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Flashcards in Localising Lesions Deck (80):
1

what are movement disorder features arise from lesions in the corticospinal/ pyramidal tracts

pyramidal/ UMN features:

pyramidal weakness (corticospinal distribution: hemiparesis, quadriparesis, paraparesis, monoparesis, faciobrachial)
spascticity

2

what are the types of movement disorders that arise from lesion in the basal ganlgia

(extrapyramidal)
hyperkinetic
- dystonia
- tics
- myoclonus
- chorea
- tremor

hypokinetic (rigidity and bradykinesia)
- parkinsonism
- parkinson's disease

3

what movement disorders arise from the cerebellum

ataxia

4

what makes up the peripheral nervous system

spinal nerve
root
plexus
peripheral nerves

5

what are the features of focal weakness

in distribution of peripheral nerve or spinal root
hemi-distribution (one side of body)
pyramidal distribution

6

what is pyramidal distribution weakness

where the extensors are weaker in the arms and the flexors are weaker in the legs

7

what are the features of non focal weakness

generalised
predominantly proximal or distal
if truely generalised will include bulbar motor function

8

UMN weakness:
distribution

corticospinal
-hemiparesis
-quadriparesis
-paraparesis
-monoparesis
- faciobrachial

9

LMN weakness:
distribution

generalised
predominantly proximal, distal or focal
no preferential involvement of corticospinal innervated muscles

10

UMN weakness:
Sensory loss

central pattern

11

LMN weakness:
Sensory loss

-can be none
-glove
-stocking
-peripheral nerve or root distribution

12

UMN weakness:
-deep tendon reflexes
-superficial reflexes
-pathological reflexes

deep- increased (unless very acute= flaccid)
superficial- decreased
pathological- increased

13

LMN weakness:
-deep tendon reflexes
-superficial reflexes
-pathological reflexes

deep- normal/ decrease
superficial- normal
pathological- normal

14

what are the superficial reflexes

plantar
gag/ swallow
cremasteric
corneal

15

what are the pathological reflexes

babinski (upward plantar, fanning and hyperextension of the toes), hoffmans etc

16

UMN weakness:
sphincter function

sometimes impaired

17

LMN weakness:
sphincter function

usually normal (except in cauda equina)

18

UMN weakness:
muscle tone

increased

19

LMN weakness:
muscle tone

decreased/ normal

20

UMN weakness:
muscle bulk

sometimes hypertrophy

21

LMN weakness:
muscle bulk

wasting

22

UMN weakness:
other CNS signs?

possibly

23

LMN weakness:
other CNS signs?

no

24

increased tone, brisk reflexes, pyramidal/ corticospinal pattern of weakness (= weak extensors in the arm, weak flexors in the legs) = ?

upper motor neurone pattern

25

wasting, fasciculation, decreased tone, decreased or absent reflexes, flexor plantars = ?

lower motor neurone pattern

26

what are the features of muscle disease

wasting (usually proximal)
decreased tone
decreased/ absent tendon reflexes

27

what are the features of NMJ weakness

fatiguable weakness
normal/ decreased tone
normal reflexes
NO SENSORY SYMPTOMS

28

what are the features of functional weakness

no wasting
normal tone
normal reflexes
erratic power
non anatomical loss

29

what causes UMN weakness

acute stroke syndromes
space occupying lesions
spinal cord problems

30

what weakness results from a hemispheric lesion

contralateral pyramidal weakness in face, arm, leg

31

what results from a parasagittal frontal lobe lesion

paraparesis

32

what UMN weakness results from a spinal cord lesion

pyramidal weakness below the level of the lesion
if cervical spine- arms and legs
if thoracolumbar- legs

33

what part of spinal cord do lower motor neurones attach to

anterior horn

34

what can cause a lower motor neurone lesion in the anterior horn cells

motor neurone disease
spinal muscular atrophy
lead poisoning, poliomyelitis etc

35

what are the two patterns of lower motor lesions in peripheral nerves

symmetrical (often length dependant):
- polyneuropathy with weakness and sensory symptoms: can be complication of diabetes, alcohol, metabolic insults

mononeuropathy:
-result of nerve compression (carpal, ulnar tunnel, radial neuropathy) or
-mononeuritis multiplex (asymmetric polyneuropathy) (occurs in diabetes or vasculitis)

36

what are the features of a median nerve mononeuropathy

thumb abduction paresis
thenar atrophy
sensory loss - thumb, second, third fingers, lateral 1 half of fourth finger

e.g. carpal tunnel syndrome

37

what are the features of a ulnar nerve mononeuropathy

finger and thumb adduction paresis
sensory loss- fifth and medial one half of fourth finger

38

what are the features of a radial nerve mononeuropathy

wrist, thumb and finger extension (wrist drop)
brachioradialis DTR lost
sensory loss on dorsum of hand

e.g. saturday night palsy

39

what are the features of a femoral nerve mononeuropathy

knee extensor paresis
loss of quads DTR
sensory loss over anterior thigh and medial calf

40

what are the features of a sciatic nerve mononeuropathy

ankle dorsiflexions and plantarfelxion paresis (flail ankle)
loss of achilles DTR
sensory loss on buttock, lateral calf, most of foot
e.g. caused by herniated disc

41

what are the features of a fibular nerve mononeuropathy

ankle dorsiflexion and evertors paresis (foot drop)
sensory loss on dorsum of foot and lateral calf
e.g. foot drop

42

what do NMJ disorder occur in

acetylecholine receptor antibodies mediated myasthenia gravis:
-ocular/ generalised

inhibition of acetylcholinesterase by organophosphate poisoning

lambert-eaton paraneoplastic syndrome
-interference with presynaptic calcium channel function

43

what can cause muscle disorders

inflammatory
endocrine (e.g. hypothyroidism, cushings, electrolyte abnormalities)
metabolic disorders
durgs and toxins
infections
rhabdomyelisis

44

shoulder abduction:
name the
-muscle
-nerve
-nerve root

deltoid
axillary
C5

45

elbow extension:
name the
-muscle
-nerve
-nerve root

triceps
radial
C7

46

finger extension:
name the
-muscle
-nerve
-nerve root

extensor digitorum
posterior interossues (radial)
C7

47

index finger abduction:
name the
-muscle
-nerve
-nerve root

first dorsal interosseus
ulnar
T1

48

hip flexion
name the
-muscle
-nerve
-nerve root

iliopsoas
femoral
L1,2

49

knee flexion
name the
-muscle
-nerve
-nerve root

hamstrings
sciatic
S1

50

ankle dorsiflexion
name the
-muscle
-nerve
-nerve root

peroneals
common peroneal and sciatic
L4,5

51

great toe dorsiflexion
name the
-muscle
-nerve
-nerve root

extensor hallucis longus
common peroneal
L5

52

what roots innervate the ankle DTR

S1,2

53

what roots innervate the knee DTR

L3,4

54

what roots innervate the biceps DTR

C5,6

55

what roots innervate the triceps DTR

C7,8

56

what does stocking (and later glove) sensory loss suggest

length dependent neuropathy

57

what is length dependent neuropathy

a polyneuropathy= it is the longest nerve-fibers that are most at risk, while the shorter
nerve-fibers are less affected. In brief, polyneuropathy is a "length-dependent" neuropathy. Because the
longest nerve-fibers in the body are those that run from the lower back to the feet, in typical cases of
polyneuropathy the first part of the body to become weak or numb is the feet.

58

what does a sensory level loss suggest

spinal cord lesion

59

what does hemianaesthesia suggest

contralateral cerebral lesion

60

what does dissociated sensory loss suggest (loss of spinothalamic (temp and pain) but reserved dorsal column (vibration, light tough, proprioception)

hemi cord damage (anterior spinal artery syndrome, brown sequard, syringomyelia)

61

what are the cerebellar signs

gait is broad-based and unsteady
Intention tremor / ataxia is assessed in the arms by finger-nose test and in the legs by knee-heel testing. Tremor gets exaggerated the nearer the target
Dysdiadochokinesis: clumsy fast alternating movements
Nystagmus and dysarthria are additional features of cerebellar disorders

62

what are extrapyramidal symptoms/ parkisonism

Bradykinesia, Rigidity, resting tremor, impaired gait and posture
Hypomimia
Hypophonia
Reduced arm swing, stooped posture, small steps, festination, turning en bloc
Impaired postural reflexes
Asymmetry in PD, symmetry in drug induced or atypical PD

63

what is the role of the frontal lobe

generates novel strategies and has executive functions. It enables self-criticism and trying again

Orbitofrontal cortex: response to primitive stimuli (hunger, thirst, sexual function) damage causes disinhibition
Dorsolateral prefrontal cortex: response to external stimuli (executing work resposnibilities)
Cingulate gyrus and dorsomedial frontal lobe: motivation, damage causes abulia (lack of will) or even akinetic mutism

64

what does the prefrontal cortex connect to

other association cortices, basal ganglia, limbic system, thalamus and hippocampus

65

what symptoms can arise from damage to the frontal lobe

Personality dysfunction
Paraparesis
Paratonia
Grasp reflex
Frontal gait dysfunction (magnetic gait)
Cortical hand
Seizures
Incontinence
Visual field defects (anterior visual pathway incl optic chiasms are beneath frontal lobe)
Expressive dysphasia (Broca’s area is in the dominant frontal lobe)
Anosmia (olfactory pathway is beneath frontal lobes)

66

what symptoms can arise from temporal lobe disorders

Memory dysfunction especially episodic memory
Agnosia (visual and sensory modalities in particular)
Language disorders receptive dysphasia (Wernicke, dominant hemisphere)
Visual field defects (congruous upper homonymous quadrantanopia)
Auditory dysfunction (Heschel’s gyrus, as hearing is represented bilaterally, deafness is not a cerebral feature)
Limbic dysfunction
Temporal lobe epilepsy

67

what symptoms can arise from damage to the parietal lobe

Visual field defect (congruous lower homonymous quadrantanopia)
Sensory dysfunction (visual and sensory modalities in particular)
Gerstmann’s syndrome (disease of the dominant angular gyrus, part of the inferior parietal lobe): Dysgraphia, left-right disorientation, finger agnosia, acalculia
Dyspraxia
Inattention (non-dominant angular gyrus)
Denial

68

what is the treatment protocol for parkinsons

Symptomatic treatment with Levodopa replacement or dopamine agonist
Multidisciplinary team management including Speech and language, OT, PT, exercise
For selected patients deep brain stimulation (subthalamic nucleus, globus pallidus int)

69

how does levodopa work

crosses the blood brain barrier while dopamine does not. Levodopa is then converted to dopamine in the brain while peripheral break down is prevented by the addition of ‘inhibitors of aromatic amino acid decarboxylase (carbidopa). Thus a carbidopa/levodopa formulation is often prescribed.

70

name some dopamine agonists used in PD

pramipexole, ropinirole, and bromocriptine

71

what other drugs can be used in PD

MAO-B inhibitors such as selegiline and rasagiline can improve symptoms in patients with mild disease (as monotherapy) as well patients already on levodopa.
Anticholinergics such as trihexyphenidyl or diphenhydramine (Benadryl) aim to combat tremor, but usually cause severe side effects
Amantadine blocks NMDA receptors and has a mild attenuation of resting tremor and dystonia. May alleviate levodopa induced dyskinesias.

72

is PD usually symmetrical or asymmetrical

asymmetrical

73

what does failure to respond to even high doses of levodopa mean in PD

suggests it is not idiopathic PD

74

what can levodopa cause in PD

dyskinesias

75

what is primary lateral sclerosis

a presentation of MND
pure upper motor neurone syndrome

76

what imaging for stroke

MRI T1/T2 and FLAIR images to identify old lesions and lesions of non-vascular origin
Diffusion weighted images (DWI) to identify new ischemic lesions (hyperintensities)

T2 to identify bleeds and microbleeds

Perfusion-weighted images (PWI) may be useful to identifies brain areas at risk of ischemia
CT brain: hyperintenisities – bleed, subtle ischemic signs in the acute phase of stroke (may be normal, early signs: loss of limits of lentiform nucleus, poor grey white matter differentiation, loss of insular ribbon)

77

what are the features of a lacunar syndrome

No visual field defect
No new higher cortical or brainstem dysfunction
Pure motor hemiparesis, or pure sensory deficit of one side of the body, or sensorimotor hemiparesis or ataxic hemiparesis (dysarthric clumsy hand syndrome or ipsilateral ataxia with crural hemiparesis)
At least 2 of the 3 areas (face, arm, leg) should be involved in its entity

78

what are the symptoms of a posterior circulation syndrome (stroke)

any one of:
Cranial nerve palsy
Unilateral or bilateral motor or sensory deficit
Disorder of conjugate eye movements
Cerebellar dysfunction
Homonymous hemianopia
Cortical blindness

79

what are the symptoms of a total anterior circulation syndrome (stroke)

Hemiplegia and homonymous hemianopia contralateral to the lesion, and
Either aphasia or visuospatial disturbances
+/- sensory deficit contralateral to the lesion

80

what are the symptoms of a partial anterior circulation syndrome

One or more of unilateral motor or sensory deficit, aphasia or visuospatial neglect (with or without homonymous hemianopia)
Motor or sensory deficit may be less extensive than in lacunar syndromes