Neurological Exam Small Animals Flashcards
Why do we perform a neurological examination?
Confirm that the problem is neurological (vs. musculoskeletal, etc)
Localize the lesion in the nervous system
Severity and extent of the lesion
Most lameness will be _______ (system) in origin?
Musculoskeletal
What is the 5/6 finger rule?
What are the 4 spinal cord segments?
C1-C5
C6-T2
T3-L3
L4-S3
What are the 4 intracranial structures? What kind of pathology is associated with disease of intracranial structures?
Cerebrum, Thalamic area, Cerebellum, Brainstem
Encephalopathy
What part of the body is “Myelopathy” associated with?
Spinal cord (C1-S3)
What is disease of a peripheral nerve called?
Neuropathy
What is disease of the NM junction called?
Junctionopathy
What is disease of the muscle called?
Myopathy
What is the name for the nerve plexus surrounding the forelimb?
Brachial plexus
What is the name for the nerve plexus surrounding the hind limb?
Lumbosacral alplexus
What are the 2 parts of the neurological examination?
Hands-off exam (observation) + history
Hands-on exam + physical examination
What are the tools required for performing a neurological examination on small animals?
What should you be observing about the patient during the “hands off” segment of the neurological exam?
What kinds of patients is this part of the exam particularly helpful for?
What part of the brain controls mentation/mental status?
Cerebrum and brainstem
What is the ARAS? What is it made of? What structure in the brain is it a part of? What is the function?
Ascending Reticular Activating System - neuronal projections from brainstem into the cerebral cortex (part of the reticular formation)
Function - arouse the cerebral cortex, to awaken the brain (cortex) to a conscious level, and to prepare the cortex to receive the rostrally projecting impulses from any sensory modality
What is the reticular formation? What is it made from? What is the function?
The reticular formation is a complex meshwork of brainstem nuclei and neurons that serve as a major integration and relay center for many vital brain systems to coordinate functions necessary for survival
What type of abnormality should you see with issues in the ARAS?
Abnormalities with mentation
What does activating the cerebral cortex achieve?
Awake state + level of consciousness
What are the 4 levels of mental status/consciousness (from least to most concerning)?
Normal
Obtunded
Stuporous
Comatose
Stuporous/Comatose mentation is most likely associated with disease in which part of the brain?
Brainstem > Forebrain
What is the difference between Obtunded and Stuporous mentation?
Obtunded - dulled or reduced level of consciousness/alertness, difficult to arouse
Stuporous - awakens once stimulated, otherwise in very dull/sleep-like state, VERY difficult to arouse
What do wide circles vs. tight circles indicate?
Wide circles = forebrain
Tight circles = vestibular system
Do patients circle toward or away from the side of the lesion? How can this be explained?
TOWARD the side of the lesion
If patient has LESION on RIGHT side of the brain, the nerve impulse decussates, so the patient cannot acknowledge the LEFT side of the body, leading to CIRCLING toward the RIGHT
What part of the brain is headpressing associated with?
Forebrain
What is hemi-neglect syndrome? What part of the brain is this abnormal behavior associated with?
How do you localize a lesion based on this condition?
Patient does not acknowledge half of their space (either right or left) due to forebrain lesion.
Patient with lesion in left forebrain will only acknowledge the left side of their world due to decussation of nerve impulses to the right.
Ex. patient with right forebrain lesion (decussates to the left) only eats the food in right side of bowl, leaves left side of the bowl full
What part of the brain is head tilt associated with?
Vestibular system
What is pleurothotonus?
Head turn and body turn
In pleurothotonus which way does the patient turn in association with the lesion? What part of the brain is pleurothotonus associated with?
Patient will turn TOWARD the side of the lesion
Associated with thalamocortex/forebrain
What type of stance is this? What part of the brain is this type of stance associated with?
Wide based stance
Cerebellum
What is this spinal conformation?