between arterial territories
B. Within venous sinuses
C. Inside the central canal
D. Beneath the pia only

A. Between arterial territories

Which region is specifically identified as a vulnerable watershed zone in the spinal cord?

A. Cervicomedullary junction
B. Sacral enlargement
C. Mid-thoracic cord
D. Conus medullaris

C. Mid-thoracic cord

A vascular defect that can be difficult to diagnose yet may cause transient episodes of spinal cord dysfunction is:

A. Cavernous malformation
B. Berry aneurysm
C. Epidural hematoma
D. Spinal dural AVM

D. Spinal dural AVM

Myelitis is best defined as:

A. Inflammation of spinal cord
B. Degeneration of dorsal roots
C. Compression of cauda equina
D. Ischemia of anterior horn

A. Inflammation of spinal cord

A patient develops rapidly progressive spinal cord dysfunction with fever, elevated WBC count, and bright T2 signal abnormalities on spinal MRI. Which cause is specifically listed in the material?

A. Epidural lipomatosis
B. Dural tear
C. Epidural abscess
D. Chronic spondylosis

C. Epidural abscess

If myelitis is not treated immediately, the major feared consequence is:

A. Only transient numbness
B. Irreversible spinal damage
C. Isolated facial weakness
D. Benign spontaneous recovery

B. Irreversible spinal damage

A 61-year-old man cannot identify a key placed in his left hand with eyes closed, but pinprick, vibration, and crude touch are largely preserved. The lesion is most likely in the:

A. Right primary somatosensory cortex
B. Left primary somatosensory cortex
C. Left lateral pons
D. Left VPL nucleus

A. Right primary somatosensory cortex

A patient with a right parietal cortical lesion is most likely to have which sensory deficit pattern?

A. Ipsilateral pain and temperature loss
B. Contralateral sensory deficit predominance
C. Bilateral glove-stocking numbness
D. Contralateral facial pain only

B. Contralateral sensory deficit predominance

Which sensory modalities are often most affected by a lesion of the primary somatosensory cortex?

A. Pain and temperature
B. Crude touch and pain
C. Discriminatory touch and proprioception
D. Olfaction and vibration

C. Discriminatory touch and proprioception

A patient has intact primary sensation but cannot recognize numbers traced on the palm and ignores simultaneous stimulation on the affected side. This pattern is most consistent with:

A. Cortical sensory loss
B. Spinothalamic tract syndrome
C. Peripheral neuropathy
D. Transverse cord lesion

A. Cortical sensory loss

A small infarct of the left VPL nucleus would most likely cause:

A. Ipsilateral body sensory loss
B. Contralateral body sensory loss
C. Bilateral vibration loss
D. Contralateral facial weakness only

B. Contralateral body sensory loss

A thalamic lesion extends beyond the VPL/VPM into adjacent structures. Which additional finding may occur?

A. Aphasia or neglect
B. Ptosis or miosis
C. Hemiplegia or hemianopia
D. Ataxia or tremor

C. Hemiplegia or hemianopia

A lesion of the thalamic somatosensory radiation is most likely to produce sensory loss plus:

A. Hemiparesis from corticospinal involvement
B. Ipsilateral facial paralysis
C. Bilateral lower motor weakness
D. Contralateral cerebellar signs

A. Hemiparesis from corticospinal involvement

Sensory deficits from lesions of the VPL/VPM nuclei are most often noticed by patients in the:

A. Trunk and proximal legs
B. Hands and face
C. Neck and shoulders
D. Feet and occiput

B. Hands and face

A dorsolateral brainstem infarct causes loss of pain and temperature on the left face and right body. The lesion is most likely in the:

A. Right medial medulla
B. Left medial pons
C. Left lateral pons or medulla
D. Right primary sensory cortex

C. Left lateral pons or medulla

The crossed sensory findings in a lateral pontine or lateral medullary lesion are due to involvement of the:

A. Medial lemniscus and VPL
B. Trigeminal nucleus and spinothalamic tract
C. Posterior columns and corticospinal tract
D. VPM and internal capsule

B. Trigeminal nucleus and spinothalamic tract

A lesion of the medial medulla involving the medial lemniscus would most likely cause:

A. Contralateral vibration and proprioception loss
B. Ipsilateral facial pain loss
C. Contralateral pain and temperature loss
D. Bilateral distal numbness

A. Contralateral vibration and proprioception loss

A diabetic patient reports gradually progressive numbness in both feet that later involves the hands, in a symmetric distal pattern. This is most characteristic of:

A. Brown-Sequard syndrome
B. Medial medullary syndrome
C. Thalamic radiation lesion
D. Distal symmetrical polyneuropathy

D. Distal symmetrical polyneuropathy

“Glove and stocking” sensory loss most strongly localizes to the:

A. Primary sensory cortex
B. Nerve roots or peripheral nerves
C. Lateral medulla
D. Posterior thalamus

B. Nerve roots or peripheral nerves

A complete transverse lesion of the thoracic spinal cord would interrupt:

A. Only sensory pathways below lesion
B. Only motor pathways below lesion
C. All sensory and motor pathways below lesion
D. Ipsilateral dorsal column modalities only

C. All sensory and motor pathways below lesion

Which of the following is a recognized cause of a transverse cord lesion?

A. Migraine aura
B. Myasthenia gravis
C. Transverse myelitis
D. Myotonic dystrophy

C. Transverse myelitis

A knife wound causes hemisection of the right spinal cord at T10. Which deficit is expected below the lesion?

A. Right pain loss only
B. Left proprioception loss only
C. Left upper motor weakness
D. Right vibration loss

D. Right vibration loss

In Brown-Sequard syndrome, ipsilateral upper motor neuron weakness results from damage to the:

A. Lateral corticospinal tract
B. Anterior horn cells
C. Spinocerebellar tract
D. Medial longitudinal fasciculus

A. Lateral corticospinal tract

In Brown-Sequard syndrome, contralateral pain loss is caused by damage to the:

A. Posterior column
B. Medial lemniscus
C. Anterolateral column
D. Ventral corticospinal tract

C. Anterolateral column

A patient with spinal cord hemisection has ipsilateral loss of vibration, light touch, and proprioception below the lesion. The damaged structure is the:

A. Anterolateral system
B. Posterior column
C. Spinoreticular pathway
D. Ventral horn

B. Posterior column

Which of the following is a recognized cause of Brown-Sequard syndrome?

A. Penetrating injury
B. Basilar migraine
C. Temporal arteritis
D. Hydrocephalus

A. Penetrating injury

A 29-year-old man develops a spinal cord injury in the cervical region. He loses pain and temperature sensation over both shoulders and arms in a “cape-like” pattern, but other sensory findings are initially limited. Which spinal cord syndrome best explains this pattern?

A. Anterior cord syndrome
B. Posterior cord syndrome
C. Central cord syndrome
D. Brown-Sequard syndrome

C. Central cord syndrome

A patient has a small lesion in the center of the spinal cord that damages the crossing spinothalamic fibers. What sensory loss is expected first?

A. Bilateral suspended pain loss
B. Ipsilateral vibration loss
C. Contralateral facial numbness
D. Stocking-glove numbness

A. Bilateral suspended pain loss

A patient with an enlarging central cord lesion develops hand weakness at the level of the lesion and spastic weakness in the legs below the lesion. Which structures are now likely involved?

A. Posterior column only
B. Anterior horn and corticospinal tract
C. Medial lemniscus and thalamus
D. Cerebellum and vestibular nuclei

B. Anterior horn and corticospinal tract

A severe central cord lesion causes major loss of pain and temperature below the lesion, but sensation in the sacral area is relatively preserved. This “sacral sparing” is best explained by:

A. Lateral sacral fiber location
B. Posterior column preservation
C. Brainstem compensation
D. Bilateral thalamic input

A. Lateral sacral fiber location

Which of the following is a common cause of central cord syndrome?

A. B12 deficiency
B. Anterior spinal infarct
C. Spinal contusion
D. Tabes dorsalis

C. Spinal contusion

A 55-year-old man has loss of vibration sense and proprioception below a spinal cord lesion. Pain and temperature are preserved. Which syndrome is most likely?

A. Posterior cord syndrome
B. Central cord syndrome
C. Anterior cord syndrome
D. Cauda equina syndrome

A. Posterior cord syndrome

A patient with untreated vitamin deficiency develops progressive loss of vibration and joint position sense. A large lesion later produces upper motor neuron signs. Which syndrome best matches this presentation?

A. Central cord syndrome
B. Posterior cord syndrome
C. Anterior cord syndrome
D. Syringobulbia syndrome

B. Posterior cord syndrome

A patient cannot feel pain or temperature below a spinal cord lesion, but vibration and proprioception remain intact. He also develops bowel and bladder incontinence. Which syndrome is most likely?

A. Posterior cord syndrome
B. Central cord syndrome
C. Anterior cord syndrome
D. Lateral medullary syndrome

C. Anterior cord syndrome

Which cause is classically associated with anterior cord syndrome?

A. Tertiary syphilis
B. B12 deficiency
C. Anterior spinal artery infarct
D. Diabetic neuropathy

C. Anterior spinal artery infarct

A patient develops sudden anterior cord syndrome after a vascular event involving the spinal cord. Which artery was most likely affected?

A. Anterior spinal artery
B. Posterior cerebral artery
C. Middle cerebral artery
D. Basilar artery

A. Anterior spinal artery

Sensory information from the rectum, bladder, and genitals enters the spinal cord through which roots?

A. T11-L1
B. L1-L2
C. S2-S4
D. S4-Co1

C. S2-S4

Sensory signals from the rectum, bladder, and genitals reach higher centers through:

A. Dorsal columns only
B. Spinothalamic tract
C. Cerebellar pathways
D. Both somatosensory pathways

D. Both somatosensory pathways

Voluntary somatic motor fibers that control the pelvic floor arise primarily from:

A. Anterior horn at S2-S4
B. Intermediolateral column at T1-T4
C. Dorsal horn at S2-S4
D. Onuf nucleus at T11-L2

A. Anterior horn at S2-S4

The sphincteromotor nucleus of Onuf primarily controls the:

A. Detrusor and trigone
B. Urethral and anal sphincters
C. Internal and bladder neck
D. Pelvic splanchnic ganglia

B. Urethral and anal sphincters

Parasympathetic outflow to the pelvis arises from the:

A. Intermediolateral column T11-L2
B. Pontine micturition center
C. Frontal micturition cortex
D. Sacral nuclei at S2-S4

D. Sacral nuclei at S2-S4

Sympathetic outflow to the pelvis arises mainly from the:

A. Intermediolateral column T11-S2
B. Sacral nuclei at S2-S4
C. Anterior horn at S2-S4
D. Posterior horn at T11-S2

A. Intermediolateral column T11-S2

For a central nervous system lesion to reliably impair bowel, bladder, or sexual function, it usually must be:

A. Unilateral and cortical
B. Limited to one root
C. Bilateral
D. Restricted to dorsal columns

C. Bilateral

Normal bladder emptying is best described as being under:

A. Reflex control only
B. Voluntary control
C. Sympathetic control only
D. Sacral control only

B. Voluntary control

During normal filling, conscious awareness of bladder fullness depends on sensation reaching the:

A. Sensory cortex
B. Cerebellar cortex
C. Pontine tegmentum
D. Basal ganglia

A. Sensory cortex

The conscious initiation of voiding begins with activation of the:

A. Lateral hypothalamus
B. Sacral parasympathetic nuclei
C. Primary motor cortex
D. Medial frontal micturition centers

D. Medial frontal micturition centers

Which structure is the main regulator coordinating the voiding program once micturition is initiated?

A. Onuf nucleus
B. Anterior horn
C. Pontine micturition center
D. Dorsal root ganglion

C. Pontine micturition center

Voluntary relaxation of the external sphincter during urination first helps by:

A. Activating sympathetics
B. Inhibiting internal sphincter sympathetics
C. Silencing sacral afferents
D. Contracting pelvic floor muscles

B. Inhibiting internal sphincter sympathetics

During normal voiding, parasympathetic activation causes the:

A. Detrusor to contract
B. Internal sphincter to contract
C. Pelvic floor to contract
D. Urethra to shorten

A. Detrusor to contract

Once urination begins, continued sensation of urine flow mainly:

A. Inhibits detrusor contraction
B. Activates Onuf nucleus
C. Closes the internal sphincter
D. Maintains the voiding reflex

D. Maintains the voiding reflex

When urine flow stops, bladder emptying normally ends because the:

A. Pontine center is destroyed
B. Detrusor relaxes via urethral reflex
C. Parasympathetics permanently stop
D. External sphincter paralyzes

B. Detrusor relaxes via urethral reflex

A patient with bilateral frontal lobe damage urinates automatically when the bladder fills and is unaware of fullness. The damaged area most likely is the:

A. Sacral parasympathetic nuclei
B. Pontine micturition center
C. Medial frontal micturition centers
D. Sphincteromotor nucleus of Onuf

C. Medial frontal micturition centers

Bilateral lesions of the medial frontal micturition centers typically cause:

A. Overflow retention only
B. Loss of detrusor muscle
C. Anal sphincter spasm
D. Reflex incontinence without awareness

D. Reflex incontinence without awareness

Which condition is a recognized cause of bilateral medial frontal micturition center damage?

A. Hydrocephalus
B. Pernicious anemia
C. Tabes dorsalis
D. Anterior spinal infarct

A. Hydrocephalus

A spinal cord lesion below the pontine micturition center but above the conus medullaris first produces which bladder state?

A. Spastic bladder
B. Neurogenic sphincter spasm
C. Atonic bladder
D. Normal reflex bladder

C. Atonic bladder

Weeks after a spinal cord lesion below the pontine micturition center and above the conus medullaris, the bladder most often becomes:

A. Permanently areflexic
B. Hyperreflexive and spastic
C. Fully normal
D. Sensory only impaired

B. Hyperreflexive and spastic

A patient with an early flaccid neurogenic bladder has marked urinary retention. Which additional finding is most expected in the more severe form?

A. Sacral anesthesia only
B. Complete spontaneous drainage
C. Bladder distention
D. Fecal urgency alone

C. Bladder distention

In a less severe atonic bladder, the patient voids incompletely. Which measurement would be increased?

A. Bladder compliance
B. Post-void residual volume
C. Anal resting pressure
D. Detrusor reflex latency

B. Post-void residual volume

A patient with a spastic neurogenic bladder feels sudden urgency even when the bladder contains only a small amount of urine. What is the main problem?

A. Detrusor-sphincter dyssynergia
B. Pudendal nerve transection
C. Loss of cortical sensation
D. Complete sphincter paralysis

A. Detrusor-sphincter dyssynergia

In a hyperreflexive bladder, the abnormal urgency is mainly caused by:

A. Internal sphincter fibrosis
B. Detrusor spasms at low volume
C. Bladder outlet obstruction
D. Loss of urethral sensation

B. Detrusor spasms at low volume

A hyperreflexive bladder is also called a:

A. Atonic bladder
B. Flaccid bladder
C. Spastic bladder
D. Overflow bladder

C. Spastic bladder

Which of the following can cause either an atonic bladder or a hyperreflexive bladder?

A. Cataracts
B. Spinal tumors
C. Otitis media
D. Myasthenia gravis

B. Spinal tumors

Multiple sclerosis can cause which bladder problem?

A. Only stress incontinence
B. Only normal voiding
C. Only overflow retention
D. Atonic or hyperreflexive bladder

D. Atonic or hyperreflexive bladder

Trauma involving the nervous system can lead to:

A. Only spastic bladder
B. Only flaccid bowel
C. Atonic or spastic bladder
D. Only sensory urgency

C. Atonic or spastic bladder

Peripheral neuropathies usually cause which bladder pattern?

A. Flaccid more than spastic
B. Spastic more than flaccid
C. Normal detrusor function
D. Isolated sphincter hypertonia

A. Flaccid more than spastic

In peripheral neuropathy, flaccid bladder commonly occurs because of loss of:

A. Sympathetic flow to trigone
B. Parasympathetic flow to detrusor
C. Cortical input to pons
D. Sensory flow to cerebellum

B. Parasympathetic flow to detrusor

A patient with diabetic neuropathy develops urinary dribbling from an overfilled bladder. Which diagnosis best fits?

A. Stress incontinence
B. Reflex incontinence
C. Overflow incontinence
D. Urge suppression

C. Overflow incontinence

Which condition is classically associated with flaccid neurogenic bladder from peripheral nerve involvement?

A. Hydrocephalus
B. Diabetic neuropathy
C. Frontal meningioma
D. Pontine stroke

B. Diabetic neuropathy

Which lower spinal condition can cause a flaccid bladder?

A. Temporal lobe seizure
B. Basal ganglia infarct
C. Cauda equina syndrome
D. Cerebellar hemorrhage

C. Cauda equina syndrome

A large lumbar disc herniation most commonly causes which bladder pattern if sacral pathways are affected?

A. Spastic bladder
B. Flaccid bladder
C. Normal bladder
D. Painful bladder only

B. Flaccid bladder

The term “neurogenic bladder” refers to:

A. Only flaccid bladder states
B. Only spastic bladder states
C. Bladder pain from infection
D. Flaccid or spastic bladder

D. Flaccid or spastic bladder

Control of bowel function, like micturition, begins in motor pathways from the:

A. Medial frontal lobes
B. Occipital cortex
C. Basal ganglia only
D. Cerebellar vermis

A. Medial frontal lobes

The internal anal sphincter is mainly controlled by:

A. Pudendal somatic fibers
B. Sacral parasympathetics
C. Thoracic sympathetics only
D. Vagal motor fibers

B. Sacral parasympathetics

The external anal sphincter is mainly controlled by:

A. Sacral parasympathetics
B. Pelvic nerves from Onuf
C. Vagus to pelvic floor
D. Lumbar sympathetic chain

B. Pelvic nerves from Onuf

Pelvic floor muscles are innervated mainly by:

A. Sacral anterior horn neurons
B. Thoracic lateral horn neurons
C. Dorsal root ganglia
D. Pontine autonomic nuclei

A. Sacral anterior horn neurons

Damage to descending motor pathways to the anal sphincters tends to make the sphincters:

A. Spastic and continent
B. Flaccid and incontinent
C. Hypertrophied and painful
D. Rigid and retained

B. Flaccid and incontinent

Why can neurological bowel lesions produce constipation as well as incontinence?

A. Loss of vagal tone
B. Loss of pancreatic enzymes
C. Loss of parasympathetics to descending colon
D. Loss of sympathetic supply only

C. Loss of parasympathetics to descending colon

Parasympathetic stimulation of GI motility proximal to the descending colon is supplied mainly by:

A. CN III
B. CN VII
C. CN IX
D. CN X

D. CN X

Bowel dysfunction of neurological origin can result from damage to which locations?

A. Only frontal cortex
B. Only sacral roots
C. Only thoracic cord
D. Brain, cord, or sacral roots

D. Brain, cord, or sacral roots

Sensation from the genitals is carried mainly by the:

A. Obturator nerve
B. Pudendal nerve
C. Femoral nerve
D. Genitofemoral nerve

B. Pudendal nerve

Genital sensory fibers enter the spinal cord primarily at:

A. L1-L2
B. T11-L1
C. S2-S4
D. S4-Co1

C. S2-S4

Genital sensation helps mediate a reflex involving:

A. Only somatic pathways
B. Only sensory cortex
C. Only corticospinal fibers
D. Only autonomic pathways

D. Only autonomic pathways

In females, parasympathetic stimulation causes Bartholin glands to:

A. Stop secreting mucus
B. Secrete mucus
C. Contract skeletal muscle
D. Produce estrogen

B. Secrete mucus

In females, vaginal secretions are stimulated mainly by:

A. Sympathetics
B. Parasympathetics
C. Pudendal motor fibers
D. Somatic reflex arcs

A. Sympathetics

In both sexes, erection is primarily mediated by:

A. Sympathetics
B. Parasympathetics
C. Corticospinal fibers
D. Dorsal column pathways

B. Parasympathetics

In males, ejaculation is primarily mediated by a:

A. Parasympathetic skin reflex
B. Sympathetic reflex
C. Pudendal sensory reflex
D. Cerebellar reflex

B. Sympathetic reflex

During male ejaculation, which muscle type contracts along the reproductive tract?

A. Cardiac muscle
B. Skeletal muscle only
C. Smooth muscle
D. Extraocular muscle

C. Smooth muscle

A spinal cord lesion may affect erection and ejaculation, but the severity is often:

A. Fixed and predictable
B. Always complete
C. Variable
D. Limited to ejaculation

C. Variable

Which of the following can also contribute to sexual dysfunction besides spinal cord disease?

A. Peripheral nerve disease
B. Corneal abrasion
C. Otosclerosis
D. Nephrolithiasis

A. Peripheral nerve disease

Syringomyelia is best defined as a:

A. Brainstem aneurysm
B. Fluid-filled spinal cavity
C. Tumor of dorsal roots
D. Peripheral nerve cyst

B. Fluid-filled spinal cavity

Which of the following is a recognized cause of syringomyelia?

A. Congenital abnormalities
B. Hyperthyroidism
C. Meningococcal rash
D. Temporal arteritis

A. Congenital abnormalities

Posttraumatic syringomyelia is best described as:

A. Immediate spinal hemorrhage
B. Delayed sequela of SCI
C. Congenital sacral cyst
D. Acute viral myelitis

B. Delayed sequela of SCI