The Neurological Exam Flashcards
What is necessary when performing the neurological exam?
Understanding of what each test is determining
Master each technique and interpretation of the results of that technique
What are the possible locations of lesions?
In the brain = forebrain, brainsterm and cerebellum
In the spinal cord = C1-5, C6-T2, T3-L3, L4-Cd
Neuromuscular
What is the aim of the neurological exam?
To determine if the animal is neurologically normal/abnormal and localise the lesion
What are the tools required to perform the neurological exam?
Room, chair, yoga mat, reflex hammer, haemostats, Q-tips, cotton balls, penlight, lens
What are the steps of the neurological exam?
Mentation, Posture, Gait, Postural reactions, Spinal reflexes, Cranial reflexes, Palpation, Nociception
How do you assess mentation?
Level and quality of consciousness
What spectrum is consciousness assessed on?
Alert, obtundation, stupor/semicoma or coma
What different elements of posture are assessed?
The head, the limbs and the body
What are the two abnormal postures of the head and what do they indicate?
Tilt = vestibular disease Turn = forebrain disease
What can limb posture tell you about neurological disease?
Wide based stance = proprioceptive loss
Narrow based stance = weakness
Decreased weight bearing = pain
What is a decerebrate posture?
Involuntary extension of upper extremities
Head arched backwards, front legs extended, back legs extended behind animal, no mentation
What is a decerebellate posture?
Neck and forelimbs extended, hindlimbs flexed, mentation ok
What is a Schiff-Scherrington posture?
Forelimbs rigid, hindlimbs flexed, mentation ok, spinal lesion at T3-L3
Why is gait analysis useful to assess?
Requires the integration of proprioceptive and motor systems
What do you need to ask when assessing gait?
Normal/abnormal
Which limb/limbs are affected?
Paresis/ataxia/lameness/combination
What is paresis?
Decreased voluntary movement
How do you differentiate between UMN and LMN paresis?
By assessing postural reaction, spinal reflexes and muscle tone
What does UMN paresis look like?
Muscle tone and spinal reflexes are normal to increased in limbs caudal to the lesion
Stride length is normal to increased but can be spastic
+/- ataxia
What is the clinical appearance of LMN?
Muscle tone and spinal reflexes are decreased in limbs with a reflex arc containing the lesion
Stride length is normal to decreased, stiff, bunny hopping +/- collapse
What is the definition of ataxia?
Incoordination
What are the three different types of ataxia?
Sensory, cerebellar or vestibular ataxia
What is sensory ataxia and how does it appear clinically?
Loss of sense of limb/body position
Wide based stance, increased stride length, swaying/floating gait, knuckling
What is cerebellar ataxia and how does it appear clinically?
Disorder of rate and range of movement
Hypermetria, intention tremor, postural tremor
What is the appearance of vestibular ataxia
Unilateral = falling/leaning/circling to one side and head tilt Bilateral = wide excursions of the head, +/- head tilt and crouched posture
What postural reactions are tested?
Paw positioning, hopping, wheelbarrowing, hemiwalking, placing and extensor postural thrust
What tendon reflexes are tested and where do they originate?
Biceps (C6-8), triceps (C7-T2), patellar (L4-6) and gastrocnemius (L6-S2)
Where do the flexor reflexes for the thoracic and pelvic limbs originate?
Thoracic = C6-T2 Pelvic = L6-S2
What can cause decreased to absent spinal reflexes?
Lesion within reflex arc
Physical limitation due to joint fibrosis/muscle contracture
Excitement/fear as muscles will have more tone
Spinal shock
What can cause exaggerated reflexes?
Lesion to UMN pathways cranial to the spinal cord segments tested
Excitement/fear as muscles will have more tone
Pseudohyperreflexia due to loss of antagonism
How do you test the optic nerve (CN II)?
Vision (obstacle course)
Menace response
PLR
Fundic examination
How do you test the function of CN III (oculomotor)?
PLR
How do you assess CN III, IV and VI?
Look for strabismus (eye position) and nystagmus (eye movement)
How do you assess CN V?
Facial sensation
Palpebral and corneal reflex
Tone of muscles of mastication
How do you assess CN VII?
Signs of facial paresis/paralysis/asymmetry
Palpebral reflex
Menace response
Schrimer tear test as autonomic innervation of lacrimal gland
How can you assess the function of CN VIII?
Cochlear branch by hearing
Vestibular = ataxia/head tilt, strabismus/nystagmus
How do you assess CN IX and X?
Gag reflex
How do you assess the function of CN XII?
Paresis/paralysis of the tongue, tongue atrophy/asymmetry, deviation of the tongue
What is light palpation used to detect?
Swelling or atrophy
What is deep palpation used to asses?
Pain
How do you assess different types of pain?
Perception of pain is in the forebrain
Superficial pain is the skin and deep pain is bone
Does limb withdrawal indicate pain?
No as withdrawal can still occur without pain detected as the reflex arc only hits the spinal cord and pain requires forebrain perception
What nerves could be affected if the menace response is negative?
II or VII
What nerves could be affected if the PLR is negative?
II or III
What nerves are affected if strabismus is present?
III, IV or VI
What nerves are affected if there is spontaneous nystagmus or absence of physiological nystagmus?
III, IV, VI or VIII
What nerves are affected if there is no palpebral reflex?
V or VII
What nerves are affected if there is no corneal reflex?
V or VI
What nerves are affected if there is no gag reflex?
IX or X
