Neuroanatomy/Syndromes Flashcards
1
Q
Dermatomes:
T4
T10
S3-Coccygeal
A
T4 = Nipples
T10 = Umbilicus
S3-Coccygeal = Perineum
2
Q
Mononeuropathy vs. Polyneuropathy
vs. Radiculopathy
A
Mononeuropathy = dysfunction of single nerve
Polyneuropathy = diffuse dysfunction of nerves
Radiculopathy = dysfunction of spinal nerves or their roots
3
Q
- Symetrical bilateral proximal limb weakness
- Waddling Gait
- Atrophy and hyporeflexia
- No involvement of face or orbits
A
MYOPATHY
note proximal weakness
Waddling gate = pelvis drops on striding leg due to inability of contralateral hip muscles to keep hips level
4
Q
- Ptosis
- Ophthalmopareis (eye movement abnormal)
- Dysarthria (enunciation)
- Dysphagia (swallowing)
- Dysphonia (abnormal voice)
A
NEUROMUSCULAR JUNCTIONOPATHY
Fine movement of eyes first to go - IN ALL DIRECTIONS –> not just one cranial nerve
5
Q
- Symmetric bilateral somatosensory loss
- Just toes
- Up to knees + hands
- Hyporeflexia
- Gait abnormalities
- Ataxic Gait (wide stance)
- Slapping Gait
- Steppage Gait
- Injuries to feet and lower legs
- Orthostatic hypotension
A
POLYNEUROPATHY
(Diffuse peripheral neuropathy)
Note ataxic and slapping gait due to loss of proprioception
6
Q
- Somatosensory loss of all modalities of part of hand
- Anterior skin and distal posterior skin of thumb, index/middle finger and lateral half of ring finger
- Thenar weakness and atrophy
- Weak thumb opposition > flexion and abduction
A
MEDIAN NEUROPATHY AT THE CARPAL TUNNEL
Note sensory loss of all modalities - this must be a peripheral nerve and not something in the spinal cord
7
Q
- Somatosensory loss of all modalities
- Skin of anterior and posterior parts of pinky and half of ring finger
- Lower motor abnormalities of all hand muscles EXCEPT THENAR MUSCLES
A
ULNAR NEUROPATHY AT THE ELBOW
Think “funny bone”
8
Q
- Somatosensory loss of all modalities
- Skin on lateral part of posterior hand (proximal thumb, index, middle and lateral half of ring fingers)
- Wristdrop
- Grip weakness when no fully extended
A
RADIAL NEUROPATHY AT THE SPIRAL GROOVE
9
Q
- Unilateral somatosensory loss of proximal portion of lateral leg
A
LATERAL FEMORAL CUTANEOUS NEUROPATHY AT THE INGUINAL LIGAMENT
10
Q
- Unilateral somatosensory loss of skin on:
- Lateral part of distal leg
- Superior and medial parts of foot
- Lower motor neuron abnormalites causing
- Foot dorsiflexion weakness
- Foot Eversion weakness
- Toe Extension weakenss
A
COMMON PERONEAL NEUROPATHY AT THE KNEE
Note that foot inversion is maintained!
11
Q
- Somatosensory loss of skin on:
- Distal, lateral portion of the leg
- Superior and medial portions of foot
- Lower motor neuron abnormalities causing:
- Foot dorsiflexion weakness
- Foot eversion weakness
- Foot inversion weakness
- Toe extension weakness
A
FIFTH LUMBAR RADICULOPATHY
Radiculopathy = problem with spinal nerve
Note FOOT INVERSION WEAKNESS - only way to distinguish from common peroneal
Less commonly involves upper leg:
Lateral proximal sensory loss, hip abduction and knee flexion weakness
12
Q
- Somatosensory loss involving skin of:
- Posterior portions of proximal and distal legs
- Inferior and lateral portion of foot
- LMN abnormalities causing weakness of:
- Hip extension
- Foot plantarflexion
- Toe Flexion
- Hyporeflexia of achilles
A
FIRST SACRAL RADICULOPATHY
All on back side of leg
13
Q
- Somatosensory loss of skin on:
- Posterior parts of proximal and distal arm and hand
- LMN signs causing weakness of:
- Elbow extension
- Finger extension
- Hand pronation
- Triceps Hyporeflexia
A
SEVENTH CERVICAL RADICULOPATHY
All back of arm
14
Q
- Somatosensory loss of skin on:
- Lateral portions distal and proximal arm
- anterior and posterior thumb and index finger
- LMN signs causing weakness of
- Elbow flexion
- Hand Supination
- Biceps and brachioradialis hyporeflexia
A
SIXTH CERVICAL RADICULOPATHY
All lateral/front of arm - think of dermatome man and which comes first, 6 or 7 (6 on lateral side)
15
Q
Cross-section of Spinal Cord and name of pathology?
- Anteriolateral Column
- Posterior Column
- Lateral Column
- Anterior/Posterior Horns
A
Spinal cord dysfunction = MYELOPATHY
- Anteriolateral Column = “Spinothalamic Tract” (Pain, temp and gross touch)
- Posterior Column = CONSCIOUS proprioception, fine touch and vibration
- Lateral Column = “Corticospinal Tract” (upper motor neurons)
16
Q
- Somatosensory loss of perineum
- Loss of control of urination, defecation or genital function
- No motor neuron abnormalities
A
LOWER SACRAL MYELOPATHY / CAUDA EQUINA SYNDROME
17
Q
- LMN signs of:
- Foot dorsiflexion, foot inversion, foot eversion
- UMN signs of:
- Foot plantarflexion
- Etc.
A
LUMBOSACRAL ENLARGEMENT MYELOPATHY
Use knowledge of spinal nerve radiculopathies to determine level of lesion (LMN signs at, UMN signs below)
18
Q
- Somatosensory loss in ring around chest
- Loss of control of urination, defecation, genital function
- Paraparesis (weakness of both legs)
- Hyperreflexia
- Weakness worse distally
- Dorsiflexion worse than plantarflexion
- SPASTIC gait (SWINGING of legs around)
A
THORACIC MYELOPATHY
Spastic gait instead of steppage gait because can’t even flex knees
19
Q
- Somatosensory and motor losses of arms, trunk and legs
A
CERVICAL ENLARGEMENT MYELOPATHY
Use radiculopathy knowledge of arms to determine level
C6 = lateral/front arm LMN sign + back arm UMN signs of C7 (elbow extension)
20
Q
- Somatosensory loss in circle around neck
- Quadriparesis (weakness of all 4 extremities)
- UMN signs throughout
- Flexion and dorsiflexion weaker in legs
- Extension and supination weaker in arms
- PRONATOR DRIFT
- Clumsy fine finger movements
- Potential respiratory weakness
A
UPPER CERVICAL MYELOPATHY
21
Q
- Somatosensory abnormalities
- Loss of fine touch on left
- Loss of pain on right and at one level on left
- Motor abnormalities
- UMN signs on most of right side
A
UNILATERAL MYELOPATHY
(Brown sequard)
Note that pain is also gone ipsilaterally at lesion level due to loss of posterior horn
22
Q
- Unilateral loss of fine touch, conscious position sense and vibration
- Unilateral loss of all sensory modalities in top dermatome
- Urination and defecation maintained
A
POSTERIOR SPINAL ARTERY SYNDROME
(remember there are two - can be unilateral)
(remember that posterior horn lesion takes out everything one one side)
23
Q
- Bilateral UMN signs
- LMN signs in single myotome
- Bilateral loss of pain, gross touch and temperature
- Loss of control of urination and defecation
- Fine touch, conscious proprioception and vibration maintained
A
ANTERIOR SPINAL ARTERY SYNDROME
24
Q
Organization of Cerebellar inputs/outputs?
A
- Motor plan descends, synapses and decussates across pons –> contralateral cerebellum via middle cerebellar peduncle
- Actual position (unconscious) ascends just outside lateral motor column and enters cerebellum ipsilaterally via inferior cerebellar peduncle
- Adjustments exit superior cerebellar peduncle and decussate in the midbrain on the way to motor cortices via the contralateral thalamus
25
* Ataxia of gait and torso
* Ataxic (wide gait), can't walk straight line
* Can't stand or sit up straight (bad)
* Dysarthria
* Vertigo, nystagmus and nausea
* Heel to shin and finger to nose are normal
MEDIAL CEREBELLAR SYNDROME
Dysarthria due to incoordination of muscles of speech
26
* Ataxia / Ataxic gait
* Dysmetria (miss target) of left hand
* Intention tremor of left hand
* Failed heel to shin
* Dysarthria
* Vertigo, nystagmus, nausea
LEFT (IPSILATERAL) LATERAL CEREBELLAR SYNDROME
27
* Can't shrug right shoulder
* Can't turn head to left
RIGHT SIDE ACCESSORY NEUROPATHY
28
* Atrophy of left tongue
* Tongue deviates to left
LEFT SIDED HYPOGLOSSAL NEUROPATHY
29
* Dysarthria/dysphonia --\> No "ha" or "ka" sounds
* Dysphagia
* Half-assed gag reflex illicited on both sides
* Deviation of uvula to left
RIGHT SIDED VAGUS NEUROPATHY
Note: autonomic functions usually fine do to reduncy in contributions from both sides
30
* Somatosensory loss of left pharynx and posterior tongue
* Full gag reflex illicited only on right side
LEFT-SIDED GLOSSOPHARYNGEAL NEUROPATHY
31
* Unilateral weakness of muscles of upper and lower face
* Unilateral hyperacusis
* Abnormal taste sense
* Unilateral decreased lacrimation and salivation
FACIAL NEUROPATHY
32
* Unilateral somatosensory loss of face
* Weakness of chewing muscles
* Hyperacusis
TRIGEMINAL NEUROPATHY
33
* Ptosis (which muscle?)
* Weakness of eye elevation and adduction
* Dysconjugacy - Eye "Down and Out" at rest
* Mydriasis Aniscoria that worsens in the light
Oculomotor Neuropathy
Ptosis due to loss of SKELETAL MUSCLE innervation of Levator Palpebrae
Mydriasis and Light reflex due to loss of parasympathetics from the Edinger Westphal nucleus
34
* Can't fully abduct eye
* Diplopia and dysconjugacy
ABDUCENS NEUROPATHY
35
* Can't depress eye when adducted
* Can't intort eye when abducted
* Tilt head head down and to side (away from affected eye)
Trochlear Neuropathy
36
* Ptosis (which muscle)
* Miosis
* Aniscoria that is worse in dark
HORNER'S SYNDROME
Damage to sympathetic chain OR LATERAL BRAINSTEM!!!
Ptosis due to superior tarsal muscle
37
Rule of Fours?
* 4 MEDIAL structures that start with "M"
* Motor pathway --\> contralateral motor
* Medial lemniscus --\> contralateral fine touch, vibration and conscious proprio
* Medial longitudinal fasciculus --\> ?
* Medial Motor Nuclei (3, 4, 6 and 12)
* 4 "SIDE" structures (lateral) that start with "S"
* Spinocerebellar --\> Ipsilateral ataxia of extremities
* Spinothalamic --\> Contralateral pain and temperature
* Sympathetic pathway --\> ipsilateral Horner's
* Sensory Nucleus of CN 5 --\> ipsilateral loss pain and temperature on face
* 4 Cranial nerves in Medulla, 4 in Pons and 4 above the Pons
* Medulla = 9, 10, 11, 12
* Pons = 5, 6, 7, 8
* Midbrain = 3, 4
* 4 Motor nuclei medially all divide equally into 12
* 3, 4, 6 and 12 (1 and 2 don't count)
* 5, 7, 8, 9, 10, 11 are all lateral
38
* Left sided weakness of arms and legs
* Left sided loss of fine touch, vibration and proprio
* Right sided deviation of Tongue
* Left sided loss of pain, temp and gross touch of face?
* ARTERY?
RIGHT-SIDED MEDIAL MEDULLA SYNDROME
Branches of vertebral and anterior spinal arteries
"Trigeminothalamic Tract" does contralateral pain of face - doesn't fit into rule of 4, just know it
39
* Left-sided deviation of uvula
* Right-sided defects in afferent/efferent gag reflex
* Dysarthria, dysphagia, dysphonia
* Can't shrug right shoulder
* Can't turn head to left
* Right sided ataxia of limbs
* Left-sided loss of pain, temperature and gross touch
* Right-sided horner's syndrome
* Right-sided loss of pain, temp, gross touch of face
* ARTERIES?
Right-sided LATERAL MEDULLARY SYNDROME
Artery - PICA
40
* Left-sided motor weakness of arms and legs
* Left-sided loss of fine touch, vibration and proprio
* Right-sided inability to abduct eye
* ARTERY?
Right-sided MEDIAL PONTINE SYNDROME
Small arteries off Basilar Artery
41
* Left-sided loss of pain, temp and gross touch in arms and legs
* Right-sided ataxia of limbs
* Right-sided loss pain, temp and gross touch in face
* Right sided masseter muscle weakness
* Right sided upper and lower facial muscle weakness
* Right sided Horner's Syndrome
* Right sided hearing loss
* Nausea and vertigo
* ARTERIES?
Right-sided Lateral Pontine Syndrome
Arteries = AICA, branches from basilar, Superior Cerebellar arteries
42
* Loss of MOST voluntary motor functions
* Can't move or speak
* May be able to close eyelids or eye elevation
* ARTERY?
"LOCKED IN" SYNDROME
Bilateral lesion of basis pontis that spares the tegmentum
ARTERY = Basilar Artery
Takes out corticospinal and corticobulbar tracts and facial/trochlear motor nuclei (4 and 5)
Occulomotor (3) may be spared because its high
43
* Right-sided loss of fine touch, vibration and proprioception in arms and legs
* Right-sided loss of motor funciton in arms and legs
* Left Eye: Ptosis
* Left Eye: can't elevate, depress or adduct
* Eye "down and out"
* Left Eye: Mydriasis made worse in light
* ARTERY?
LEFT-SIDED MEDIAL MIDBRAIN SYNDROME
Posterior Cerebral arteries
44
* Right-sided loss of pain, temp and gross touch in arms and legs
* Right-sided ataxia
* Left-sided somatosensory loss of face
* Left-sided Horner's Syndrome
LEFT-SIDED LATERAL MIDBRAIN SYNDROME
45
* Pupil constricts when light is shown on other eye, but not when it receives light itself, PLUS...
* Monocular visual loss OR...
* Altitudinal visual loss (top or bottom half)
RETINOPATHY or OPTIC NEUROPATHY
Altitudinal may be due to superior retinal artery pathology
46
* Abnormal vision in the lateral vision fields of both eyes?
BITEMPORAL HEMIANOPSIA
Optic chiasm/pituitary tumor
47
* Left-sided loss of all somatosensory modalities in face, arm and leg?
Right-sided SUBCORTICAL SOMATOSENSORY LOSS
Small lesion in the thalamus can take out widespread INCOMING somatosensory information
Contrast to parietal cortex --\> arm and face OR leg
48
* Right-sided weakness in face, arms and legs?
* Dysarthria and dysphagia
SUBCORTICAL WEAKNESS
Small lesions in deep corona radiata, internal capsule, cerebral peduncle or upper basis pontis
49
Aprosodia vs. Aphasia
Receptive vs. Expressive
* Aphasia = inability to understand or produce the CONTENT of language
* DOMINENT LOBE
* Aprosodia = inability to understand or produce the TONE of language
* NON-DOMINENT LOBE
* Receptive = unable to comprehend
* Wernicke's area - lateral temporal lobe
* Expressive = unable to produce
* Broca's area - lateral frontal lobe
50
* Inability to see an entire side (left or right) of your visual field
vs.
* Inability to recognize objects, despite having full visual field capacity and acuity
"CONTRALATERAL HOMONYMOUS HEMIANOPSIA" = dysfunction of MEDIAL occipital lobe (primary visual cortices)
(may get macular sparing if occiptal pole is spared)
vs.
"Visual Agnosia" = dysfunction of LATERAL occipital lobe (association visual cortices)
51
* Fluent speech, though garbled with frequent paraphrasias
* Not frustrated and unaware of deficits - thinks others are speaking weird
* Impaired repetition
* What if repetition isn't impaired
RECEPTIVE ("WERNICKE'S") APHASIA
Wernicke's area is in Lateral Temporal Lobe
Deficit in language COMPREHENSION - why they don't notice their own deficits
If repetition wasn't impaired --\> "Transcortcial SENSORY aphasia"
52
* Receptive aphasia/aprosoida
* Contralateral SUPERIOR homonymous quadrantanopsia
LATERAL TEMPORAL LOBE SYNDROME
Involvement of Wernicke's area and inferior optic radiation
53
* Contralateral leg somatosensory abnormalities
MEDIAL PARIETAL SYNDROME
54
* Contralateral face and arm somatosensory abnormalities
* Contralateral astereognosis (paperclip) or agraphesthesia (letter on palm)
* Apraxia
* Contralateral inferior homonymous quadrantanopsia
* Anosognosia/Contralateral hemineglect
* WHEN?
LATERAL PARIETAL SYNDROME
Astereognosis/agraphesthesia/apraxia due to association cortex involvement
Visual due to superior optic radiation involvement
Contralateral hemineglect ONLY if in NONDOMINANT HEMISPHERE
55
* Contralateral leg UMN symptoms
* Apraxia
* Cognitive or emtional abnormalities
MEDIAL FRONTAL SYNDROME
Apraxia due to motor association cortices
56
* Diminished fluency with language
* Spoken, written, etc.
* Simplified words and grammar
* Frustrated, aware of inability to express themselves
* Impaired Repetition
* What if it isn't impaired?
EXPRESSIVE ("BROCA'S") APHASIA
Broca's area is in lateral frontal lobe
If no repetition difficulty --\> "Transcortical MOTOR Aphasia"
57
* Contralateral UMN symptoms of face and arm
* Dysphagia, Dysarthria
* Apraxia
* Ipsilateral gaze preference
* Unable to look to contralateral side
* Expressive aphasia/aprosodia
LATERAL FRONTAL SYNDROME
Apraxia due to motor association cortices
Gaze preference due to frontal eye fields
Aphasia due to Broca's
Aprosodia due to non-dominant hemisphere
58
* UMN weakness of left face and arm
* Dysarthria, dysphagia
* Somatosensory loss of all modalities of left face and arm
* UMN weakness and somatosensory loss of left leg
* Right Gaze preference
* Left sided homonymous hemianopsia
* Mixed aphasia OR Mixed aprosodia
* Maybe anosognosia and left-sided hemineglect
* Diminished motivation, attention or executive function
RIGHT-SIDED MIDDLE CEREBRAL ARTERY SYNDROME
May involve features of lateral frontal, parietal and/or temporal lobes, or subcortical cerebral hemisphere syndromes
Left leg involved due to subcortical axon involvement
Hemianopsia due to optic radiations in parietal and temporal lobes
Aprosodia/anosognosia/hemineglect only if lesion is in NONDOMINANT HEMISPHERE
59
* Right-sided leg UMN weakness and somatosensory loss of all modalities
* Apraxia
* Diminished motivation, attention or executive function
Left-sided ANTERIOR CEREBRAL ARTERY SYNDROME
Hits medial frontal and parietal lobes
Apraxia due to motor association cortex
60
* Homonomous hemianopsia with macular sparing
* Somatosensory loss of face, arm and leg
POSTERIOR CEREBRAL ARTERY SYNDROME
Hits medial occipital lobe and thalamus
NOTE: only lose somatosensory, internal capsule is not involved
