MND

Question 1

What are the types of MND?

Answer 1

amyotrophic lateral sclerosis- most common
bulbar palsy
Primary lateral sclerosis-UMN
muscular atrophy-LMN

Question 2

What is the pathology f MND?

Answer 2

This is a degenerative condition that affects motor neurons, namely the anterior horn cells of the spinal cord and the motor cranial nuclei. It causes lower motor neurone (LMN) and upper motor neurone (UMN) dysfunction, leading to a mixed UMN/LMN picture of muscular paralysis, usually with LMN signs predominating

Question 3

What are the symptoms of MND?

Answer 3

Usually starts with upper limb onset symptoms. eg wrist drop, wasting, fasiculations, difficulty manipulating objects.
In lower limb may be tripping, gait problems, foot drop,
But can also be bulbar eg wasting tongue, speech slurred, dysphagia and respiratory symptoms.
Progressive weakness
cognitive decline may be present

Question 4

What are LMN signs?

Answer 4

Weakness, atrophy, fasciculations and hyporeflexia.

Question 5

What are UMN signs?

Answer 5

Weakness predominating in the arm extensors and leg flexors (pyramidal) with evidence of hypertonia, hyper-reflexia and upgoing plantar responses; the bulbar muscles may also show spasticity with an exaggerated jaw jerk.

Question 6

What investigations can be done for MND?

Answer 6

EMG, nerve conduction studies, CT/MRI, B12&folate
The diagnosis of motor neuron disease is clinical, but nerve conduction studies will show normal motor conduction and can help exclude a neuropathy.
EMG shows a reduced number of action potentials with increased amplitude.
MRI is usually performed to exclude the differential diagnosis of cervical cord compression and myelopathy
other tests are to rule out neuropathies

Question 7

What is the management for MND?

Answer 7

positive pressure ventilation, riluzole, diazeam for cramps, antidepressants,

Question 8

most common sx of MND

Answer 8

here are a number of clues which point towards a diagnosis of motor neuron disease:
fasciculations
the absence of sensory signs/symptoms
the mixture of lower motor neuron and upper motor neuron 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