Neuromuscular Disorders and Peripheral Neuropathies Flashcards
The botulinum toxin prevents release of acetylcholine at the NMJ resulting in what type of paralysis?
(Progressive flaccid)
How do horses get botulism?
(Ingested of the pre-formed toxin, growth of the organism in a wound, and production of the toxin by the organism in the GI tract (aka toxicoinfectious form))
The toxicoinfectious form of botulism typically affects foal 1-2 months of age and is associated with a fairly rapid onset of what clinical signs?
(Stumbling, weak, toe dragging, and recumbency (recumbency results in dehydration and hypoglycemia bc they cannot nurse))
What is often the first sign of botulism in adult horses?
(Dysphagia)
Why may botulism horses present for colic?
(Bc botulism causes ileus)
How is botulism prevented?
(Vaccination, proper storage of feed, and taking care when using round bales)
What are the more common nerves to be injured in horses?
(Facial, suprascapular, and radial nerves)
Describe the following:
- Neuropraxia
- Axonotmesis
- Neurotmesis
- Neuropraxia (Bruising and inflammation of a nerve, this is transient, resolves in 3-6 weeks)
- Axonotmesis (Nerve crushing where the epineurium and perineurium remain intact)
- Neurotmesis (Whole nerve fiber is severed, distal segment will undergo Wallerian degeneration)
Denervated muscles lose 50% of their mass by two weeks, what can develop in chronic injuries that can prevent healing all together?
(Fibrosis of the affected muscles → failure to heal beyond 12 months has poor prognosis)
What are the main treatments used for acute nerve injuries?
(Anti-inflammatory therapy (NSAIDs, cold therapy) and physical therapy (passive ROM, exercise → helps develop compensatory mechanisms and strength))
What are etiologies for facial nerve paralysis?
(Traumatic compression over the facial crest, inflammation in the middle ear and/or guttural pouch, and brainstem dz)
Trauma to the suprascapular nerve prevents appropriate abduction/adduction (choose) of the limb?
(Adduction)
