Neurological Syndromes in Small Animals

Question 1

What are the 5 main Neurological Syndromes in small animals?

Answer 1

1) Myopathic and Neuropathic Syndromes
2) Spinal Cord Syndromes: cervical, cervicothoracic, thoracolumbar, lumbosacral
3) Brain Syndromes: cerebral, pontomedullary, midbrain, vestibular, cerebellar
4) Multifocal Syndrome
5) Paroxysmal Syndrome

note: these syndromes can be used to localize a lesion in the neurological system

Question 2

What are the clinical signs associated with Myopathic Syndrome?

Answer 2

• Generalized weakness
• Exercise intolerance
• Stiff, stilted gait
• Localized or Generalized Muscle atrophy
• Generalized muscle hypertrophy
• Dimple contracture
• Muscle pain on palpation
• Limited joint movement

Question 3

What is the definition of Lower Motor Neuron?

Answer 3

The efferent neuron of the PNS that connects the CNS with the muscle to be innervated. The cell body in CNS axons project into the PNS via spinal nerves or cranial nerves

“the worker”

Question 4

What is the definition of Upper Motor Neuron?

Answer 4

The system that is confined to the CNS and is responsible for the initiation of voluntary movement, the maintenance of muscle tone for support of the body against gravity and the regulation of posture

“the manager”

Question 5

What is the definition of myopathy?

Answer 5

Disease relating to the muscle

Question 6

What is the definition of neuropathy?

Answer 6

Damage or dysfunction to one or more nerves

Question 7

What are the clinical signs associated with Neuropathic syndrome of the Motor neurons?

Answer 7

• Generalized weakness
• Flaccid paresis/ paralysis
• Neurogenic muscle atrophy: marked muscle loss
• Reduced/ absent reflexes and muscle tone

Question 8

What are the clinical signs associated with Neuropathic syndrome of the Sensory neurons?

Answer 8

• Decreased pain response (hypalgesia) or sensation (hypaesthesia)
• Proprioceptive deficits
• Abnormal Sendation/ sensitivity of the face, trunk, limbs
• Self-mutilation
• Reduced/ absent reflexes without muscle atrophy

Question 9

What are the clinical signs associated with Neuropathic syndrome of the autonomic neurons?

Answer 9

• May be seen alone or in combination with sensorimotor neuropathies
• Anisocoria/ or dilated pupils
• Decreased tear production
• Decreased salivation
• Bradycardia

Question 10

Define Tetraparesis

Answer 10

Reduced voluntary motor function of all 4 limbs (sub-divided into ambulatory or non-ambulatory)

Question 11

Define Tetraplegia

Answer 11

Total absence of voluntary motor function in all 4 limbs

Question 12

Define Paraparesis

Answer 12

Bilateral motor dysfunction in pelvic limbs

Question 13

An animal presents with paresis of the limb associated with acute onset of severe muscle atrophy. Upon limb flexion and extension there is little to no resistance, also there is little to no spinal reflexes
Is this UMN or LMN involvement?

Answer 13

LMN

Lower Motor Neuron

Question 14

An animal presents with paresis of the limb associated with chronic onset of muscle atrophy from not using the limb. Upon limb flexion and extension there is slight resistance, also there is normal spinal reflexes/ exaggerated
Is this UMN or LMN involvement?

Answer 14

UMN

Upper Motor Neuron

Question 15

Which nerves supply the brachial plexus and thus thoracic limb?

Answer 15

C5 - T1

Question 16

Which nerves supply the sacral plexus and thus pelvic limb?

Answer 16

L4 - S4

Question 17

Define Flaccid or LMN paresis/ paralysis

Answer 17

Reduced or absent spinal reflexes in one or more limbs

Question 18

Define Spastic or UMN paresis/ paralysis

Answer 18

Normal or increased spinal reflexes in one or more limns

Question 19

Define “Nerve Root Signature”

Answer 19

Pain apparent on palpation or traction of the limb due to a lesion irritating the nerve roots (e.g. slipped discs)

Question 20

Cervical Syndrome includes which spinal cord segments?

Answer 20

C1 - C5

Question 21

A dog presents with:

• Spastic paresis/ paralysis in all four limbs
• Normal to increased reflexes and muscle tone in all limbs
• Postural reaction deficits in limbs
• Has cervical muscle spasms, pain and rigidity
• Has urinary incontinence
• Nerve Root Signature

This is suggestive of which neurological syndrome?

Answer 21

Cervical Syndrome

Question 22

Horner’s Syndrome can sometimes be seen on which neurological syndromes?

Answer 22

Cervical Syndrome

Cervicothoracic Syndrome

Question 23

A dog presents with:

• Weakness/ paralysis in all four limbs
• Depressed reflexes and flaccid muscle tone with muscle atrophy in the Thoracic limbs
• Normal/ increased reflexes and tone without atrophy in the Pelvic limbs
• Postural reaction deficits in the TL limbs
• Hypanesthesia at the level of the lesion
• Hypaesthesia behind the lesion
• Paniculus reflex is depressed/ absent
• Has urinary incontinence

This is suggestive of which neurological syndrome?

Answer 23

Cervicothoracic Syndrome

Question 24

Cervicothoracic Syndrome includes which spinal cord segments?

Answer 24

C6 - T2

Question 25

Thoracolumbar Syndrome includes which spinal cord segments?

Answer 25

T3 - L3

Question 26

A dog presents with: - Spastic weakness/ paralysis of the pelvic limbs - Pelvic limb reflexes are normal - No atrophy in the pelvic limbs - Postural reaction deficits in the pelvic limbs - Increased local sensitivity at the level of, and behind the lesion - Has urinary incontinence - +/- Sciff-Sherrington posture: marked increase in extensor tone of thoracic limbs with severe thoracic cord lesion This is suggestive of which neurological syndrome?

Answer 26

Thoracolumbar Syndrome

Question 27

Lumbosacral Syndrome includes which spinal cord segments?

Answer 27

L 4 - S3 | all nerve roots that form the cauda equina: femoral, sciatic, obturator, pudendal, pelvic and coccygeal

Question 28

A dog presents with: - Flaccid weakness/ paralysis of the pelvic limbs + tail - Depressed pelvic limb reflexes and flaccid muscle tone - Postural reaction deficits in the pelvic limbs - Dilated anal sphincter - Hypaesthesia of the perineal region, pelvic limbs or tail - Has urinary incontinence - Has fecal incontinence - +/- Nerve Root Signature This is suggestive of which neurological syndrome?

Answer 28

Lumbosacral Syndrome

Question 29

What part of the brain is responsible for the generation of the gait?

Answer 29

- Pons + Medulla

Question 30

What part of the brain is responsible for fine-tuning movement, and thus controls unconscious proprioception?

Answer 30

Cerebellum

Question 31

What part of the brain is responsible for intellect and behaviour, along with voluntary movement?

Answer 31

- Cerebrum

Question 32

A dog presents with: - Normal gait - Altered mental status: apathy, depression, disorientation, lethargy, coma - Change in behaviour: loss of training, failure to recognize owner, aggression, hyperexcitability - Abnormal movements/ postures: pacing, wandering, circling, head-pressing - Postural reaction deficits in contralateral limbs - Visual impairment - Seizures This is suggestive of which neurological syndrome?

Answer 32

Cerebral Syndrome

Question 33

A dog presents with: - Symmetrical ataxia and preservation of strength - Dysmetric gait: altered rate, range or force of movement - Hypermetria: spastic, goose-stepping gait in all limbs, especially thoracic limbs - Intention tremor of the head and eyes - Broad-based stance - postural reactions delayed with exaggerated responses This is suggestive of which neurological syndrome?

Answer 33

Cerebellar Syndrome

Question 34

A dog presents with: - Head-tilt - Disorientation - Falling/ rolling - Nystagmus - Ventrolateral strabismus This is suggestive of which neurological syndrome?

Answer 34

Vestibular Syndrome

Question 35

Vestibular Syndrome can be divided into 2 distinct classifications, what are they?

Answer 35

Peripheral Vestibular disease/ syndrome: affecting the CN 8 Central vestibular disease/ syndrome: affecting the brain

Question 36

How can Central and Peripheral Vestibular Syndrome be differentiated?

Answer 36

It cant always be differentiated, as clinical signs are very similar, however Central Vestibular disease can cause a vertical and positional nystagmus But Peripheral Vestibular disease wont cause a vertical and positional nystagmus Central Vestibular disease may also present with cerebellar signs, mental depression and hemiparesis deficits Peripheral Vestibular disease wont cause the above

Question 37

A dog presents with: - Spastic paresis/ paralysis: all 4 limbs or contralateral to the lesion - Increased reflexes and muscle tone: in all 4 limbs or contraleteral - Postural reaction deficits: in all 4 limbs or contraleteral - Mental Depression + coma - Ipsilateral oculomotor deficits: VL strabismus, dilated and unresponsive pupils, normal vision, ptosis - Hyperventilation This is suggestive of which neurological syndrome?

Answer 37

Midbrain Syndrome note: pretty uncommon to get midbrain sydromes

Question 38

A dog presents with: - Spastic paresis/ paralysis: in all 4 limbs or ipsilateral limbs - Normal or increased reflexes and muscle tone in all 4 limbs - Multiple creanial nerve deficits: 5, 7, 9, 10, 12 - Irregular respiration - Mental depression This is suggestive of which neurological syndrome?

Answer 38

Pontomedullary Syndrome note: pretty uncommonly seen

Question 39

A dog presents with: - Altered mental status: disorientation, lethargy, coma - Normal gait - Abnormal temperature regulation - Abnormalities in appetite - Impaired vision - Endocrine disturbances: usually diabetes insipidus/ hyperadrenocorticism This is suggestive of which neurological syndrome?

Answer 39

Diencephalic Syndrome note: uncommonly seen Usually due to a pituitary tumour Impaired vision can be due to disturbances or damage to the optic chiasm

Question 40

What is a Multifocal Syndrome? | What is it usually caused by? (3)

Answer 40

``` When the animal is showing signs that reflect 2 or more syndromes These are usually due to: - Inflammatory diseases - Storage diseases - Intoxication ```

Question 41

What is a Paroxysmal Syndrome?

Answer 41

A group of sporadically occurring disorders that often have no discernible structural lesions within the nervous system Often normal between events = EPISODIC - Classic example would be seizures: cant figure out why the animal is having seizures and is normal between events

Question 42

What are some examples of Paraxysmal Syndromes? (7)

Answer 42

- Episodic seizures - Episodic sleep- narcolepsy - Episodic syncope - Episodic muscle cramping - Episodic weakness - Episodic tetany - Episodic myoclonus