Motor Neuron Disease Flashcards
What is MND
Umbrella term for progressive neurodegenerative diseases affecting the motor neurones
Describe the 4 main types of MND
- Amyotrophic lateral sclerosis - mc, typically LMN signs in arms and UMN signs in legs
- Progressive bulbar palsy - palsy of the tongue, muscles of chewing/swallowing and facial muscles
- Progressive muscular atrophy - LMN signs only, affects distal muscles before proximal
- Primary lateral sclerosis - UMN signs only
Which types of MND carries the best and worst prognosis
- Best: Progressive muscular atrophy
- worst: Progressive bulbar palsy
Give 3 RFs for MND
- Male >40
- FHx
- professional athletic activity
Give 4 signs of UMN lesions
- Hypertonia
- +ve Babinski sign
- Hyperreflexia
- Spasticity
Give 4 signs of a LMN lesion
- Fasciculations
- Muscle wasting
- Hyporeflexia
- Hypotonia
What effect does MND have on ocular muscles
eye movements are typically spared
Describe the presentation of amyotrophic lateral sclerosis
- Spastic unsteady gait
- Foot drop
- UMN + LMN signs
- Dysphagia and dysarthria
- wasting of the small hand muscles
- asymmetric Proximal muscle weakness
- Dyspnoea/ orthopnoea
(Progressive painless paralysis)
How is MND diagnosed
Clinical diagnosis - presence of UMN/LMN signs, disease progression and absence of any other aetiology
* nerve conduction studies - normal motor conduction
* EMG - reduced number of action potentials with increased amplitude
How is ALS treated
- Riluzole - slows progression (3m)
- Non-invasive ventilation (BIPAP at night)
- Supportive care
- percutaneous gastrostomy tube (PEG) - support nutrition
How does riluzole slow the progression of ALS
Sodium channel blocker that inhibits glutamate release protecting motor neurones
Give 2 complications of ALS
- Respiratory failure
- Aspiration pneumonia
What type of dementia is associated with MND
Frontotemporal dementia
