Motor deficits: Part 2 (MS, MND)

Question 1

What is MND (motor neuron disease)? Mean onset? Who does it affect more? Prognosis?

Answer 1

Refers to a group of progressive neurological disorders that destroy motor neurons -the cells that control voluntary muscle activity.
E.g. speaking, walking, breathing, and swallowing.

Mean onset 50-60years

Male

Poor prognosis

Question 2

Examples of motor neurone disease?

Answer 2

ALS (amyotrophic lateral sclerosis)

Progressive bulbar palsy

Primary lateral sclerosis (PLS) (VERY RARE)

Progressive spinal muscular atrophy (VERY RARE)

Question 3

What is ALS (amyotrophic lateral sclerosis)?

Answer 3

Progressive neurodegenerative disease that attacks BOTH upper and lower motor neurons.

Results in muscle weakness and atrophy.

Question 4

Presentation of ALS (amyotrophic lateral sclerosis)?

Answer 4

• Fasciculations / Twitching
• Stiffness
• Weight loss / muscle atrophy
• Worsening fatigue
• Muscle weakness in facial and limb muscles
• Atrophy
• Hyper-reflexia
• Drooling
• Emotionally labile

NO SENSORY SYMPTOMS or LOSS OF BOWEL/BLADDER CONTROL.

NO PAIN or DIFFICULTIES WITH EXTRA-OCULAR MOVEMENTS.

Question 5

Treatment of ALS (amyotrophic lateral sclerosis)?

Answer 5

Riluzole
Symptomatic tx
Speech language therapy
Psychological/Social work care

Question 6

What is Primary lateral sclerosis (PLS)?

Answer 6

Has upper motor neurone damage ONLY

Deficits ONLY in the limbs

Question 7

What is Progressive spinal muscular atrophy?

Answer 7

Has lower motor neurone damage ONLY

More often familial than other forms of MND

Question 8

What is Progressive bulbar palsy?

Answer 8

Pt primarily has weakness of muscles innervated by cranial nerves.

Question 9

Causes of MND (motor neuron disease)?

Answer 9

misfolding of the TDP-43 protein

inherited

mutation in the SOD-1 gene

Question 10

Presentation of MND (motor neuron disease)?

Answer 10

Affects both upper and lower limbs.

Upper motor neuron signs include:
- Spasticity
- Hyperreflexia
- Upgoing plantars

Lower motor neuron signs include:
- Fasciculations
- Muscle atrophy

Eye and sphincter muscles are generally spared until late in the disease course.

Question 11

Compare both upper and lower motor neuron signs?

Answer 11

BOTH upper and lower neuron lesion have:
- weakness

UPPER:
- ABSENT or MILD MUSCLE ATROPHY
- no fasciculations
- hyperreflexia
- increased tone

LOWER:
- muscle atrophy
- fasciculations
- reduced/delayed reflexes
- reduced tone

Question 12

IVx of MND (motor neuron disease)?

Answer 12

TFTs (exclude thyrotoxicosis syndrome)

Protein electrophoresis (rule out paraproteinaemias)

MRI of brain and spinal cord (assess lesions or cervical spondylopathy)

EMG and nerve conduction studies

Question 13

Management of MND (motor neuron disease)?

Answer 13

Supportive tx
Riluzole
Analgesia

Treat spasticity and contractures with baclofen and botox injections

Anticholinergics -manage drooling

Supporting feeding via an NG or PEG tube as bulbar disease progresses.

Discuss advanced care planning early in disease progression.

Question 14

What is multiple sclerosis? Who does it affect more? Mean onset?

Answer 14

A chronic, inflammatory, autoimmune disease of the CNS.

Characterised by the demyelination and axonal loss of neurons.

Females are more affected.

Mean onset age 30 years

Question 15

Causes of multiple sclerosis?

Answer 15

potential viral pathogens

CD4-mediated destruction of oligodendroglial cells and a humoral response to myelin binding protein are key features of the disease.

Question 16

Presentation of multiple sclerosis?

Answer 16

Symptoms depend on the affected area of the brain or spinal cord.

Patchy paraesthesia
Optic neuritis -loss of central vision and painful eye movements
Internuclear ophthalmoplegia
Subacute cerebellar ataxia
Spastic paraparesis (Lhermitte’s sign)

• Balance difficulties
• Urinary urgency, frequency, incontinence
• Constipation
• Sexual dysfunction
• Cognitive loss
• Debilitating fatigue

Question 17

How is multiple sclerosis classified?

Answer 17

Relapsing-remitting (pts return normal or near-normal function between attacks)

Secondary progressive (relapsing-remitting course that becomes steadily progressive)

Primary progressive (progressive from the onset, symptoms generally do not remit)

Transverse myelitis (demyelinating lesions
of the spinal cord which can associated be with MS
or independent of MS)

Question 18

Diagnosis of MS (multiple sclerosis)?

Answer 18

Clinical hx/examination

MRI (periventricular white matter lesions; looks bright white on scan)

Oligoclonal bands in the CSF

Question 19

Acute management of MS?

Answer 19

glucocorticoids

IV methylprednisolone (every 24 hours for 3 days)

Plasma exchange (if no response to glucocorticoids)

Check bloods and urine dip to rule out intercurrent infection.

Question 20

Chronic management of MS?

Answer 20

Long-term management of relapsing remitting MS:
- DMT (disease modifying therapies)
- symptomatic therapies

1ST LINE:
- beta-interferon OR glatiramer

New oral agents such as dimethyl fumarate, teriflunomide and fingolimod.

Biologics such as natalizumab and alemtuzumab.

Symptomatic therapies include:
- Physiotherapy
- Baclofen and Botox for spasticity
- Modafinil and exercise therapy for fatigue
- Anticholinergics for bladder dysfunction
- SSRIs for depression
- Sildenafil for erectile dysfunction
- Clonazepam for tremor