L08: Disorders of the Lower motoneurone Flashcards
What is a motor unit
The minimal functional unit of the motor system
What is the motor unit made of
- upper motoneurone
- Lower motoneurone (alpha)
- skeletal muscle (extrafusal muscle)
When does LMN signs present
When the lower motoneurone becomes damaged
What are the three anatomical damages that can occur to give LMN signs
- damage to Lower motoneurone
- damage to neuromuscular junction
- damage to skeletal muscle
What does innervation mean
The supply to a neurone or muscle
What does denervation mean
Damage to a neurone
What does re-innervation mean
Repair to a neurone
If the cell body of a neurone is damage is there a chance of re-innervation
No the neurone dies
What is poliomyelitis
Damage to the cell body of the lower motoneurone as a result of virus infection
What is Guillain barre syndrome
De-myelination of the axon of the lower motoneurone
What is diabetic neuropathy
Demyelination of the Lower motonuerone
What is motoneurone disease
When the motoneurone undergoes apoptosis
What are the variant of motoneurone disease
- both the upper and lower motoneurone undergoes cell death = progressive supranuclear
- only the lower motoneurone undergoes cell death
Which motoneurones do not undergo apoptosis
- motoneurone that supplies the anal spinchter
- motorneurone that supplies the eye lid (extraocular muscle)
What is botulinum toxin
Depletion of neurotransmitters in the pre-synpatic terminal due to non well preserved tin cans
