Motor Disorders - Random Order!!!

Question 1

What is the presentation of “hemiparetic gait after stroke”?

Answer 1

Classically, see probelms with extensors of upper limb - so Flexed upper limbs and then problems with Flexion in lower extremities so see Extended Legs and circumduction of lower extremity

Question 1

What is a non-rhythmical, non-stereotypes, Hyperkinetic disorder?

Answer 1

Either Chorea or Myoclonus depending on speed

Myoclonus - SUPER fast

Chorea-medium fast

But both are neither rhythmical or stereotyped

Question 2

Treatments used in Essential Tremor?

Answer 2

First line agents - Propanolol (non-selective beta blocker) and Primidone (anticonvulsant)

Others include Anticonvulsants, botulinum or surgery/DBS of thalamus

Question 3

What are the other Parkinsonian Syndromes?

Answer 3

Tend to be related degenerative disorders that are more widespread:

1) Progressive Supranuclear Palsy = Early valls, Vertical Opthalmoglegia
2) Multiple System Atrophy = Parkinsonism + Ataxia + Dysautonomia (Shy-Drager)
3) Corticobasal Syndrome = Parkinsonism + Alien Limb phenomenon and Asymmetric motor signs

Question 3

What is the MAIn difference that you can see in tremor between Parkinson’s and Essential Tremor?

Answer 3

Parkinsons - Tremor maximal activation at REST!!!

ET: maximal activation with maintenance of posture or movement

Question 3

What is Dystonia?

Answer 3

Syndrome of sustained stereotyped movements and contractions that can lead to abnormal postures etc

Question 4

Describe the scale of movement characteristics from chorea to athetosis to ballismus

Answer 4

Chorea - brief movements, non-stereotyped, non-rhythmical, random distribution

More Distal > Proximal

Discontinuous

Athetosis - Chorea + Flowing continueous snake-like movements

Ballismus - wild flining and random movements

Proximal> Distal

Question 6

What is the mechanism for spasticity?

Answer 6

Disinhibition of Anterior Horn Cells becuase have interruption of Pyramidal Tract leading to increased excitation

Question 6

Distinguish PD from ET based on history alone?

Answer 6

PD - age of onset 55-65 and symptoms last for a few months prior to presentation, no family history and no response to alcohol

ET - variable age of onset, symptoms can last for years before presentation, Autosomal Dominant so runs in families, CALMS down with EtOH

Question 7

Upper Motor Syndrome - what you you typically see?

Answer 7

Contralateral Hemiparases if above the decussation and Ipsilateral if below

Weakness, Hyperreflexia, Babinksi, Clonus

Question 8

Clinical Features of HD?

Answer 8

Chorea, Dementia, Gait disorders

Affective disorders, behavioral disturbances, Psychosis, Dysarthria, Dysphagia

[Main cause of death is dysphagia]

Question 10

Pathophysiology of Parkinson’s Disease?

Answer 10

Degeneration of Nigral neurons leads to increase in excitability of Sub-Thalamic Nucleus and Globus Pallidus internal (main output from BG which increases inhibition on motor cortex)

Decreased Excitation of motor cortex from increased inhibition on Motor thalamus

Question 11

What does the term Spastic Quadraparesis and Parapesis refer to?

Answer 11

Spastic quadraparesis - UMN syndrome involving all 4 limbs but sparing face - refers to lesion involving cervical cord above C5

Spastic PArapesis - UMN syndrome involving both lower extremities and implies lesion of SC below cervical region enlargement

Question 12

What is the role of the cerebellum in movement?

Answer 12

Monitors ongoing movement and initiates new movement

ensures appropriate speed and accuracy of movements

Question 13

What are some drugs that can cause a presentation similar to parkinsons?

Answer 13

Anti-psychotics (especially those that block Da)

Anti-emetics - Metoclorpramide!!

Toxins like MTMP, Manganese and CO

Question 13

What are the Da agonists? What are they used for? Which one is a “rescue therapy”?

Answer 13

Work on Da receptor and used in Parkinson’s Disease

Pramipexoe, Ropinirole, Rotigotine

**Apomorphine - Acute Rescue therapy that starts right away but only lasts a short term

Question 14

What is the mainstay of treatment for PArkinson’s Disease and what is it given with and why?

Answer 14

L-Dopa, which is Da Precursor, given bc DA can’t cross BBB

Must be given with Peripheral Da-Decarboxylase Inhibitor Carbidopa so it’s kept in the L-Da form before crossing BBB

[if converted in periphery, circulating Da causes Nausea bc activates Area Postrema in medulla that doesn’t have BBB]

Question 16

What is a Rhytmical Hyperkinetic disorder?

Answer 16

Tremor = rhythmical ossilation of a body part

Question 17

Treatment for Dystonias?

Answer 17

Botulinum toxin into overactive muscles at sub-therapeutic doses to lightly block Ach release at the presynaptic junction and cause weakness

Question 18

Main cause of Acute Hemiballismus?

Answer 18

Stroke of Sub-Thalamic Nucleus

Question 19

What are the 3 main body parts that present with ET?

Answer 19

Upper Limbs, Head, voice

Question 20

What are the 4 drug treatments for Spasticity and their mechanisms of actoin?

Answer 20

Baclofen - enhances GABA-mediated inhibition at SC level

Benzos - enhance GABA inhibition at SC level

Tizanidine - A2 adrenergic receptor Agonist to inhibit excitatory sensory afferents TO the motor neurons

Botulinum Toxin - blocks release of Ach at Pre-synaptic Nerve Terminal in NMJ causing weaker responses at muscles

{3 act on the Anterior Horn and 1 acts on the muscles]

Question 22

Where does deep brain stimulation for Parkinson’s disease act in the brain?

Answer 22

GPi = Globus Pallidus interna

Sub-Thalamic Nucleus

Question 23

What are “Cerebellar Signs”?

Answer 23

Incoordination

Dysmetria - finger to nose test - can’t gauge accuracy of target

Dysdiadokinesia - rapid repetitive movements are slow and incoordinated

Ataxia - gait, heal to shin test; See BROAD BASE stepping

Dysarthria - scanning

Nystagmus and - **ocular overshoot dysmetria **

Question 25

What is a Non-rhytmical, Stereotyped Hyperkinetic disorder?

Answer 25

Either Dystonia (slow) or Tics (rapid)

Question 26

Distinguish PD from ET based on Physical Exam

Answer 26

PD - Max activation of tremor at rest, slower, “pill-rolling’ and UNILATERAL

• Hand, foot, chin, lips

Small hanwritting with no trumor

noticeably progressive with associated signs

_______________________________________________

ET: Max activation with posture and movement, faster, Flexion/extention morphology, BILATERAL

• hands, head and voice

Normal hanwritting but is tremulous

Not noticably progressive and no associated signs

Question 27

What are the different sustained stereotyped spasms seen in Focal Dystonias?

Answer 27

Blepharospasm - involuntary eye closure

Oromandibular

Cervical Dystonia - Torticollis - involuntary head turning

Laryngeal - involuntary vocal cord spasm (abduction - whispery; adduction - strangulation) = shouting/whisper better than speaking

Dystonic Writer’s cramp - Task specific musicians and writers

Question 28

What do you see in Lower Motor neuron syndromes?

Answer 28

weakness, reduced tone/bulk, less reflexes

Fasciculations

Ipsilateral problems

Question 29

Characteristic features of Parkinson’s Disease?

Answer 29

**Bradykinesia **

Involuntary tremors/RESTING tremor = Pill-rolling

**Cogwheel Rigidity **

bending forward, festinations

Small handwritting, decreased blink rate and facial expression

Freezing and robotic turning

Impaired postural righting reflexes - Fall risk!!

Shuffling gait; Can’t get out of chair or turn in bed

Long-term - see dementia

***STARTS UNILATERAL! **

Question 30

Genetics of Huntington’s Disease

Pathology?

Answer 30

**Autosomal Dominant and 100% Penetrant **

onset 20-40 but variable - randomly have childhood senescence and then see younger and younger in families

**CHROMOSOME 4 >40 Unstable Triple Repeat of CAG = Huntingtin gene **

-length of repeat inverseley related to age of onset

See Neuronal Loss and Gliosis in STRIATUM