what is mixed UMN and LMN motor neurone disease also known as?
amyotrophic lateral sclerosis
what is the name for pure UMN motoneurone disease?
primary lateral sclerosis?
what is the name for pure LMN motoneurone disease?
progressive muscular atrophy
which motoneuron is affected in pseudobulbar palsy?
which motoneuron is affected in bulbar palsy?
where does UMN originate and end?
motor region of cerebral cortex ie PMC
: synapses in brainstem (corticobulbar tract) or spinal cord (corticospinal tract)
where is the cell body of LMN? where do LMN axons travel and then synapse?
: anterior horn of grey matter or CN nuclei
: cranial /spinal nerves to the muscle fibre
what is the differential diagnosis for any LMN lesion? eg wasting (6 marks)
anterior horn cell
is anterior horn cell part of LMN or UMN?
what are the 3 main primary diseases of motor neurones (ie anterior horn cell disease)?
: MND, spinal muscular atrophy
give eg of spinal cord pathology that can affect anterior horn cells?
: infarction eg anterior spinal artery
: syringomyelia, tumour
if you think there is a LMN sign eg muscle wasting, what 3 questions need to be asked to get to diagnosis?
1. numbness/tingling/pain? (sensory abnormalities)
3. UMN signs?
if there IS numbness/tingling or pain, what does that rule out?
what is MND?
relentless degeneration of both UMN and LMNs
what is age of onset in MND?
late middle age: 50s
what is most common cause of death in MND?
respiratory failure or pneumonia (aspiration)
what % of MND is familial and which genetic abnormality?
what 4 muscles/nervous parts does MND spare?
which 2 treatable causes have to be excluded before diagnosing MND?
pure motor neuropathy
if suspect MND, which 3 tests need to be done and why?
1. nerve conduction studies
: exclude a neuropathy
: confirm DENERVATION and show fasciculations in muscles not thought to be clinically affected
: exclude brain/bulbar/spinal cord pathology eg cervical spondylosis or cerebrovascular disease
what is rilozole? benefit?
only prolongs life by 3-4 months but no proven effect on disability or QOL