Motor Neuron Disease Flashcards
What is MND?
A cluster of degenerative diseases associated with selective loss of motor neurones in either the motor cortex, cranial nerve nuclei and anterior horns of the spinal cord
What age do people present with MND?
50-75
Is MND more common in males or females?
Males
What are the genes C9orf72 and SOD1 identified as causative for?
MND
What do 5% of people with MND go on to develop?
Frontotemoral dementia
What is the primary symptom of MND?
Muscle weakness
What muscles are commonly initially affected by weakness in MND?
Limbs (upper > lower)
How is MND distinguished from myasthenia gravis?
MND doesn’t affect the eyes
How is MND distinguished from MS and neuropathies?
No sensory loss or sphincter dysfunction
What are the 4 types of MND?
Amyotrophic lateral sclerosis
Progressive bulbar or pseudo-bulbar palsy
Progressive spinal muscular atrophy
Primary lateral sclerosis
What is the most common type of MND?
Amyotrophic lateral sclerosis
How does amyotrophic lateral sclerosis present?
Often starts in hands, spreads to all limbs and bulbar/thorax muscles
Muscle weakness (particularly hands, feet, shoulder)
Fasciculations
Stumbling gait
Drooling, dysarthria
Increased tone, spasticity
Does amyotrophic lateral sclerosis affect upper, lower or a mix of upper and lower motor neurones?
Mix
How does progressive bulbar or pseudo-bulbar palsy present?
Bulbar muscle weakness and subsequent limb involvement Drooling Dysphagia Dysarthria Wasted fasciculation tongue Emotional lability in pseudo-bulbar
Does progressive bulbar palsy affect upper, lower or a mix of upper and lower motor neurones?
Mix
How does progressive spinal muscular atrophy present?
Muscle weakness (particularly hands, feet, shoulder) Fasciculations Stumbling gait Drooling, dysarthria No increased tone or spasticity Absent or weak reflexes
Does progressive spinal muscular atrophy affect upper, lower or a mix of upper and lower motor neurones?
Lower only
How does primary lateral sclerosis present?
Predominantly limbs
Marked spasticity
Slow progressive tetraparesis (loss of all 4 limbs) and pseudo-bulbar palsy
No cognitive decline
What is progressive spinal muscular atrophy caused by?
Selective loss of anterior horn cells
What is primary lateral sclerosis caused by?
Loss of Benz cells in the motor cortex
How is MND diagnosed?
Clinical - El Escorial criteria
No scans or tests
What is the prognosis of MND?
Disease is usually fatal within 3 years
Usually as a result of respiratory failure or aspiration
What are the treatment options for MND?
Riluzole Analgesia Anticholinergic (for drooling) Baclofen or other muscle relaxant (for spasticity) Ventilator when breathing difficult Speech therapy, OT, dietitian
What is riluzole?
An Antiglutamate drug that prolongs life by about 3 months
Not always wanted
