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Flashcards in Gaitero - Neurology Deck (84):
1

Neurological Exam (6 steps)

1. Mental status
2. Gait / posture
3. CN exam
4. Postural reactions: Proprioception/Hopping
5. Spinal reflexes
- PL: Patellar / Withdrawal (flexor)
- TL: Withdrawal
- Cutaneous trunci, perineal
6. Palpation (back / neck pain)

2

3 goals of the neuro exam

1. Identify/confirm presence of a neurological problem
2. Localize the lesion within the nervous system
3. Others
 Assess severity/extension lesion  Prognosis

3

VITAMIN D stands for…

VASCULAR
INFLAMMATORY / INFECTIOUS
TRAUMATIC / TOXIC ANOMALOUS (congenital) METABOLIC
IDIOPATHIC
NEOPLASTIC / NUTRITIONAL
DEGENERATIVE

4

Spinal Cord Enlargements

There are two regional enlargements of the spinal cord for the innervation of the limbs:
· cervical intumescence C6-T2
composed of cord sections C6, C7, C8, T1, (T2)
· lumbosacral intumescence L4 to S3
composed of cord sections L4, L5, L6, L7, S1, S2, S3 (some say L5 to S1)

5

Intervertebral disc disease

Degenerative changes increase with repetitive compression (e.g. heavy lifting in flexion) or trauma (e.g. fall); degenerative changes may be asymptomatic

6

Where does the spinal cord terminate in large breed/small breed dogs & cats?

Large breed - L6
Small breed - L7
Cats - L7/S1

7

Canine Vertebral Formula

C-7, T-13, L-7, S-3

8

Spinal cord segmentation

Spinal cord divided in segments:
8 cervical
13 thoracic
7 lumbar
3 sacral
>= 2 caudal

9

3 types of ataxia

Proprioceptive
Cerebellar
Vestibular

10

Where is the LMN Cell body? Axon?

Ventral Grey horn
From PNS to muscle
Reflex motor activity

11

UMN Clinical signs

Paresis (weakness)
Decrease of inhibitory LMN reflex so spinal reflexes are increased or normal
Disuse mucle atrophy, increased muscle tone.
Usually proprioceptive ataxia

12

LMN Clinical signs

Paresis/paralysis
Decreased or absent reflex
Loss of muscle tone
Neurogenic muscle atrophy

13

Functional classification of the spinal cord (segments)

C1-C5
C6-T2
T3-L3
L4-S3

14

Extradural
Intradural-Extramedullary
Intramedullary

Outside the dura matter, but pushing pressure on the spinal cord
Inside the dura matter, but not in the actual cord
In the actual spinal cord

15

Clinical signs of spinal cord compression

1. Back/neck pain
2. Proprioceptive losses
3. Loss of motor/paresis
4. paralysis
5. loss of nociception (deep pain)

16

Differentials for acute myelopathies

Febrile cartilagonis embolism myleopathy
Spinal trauma
Intervertebral disc (IVD) herniation: extrusion

17

Annulus fibrosus

fibrous ring of intervertebral disk

18

Intervertebral disc (IVD) herniation: Extrusion vs. protrusion

Extrusion of mineralized nucleus pulposus into the vertebral canal (hansen type 1)- usually acute
Protrusion - usually chronic

19

Chondrodystrophic breeds/ages (w.r.t IVD herniation)

Daschunds, beagles, cockers, shih tzu (3-6 years old, rare < 2)

20

Location for IVD extrusion herniation

T11 - L3, cervical (uncommon to be T1-10;inter capital ligament)

21

IVD Extrusion diagnosis

Thoracic rads
Myelogram (CT)

22

IVD Extrusion treatment (surgical/when to use)

Surgical:
Thoracic:
Hemilaminectomy
Pediculectomy
Cervical: Ventral Slot
Use surgical if pain or neurological deficits

23

Hemilaminectomy

Remove part of a lamina of the vertebral arch in order to decompress the corresponding spinal cord and/or spinal nerve root.

24

pediculectomy

surgical removal of portions of vertebral pedicles at the level of the intervertebral foramen.

25

IVD Extrusion emergency

Loss of deep pain
Quick onset
Non-ambulatory (thoracic)
Tetraplegia (cervical)

26

IVD Extrusion treatment (conservative)

Strict cage confinement for 3-4 weeks
Pain killers (NSAIDs Opioids) +/-
First episode of pain without deficits (50% get better)

27

IVD Extrusion treatment (what not to use)

Never use NSAIDs + steroids
Never use anti-inflammatories without cage rest
Steroid use at all is controversial

28

IVD Extrusion - prognosis

Deep pain present? Yes: 90%
No? < 50%

29

Fibrocartilaginous embolic myelopathy (FCEM) - what is it?

Detachment of the IVD substance (nucleus pulposus) and lodging into a blood vessel - acute. Causes spinal cord ischemia due to the embolism in a spinal cord vessel
(thoracolumbar/cervical)

30

Fibrocartilaginous embolic myelopathy (FCEM) - breeds

Non-chondrodystrophic large breed dogs
Miniature schnauzers

31

Fibrocartilaginous embolic myelopathy (FCEM) - clinical signs

Acute / hyper acute onset
Non-progressive
Asymmetrical CS
Non-painful

32

Spinal cord arterial supply

10 pm, 2pm = upper spinal cord
6 pm = lower spinal cord

33

Fibrocartilaginous embolic myelopathy (FCEM) - diagnosis

History/clinical signs
Rule out others
MRI - Intramedullary, focal, asymmetrical

34

Fibrocartilaginous embolic myelopathy (FCEM) - treatment & recovery

Treatment = supportive
Recovery = may do well if still have deep pain & start to get some recovery within the first 2 weeks

35

Spinal trauma types

Endogenous (e.g. IVD Extrusion)
Exogenous (e.g. HBC)
(spinal cord contusion, vertebral fracture/luxation, traumatic IVD extrusion, hemorrhage)

36

How do you deal with a life-threatening trauma injury

1. Airway/Breathing/Circulation
2. Minimal manipulation
Physical/Orthopaedic exam
Brief neurological exam (latera recumbency, localize severity, deep pain)

37

Treatment for primary vs. secondary injury

primary: decompression/stabilization
secondary: maintenance spinal cord perfustion (BP, PO2), steroids?

38

Acute, progressive, T3-L3 myelopathy

1. IVD herniation/extrusion
2. Inflammatory/Infectious (GME, infectious, spinal empyema
3. Neoplasia
4. Less likely: Spinal trauma, FCEM, others

39

Differentials for hemiparesis, delayed proprioception on the same side, and decreased flexor reflex in the same side thoracic limb?

1. FCEM (Fibrocartilaginous embolic myelopathy)
2. IVD herniation (extrusion)
3. Others

40

Myelopathies - chronic (5)

IVD herniation - protrusion
Atlantoaxial subluxation
Degenerative myelopathy (Genetic degeneration of the spinal cord white matter mainly from T3-L3)
Caudal cervical spondylomyelopathy (wobbler's)
Degenerative lumbosacral stenosis

41

IVD herniation - protrusion: what is it?

A fibroid degeneration of the intact disc (hansen type II degenration); part of the normal aging process.
Progressive thickening on the dorsal annulus. A chronic, slow, compressive myelopathy

42

IVD herniation - protrusion: Signalment & Clinical signs

Chronic, progressive (weeks, years)
Non-chondrodystrophic large dogs (or any)
Age > 5 years old (5-12 years)
Cervical/thoracolumbar
Spinal pain is mild/moderate vs. none

43

IVD herniation - protrusion: Diagnosis

Spinal radiographys/myelogram
CT-myelogram
MRI

44

IVD herniation - protrusion: Treatment

Restrict activity
Anti-inflammatory drugs
Steroids (useful for chronic spinal cord injury e.g. predinsone
Many can be controlled for a long time

45

IVD herniation - protrusion: Surgical treatment - success rate, reasons

Less successful than IVD herniation - extrusion
Deterioration after surgery (temp or permanent), reperfusion injury
Lack of spinal cord functional reserve capacity: chronic compression, irreversible damage
(assume: Thoracic:
Hemilaminectomy
Pediculectomy
Cervical: Ventral Slot
Use surgical if pain or neurological deficits)

46

Atlantoaxial subluxation - what is it?

Instability between C1-C2
Dorsal displacement of C2 (causes spinal cord compression)
Congenital & acquired forms

47

Atlantoaxial subluxation - Clinical signs

C1-C5 myelopathy (can be chronic or acute)
progressive, severe neck pain, dyspnea

48

Atlantoaxial subluxation - Congenital form

Small toy canine breeds (yorkshire terrier, chihuahua, miniature schnauzer)
< 1 year old
Failure of ligament support or failure of C2 dens development (hypoplasia/absence/dorsal angulation)

49

Atlantoaxial subluxation - Acquired form

Traum -> acute; any dog/cat

50

Atlantoaxial subluxation - Diagnosis

Spinal radiographs (usually diagnostic)
Increased space dorsal lamina atlas - dorsal spinous process axis (C2)
Extreme care manipulation - better if awake patient
Myelogram, CT, MRI

51

Atlantoaxial subluxation - treatment

Stabilization +/- dens removal
High morbidity/mortality
Risk of respiratory arrest & death

52

Atlantoaxial subluxation - conservative treatment

Young animals with mild signs
External splint >= 6 weeks
Risk or recurrences

53

Degenerative myelopathy

Degeneration of the spinal cord white matter mainly from T3-L3 (genetic --> form of amyotrophic lateral sclerosis (ALS); genetic marker identified)
Pelvic limb ataxia, abnormal placement of the hind limbs, crossing over, reflexes are normal

54

Degenerative myelopathy - signalment

Large breed (german shepherd **, boxer, pembrokeshire welsh corgi, others
Age: > 5 years old (mean of 9)

55

Degenerative myelopathy - clinical signs

Chronic & progressive
T3 - L3 (severe pelvic limb proprioceptive ataxia, paraparesis/paraplegia, sometimes decreased patellar reflexes)
No spinal pain

56

Degenerative myelopathy - diagnosis

Rule-out other chronic T3-L3 myelopathies (IVD protrusion, neoplasia; normal spinal imagine)
Genetic marker present (DNA)
For a definitive diagnosis -> histopathology

57

Degenerative myelopathy - treatment & prognosis

Supportive/physical therapy
Vitamins/aminocaproic acid, steroids? (not proven)

Prognosis: poor -> euthanasia in 6-12 months (can progress to thoracic limbs if kept alive)

58

Caudal cervical spondylomyelopathy (CCSM)

Wobbler's syndrome (cervical stenotic myelopathy; cervical malformation/malarticulation)
Vertebral malformations/malarticulations affeting caudal cervical vertebrae & acssociated structures (liagments/facets/discs)
Deficits in the thoracic limbs may be less (at least initially) than the pelvic limbs

59

Caudal cervical spondylomyelopathy (CCSM) - pathogenesis

1. Malformation/malarticulation
2. Degenerative changes in the spine
- hypertrophic ligaments
- IVD protrusions (C5-C6, C6-C7)
- stenosis vertebral canal
- articular facets: DJD, cysts, hypertrophy
3. Spinal cord compression

60

Caudal cervical spondylomyelopathy (CCSM) - name the 2 forms

1. disc associated CCSM: large breed, middle aged 3-9 (IVD protrusion)
2. Osseous-associated CCSM. Giant breed (great dane) < 3 years old, articular facets DJD, canal stensosis

61

Caudal cervical spondylomyelopathy (CCSM) - clinical signs

Chronic, progressive
C6-T2 more likely than C1-C5
Tetraparesis (pelvic limbs much worse -> severe ataia & paresis); thoracic limbs (short, stilted, choppy gait -> hypometria)
Neck pain in 50% of cases

62

Caudal cervical spondylomyelopathy (CCSM) - diagnosis

Spinal radiographs
Myelogram
CT-myelogram
MRI (identifies intramedullary lesions)

63

Caudal cervical spondylomyelopathy (CCSM) - treatment -> conservative

Surgical treatment is usually recommended
Conservative therapy:
Restricted exercise; physical therapy;anti-inflammatories (steroids are beneficial in chronic spinal cord compression)

64

Caudal cervical spondylomyelopathy (CCSM) - treatment -> Surgical

None are very successful
1. Ventral approach: ventral slot; distration/stabilization; disc associated CCSM
2. Dorsal approach: dorsal laminectomy; osseous-associated CCSM; multiple ventral compressions (will deteriorate later)

65

Caudal cervical spondylomyelopathy (CCSM) - treatment -> Surgical prognosis

Surgical treatment - good 70-90% success
Recurrence rate >= 30%
can have domino-effect after surgical stabilization & long recovery period

66

Degenerative lumbosacral stenosis
(DLSS) - what is it?

Compression cauda equine nerve roots due to degenerative changes at L7-S1
(Cauda equine syndrome/lumbosacral malarticulation, lumbosacral instability/lumbosacral spondylopathy)

67

Degenerative lumbosacral stenosis
(DLSS) - pathogenesis?

1. Chronic instability
2. IVD protrusion between L7-S1
3. hypertrophy of the ligaments (interarcuaate-flavum) & articular facets (DJD, synovial cysts)
4. Subluxation of L7-S1

68

Degenerative lumbosacral stenosis
(DLSS) - signalment?

- large-breed dogs (german shepherds)
- middle aged to older
- males more likely than females (?)
LMN lesion caudal to L7 (Sciatic, pudendal, coccygeal)

69

Degenerative lumbosacral stenosis
(DLSS) - clinical signs

MAIN: Lumbosacral pain (reluctance to rise, sit, jump; lameness; PLs tucked under abdomen; low tail carriage)
Other clinical signs often not present

70

Degenerative lumbosacral stenosis
(DLSS) - what is it?

TBD

71

How do you detect lumbo-sacral pain?

Dorsal palpation of the LS joint, hyperextension PLs, raising up of tail, rectal palpation of the lumbosacral joint

72

What neurologic signs do you expect with a lower motor lesion caudal to L7?

Paraparesis (short-stride gait, not ataxia or mild)
Mild proprioceptive deficits (pelvic limbs)
Tail paralysis (low tail carriage)
Pelvic limb muscle atrophy (sciatic innervated)
Decreased withdrawal reflexes (hock)

73

Degenerative lumbosacral stenosis
(DLSS) - diagnosis?

Spinal radiographs
Myelogram (but spinal cord ends at L6 in large dogs)
Epidurogrpahy, discography
CT
MRI

74

Degenerative lumbosacral stenosis
(DLSS) - treatment?

Conservative: (if first episode & intermittent pain) -> restricted exercise, anti-inflammatory with success 70%

75

Degenerative lumbosacral stenosis
(DLSS) - prognosis?

Surgery requires >= 12 weeks of confinement
Recurrences are more likely in active working dogs.
If only pain - good to excellent
If motor deficits - good to guarded
If incontinence - guarded to poor

76

Spinal pain sources

1. Meninges
2. Nerve roots
3. Vertebrae & associated structures (periosteum, ligaments, joints, muscles)

77

Differentials for low head carriage, reluctance to walk, severe neck pain, pyrexic, lethargic, praying posture

1. Inflammatory / Infectious

78

Dyskospondylitis

Infectious disease in the spine & intervertibral disk & adjacent vertebrae.
Tends to be caused by bacteria more likely than fungal
Causes neck pain, systemic issues (fever, anorexia) and uncommonly neurological deficits
Can be diagnosed on spinal rads (CT/MRI)
Treatment is antibiotics (anti fungal, analgesics)

79

Steroid-responsive meningitis-
arteritis (SRMA) - what is it? signalment? diagnosis? treatment? prognosis?

A non-infectious, immune-mediated disease causing neutrophylic pleocytosis in the CSF, neck pain, pyrexia, lethargy, anorexia that can be diagnosed on CSF and treated with corticosteroids with a good outcome. 8-18 month-olds, boxer, beagles, bernese mountain dogs, german pointers.

80

3 types of peripheral nervous system or neuromuscular diseases

1. Peripheral nerve
2. Neuromuscular junction
3. skeletal muscle

81

How do you tell if there is peripheral nerve disease?

1. Reflexes are decreased or absent
2. Reduced or absent muscle tone
3. Neurogenic muscle atropic
Note: CNs can be affected

82

How do you tell if there is neuromuscular junction disease?

1. Reflectes are normal to decreased to absent
2. There is a diffuse clinical signs or focal
3. There can be exercise induced weakness (MG)
Note: CNs can be affected
(examples are myasthenia gravis, botulism)

83

How do you tell if there is muscle disease (myopathy)?

1. Reflexes are usually normal
2. Can be focal or diffuse (exercise intolerance)
3. Severe muscle atrophy
4. Muscle pain is possible
Note: CNS are usually normal (masticatory muscle atrophy)
(examples are polymyositis, masticatory muscle myositis)

84

Name some types of mononeuropathies

1. Traumatic (brachial plexus avulsion, radial nerve, sciatic nerve damage)
2. Neoplastic (peripheral nerve sheath tumour (PNST))
3. Others (Ischemic, neuromyopathy, foraminal IVDD, inflammatory - abscess, brachial plexus neuritis)