Lower motor neuron conditions

Question 1

What are they key parts of the LMN tract to think about when coming up with differentials

Answer 1

Anterior horn cell
Roots/plexus
Peripheral nerves
NMJ
Muscles

Question 1

Pathologies which affect the anterior horn cell and how to distinguish between the two

Answer 1

Motor neuron disease - affects the anterior horn cell and also the upper and lower motor neurons, progressive wasting

Question 2

Features of MND

Answer 2

No loss of sensation
Progressive asymmetrical weakness and muscle wasting
Frontal lobe dementia in 3-5 percent of patients

Question 3

What are some cranial nerve features of motor neuron disease?

Answer 3

Speech - dysarthria
Jaw jerk (CN 5)- absent (bulbar) or brisk (pseudobulbar)
Eye movements

Bulbar

Question 4

What is bulbar

Answer 4

Lower motor neurons from the medulla - cranial nerves 9, 10, 11 and 12

Question 5

What is

Answer 5

Pain
Paralysis
Meningitis