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Flashcards in Motor neurone disease Deck (14):

What is motor neurone disease?

untreatable and rapidly progressive neurodegenerative condition
-progressive motor poblems with both UMN and LMN features
-no sensory problems
-focal onset and continuous spread


What is the average survival time for motor neurone disease?

3 years


What is the genetic inheritance of motor neurone disorder

90% sporadic
10% inherited


When does MND usually present and what clinical symptoms and signs should make you think of motor neuron disease?

It rarely presents before 40 years

-the absence of sensory signs/symptoms*
-the mixture of lower motor neurone and upper motor neurone signs
-wasting of the small hand muscles/tibialis anterior is common

Other features
-doesn't affect external ocular muscles
-no cerebellar signs
-abdominal reflexes are usually preserved and sphincter dysfunction if present is a late feature


What are the five different types of MDN?

amyotrophic lateral sclerosis,

primary lateral sclerosis,

progressive (or spinal) muscular atrophy,

progressive bulbar palsy

pseudobulbar palsy


Amyotrophic lateral sclerosis - is this common? what signs are seen? In familial cases where is the gene responsible located?

50% patients

typically LMN signs in arms and UMN signs in legs

in familial cases the gene responsible lies on chromosome 21 and codes for superoxide dismutase


Primary lateral sclerosis - what signs are seen?

UMN signs only
-leg weakness and is found to have a relatively pure spastic parapesis


Progressive muscular atrophy:
What signs are seen?
Which muscles are affected?

LMN signs only
affects distal muscles before proximal
carries best prognosis


Progressive bulbar palsy
-what is a bulbar palsy?
-what are the signs/symptoms?
-F:M? what age

bulbar palsy is a lower motor neuron lesion of cranial nerve IX, X and XII
-slurring dysarthria
-F>M (60-80yrs)


Psuedobulbar palsy:
-what is a pseudobulbar palsy?

pseudobulbar palsy = upper motor neurone lesion of cranial nerve IX, X and XII
-increased gag/jaw jerk reflex
-spastic tongue
- palatal movement is absent
-spastic speech (monotonous/slurred/high pitch = donald duck)


How is MND diagnosed?
-clinically definitive
-clinically probable
-clinically possible

clinically - diagnosis of exclusion (after ix have ruled out other DDx)

-UMN and LMN signs in bulbar region + 2 or more spinal regions
-OR UMN and LMN signs in 3 spinal regions

-UMN and LMN in 2 or more spinal regions with some UMN signs rostral to LMN

-UMN and LMN in 1 spinal region
-LMN signs and 2 or more spinal regions
-LMN signs are found rostral to UMN signs


What UMN signs exist?

-pseudobulbar affect
-moderate weakness
-extensor (up going) plantar reflexes - babinski sign


What LMN signs exist?

-severe weakness
-muscle cramps
-muscle hypotonicity
-muscle atrophy


What is the management of MND?

specialist services: key worker, S+L, nutrition, respiratory needs

Riluzole: prevents stimulation of glutamate receptors, used mainly in amyotrophic lateral sclerosis, prolongs life by about 3 months

Respiratory care:
non-invasive ventilation (usually BIPAP) is used at night
studies have shown a survival benefit of around 7 months