MND Flashcards
Common clinical features
- asymmetric limb weakness
- mixture of UMN and LMN signs
- wasting of the small hand muscles/tibialis anterior
- fasciculations
What parts of the body are not affected by MND?
- external ocular muscles
- cerebellum
- abdominal reflexes
- sphincter dysfunction not affected till v late
MND diagnosis is clinical, but what investigations can be used to rule out other causes
Nerve conduction studies show normal motor conduction
=> exclude neuropathy
Electromyography shows a reduced number of action potentials with increased amplitude
MRI can exclude cervical myelopathy
After what age does MND normally present?
> 40y
Name the 3 common patterns of MND
Amyotrophic Lateral Sclerosis (ALS)
Progressive Muscular Atrophy
Bulbar palsy
What oral medication is used for MND?
Riluzole
- prevents stimulation of glutamate receptors
- used mainly in ALS
- prolongs life by ~3 months
What respiratory care is important for MND patients
non-invasive ventilation (usually BIPAP) is used at night
How is nutrition delivered to MND patients with dysphagia?
percutaneous gastrostomy tube (PEG)
3 Year prognosis in MND
50% of patients die within 3 years
LMN signs in arms and UMN signs in legs
gene responsible lies on chromosome 21 and codes for superoxide dismutase
Amyotrophic Lateral Sclerosis
What pattern of MND has only UMN signs
Primary lateral sclerosis
What pattern of MND has only LMN signs, affecting distak muscles first before proximal?
Progressive muscular atrophy
Palsy of the tongue, muscles of chewing/swallowing and facial muscles due to loss of function of brainstem motor nuclei
This subtype carries the worst prognosis
Progressive bulbar palsy