DeLahunta Chapter 10 - Small Animal Spinal cord disease

Question 1

Which are the most common conditions causing central cord syndrome according to Ros et al., 2022 for dogs? Where was the most common site a;ected. What factor was associated with poor outcome?

Answer 1

The most common was intervertebral disc extrusion Hansen type I, and hydrated nucleus pulposus extrusion. The most common site affected was C3/4, C4/C5. Hypoventilation was 14.7 times more likely to have poor outcome.

Question 2

Which are the most common conditions causing central cord syndrome according to Ros et al., 2024 for cats? And which region in the spinal cord?
https://avmajournals.avma.org/view/journals/javma/262/3/javma.23.08.0478.xml

Answer 2

Two neuroanatomical localizations were associated with CCS: C1-C5 spinal cord segments in 17 (77.3%) cats and C6-T2 spinal cord segments in 5 (22.7%) cats. Neuroanatomical localization did not correlate with lesion location on MRI in 8 (36.3%) cats. The most common lesion location within the vertebral column was over the C2 and C4 vertebral bodies in 6 (27.2%) and 5 (22.7%) cats, respectively. Peracute clinical signs were observed in 11 (50%) cats, acute in 1 (4.5%), subacute in 4 (18%), and chronic and progressive signs were seen in 6 (40.9%) cats. The most common peracute condition was ischemic myelopathy in 8 (36.3%) cats, whereas neoplasia was the most frequently identified chronic etiology occurring in 5 (22.7%) cats. Outcome was poor in 13 (59%) cats, consisting of 4 of 11 (36.6%) of the peracute cases, 3 of 4 (75%) of the subacute cases, and 6 of 6 of the chronic cases.

Question 3

Why the Schiff-Sherrington syndrome occur? Please explain the mechanism behind it? In which spinal cord segments is the lesion typically located?

Answer 3

Grey matter L1-L5 spinal cord segments. Dysinhibition due to sudden loss of the axons in a long interneuronal pathway that originates from neuronal cell bodies primarily in the grey matter. These interneurons are referred to as border cells because they are located in the dorsolateral border of the ventral gray column of the lumbar spinal cord segments. Tei axons course cranially in the fasciculus proprius and terminate by synapsing on thoracic limb extensor LMN in the cervical intumescence.

Question 4

Which neurotransmitter is considered to contribute to the pathophysiology of
spinal shock?

Answer 4

Inhibitory neurotransmitter glycine

Question 5

Please state MRI diferences between iscaemic myelopathy caused by FCE and ANNPE in dogs?

https://pmc.ncbi.nlm.nih.gov/articles/PMC4672181/

Answer 5

FCE: focal, relatively sharply demarcated intramedullary and often lateralizing but can be bilateral lesion, grey matter being hyperintense on T2W and FLAIR, iso- or hypo to normal grey matter on T1w. T1W may show contrast enhancement on the 5th to 7ths day of the disease.

ANNPE: focal hyperintensity, lateralized on t2W of the spinal cord overlying an intervertebral disc space with absent or minimal spinal cord compression. T1w iso with no evidence of contrast enhancement. Decreased size and signal intensity of the affected nucleus pulposus on T2w images and the ivd is often narrowed. Epidural material might be evident.

Question 6

What is the survival of nephroblastoma with cytoreductive surgery and radiotherapy versus palliative. Which spinal cord segment is this tumor most commonly located? Which is the most common compartment of the spinal cord that nephroblastoma affects?

Answer 6

1) Located T10-L2.
2) inradural/extramedullary
3) Dogs treated with cytoreductive surgery (n=6) or radiotherapy (1) survived longer (median, 374 days; range, 226–560 days) than dogs treated palliatively (3; median, 55 days; range, 38–176 days).

Question 7

Please state infectious agents which could cause dyscospondylitis.

Answer 7

Staphylococcus pseudointermedius, Streptococcus species, E coli, Brucella canis, Aspergillus spp. (German Shepherd), Salmonella

Question 8

Based on Durand et al., 2022, which regions of the spinal cord were most
commonly a;ected by lymphoma in cats? Which other body systems can be
found to be a;ected in these cats?
https://onlinelibrary.wiley.com/doi/full/10.1111/jvim.16350

Answer 8

conus medullaris and lumbosacral plexuses, bone marrow and kidney

Question 9

In disseminated idiopathic skeletal hyperostosis: DeDecker 2014
a)Which breed and anatomical structure are commonly affected?
b) . How many consecutive vertebrae need to be affected to be considered as
such?

Answer 9

ossification of the ventral longitudinal ligament underneath the vertebrae of the spinal cord - develop bone marrow - same intensity as vertebral body
Boxer
at least 4 consequitive vertebra

Question 10

In AAI,
a. Which pathologic mechanism leading to dens absence is proposed by delahunta?
b. According to Pilkington 2024 et al
i. Which per centage of patients with juvenile myelopathy presented with atlantoaxial
instability?

Answer 10

De Lahunta proposes that a progressive degeneration of the dens
(similar as leg-parthes syndrome) rather than an agenesis could explain the
bone defects observed. As a proper agenesis would involve the whole
ossification centrum 1 of the axis with different morphological findings as
well as onset of disease.
a) 8%

Question 11

Name the common breed, age of presentation, most common clinical signs and
CNS histopathological changes associated with Inherited Encephalomyelopathy
and Polyneuropathy.

Answer 11

Rottweiler
b. 6-8 weeks of age
c. Inspiratory dyspnea and paraparesis, progressing to tetraparesis +/-
regurgitation and microphthalmia.
d. Bialteral symmetrical primary axonopathy with secondary demyelination and
astrogliosis affecting lateral and ventral spinal cord funiculi.

Question 12

According to Lopes et al, which was the most common diagnosis found in
patients with cranial thoracic myelopathy?
https://www.frontiersin.org/journals/veterinary-science/articles/10.3389/fvets.2022.960912/full

Answer 12

Neoplasia

Question 13

According to Fenn et al; which were the most common breeds diagnosed with
ANNPE & ischemic myelopathy? Which were the most common SCS affected in
these breeds?

https://avmajournals.avma.org/view/journals/javma/249/7/javma.249.7.767.xml

Answer 13

English Staffordshire Bull Terriers for ischaemic L4-S3
Border Collies for ANNPE C1-C5

Question 14

In Petersen et al, which was the most common localisation for spinal
meningiomas in dogs?

https://pubmed.ncbi.nlm.nih.gov/18482277/

Answer 14

Cervical region (68%) - most of them at the level or cranial to C3 vertebral
body

Question 15

In Globoid cell leukodystrophy; mention:
a. The common breeds affected:
b. The usual age of presentation:
c. Common neurological findings:
d. According Bradbury 2016 which other pre-mortem tests can be performed
on top of PCR on a patient with suspicion of GCL https://pmc.ncbi.nlm.nih.gov/articles/PMC5027978/pdf/nihms798491.pdf

Answer 15

a) WHWT and Cairn Terriers
b) 3-7m
c)cerebellar ataxia, GP ataxia and paresis
progressing to recumbency, dementia and blindness.
d) MRI, nerve conduction
velocity, BAER, Psycosine levels in CSF.

Question 16

Which are the reported MRI features associated with SRMA in dogs according to
Ramelli et al and Jones et al?
https://www.frontiersin.org/journals/veterinary-science/articles/10.3389/fvets.2022.957278/full

https://onlinelibrary.wiley.com/doi/10.1111/jsap.13775?af=R

Answer 16

Ramelli et al:
Meningeal enhancement: 80%
b. Articular process synovial joint enhancement: 65%
c. Paravertebral muscle enhancement: 55%
d. Nerve root enhancement: 30%

Jones et al. 2024:
paravertebral muscle changes (30/53; 56.6%), meningeal contrast enhancement (13/41; 31.7%)
- spinal cord parenchymal T2-W hyperintensity (15/53; 28.3%). Haemorrhage was observed in five of 53 (9.4%) cases – three intradural-extramedullary, one intramedullary and one extradural. Following binary logistic regressions, T2-W spinal cord parenchymal hyperintensity had a significant positive association with paresis/paralysis (odds ratio 14.86, 95% confidence interval 1.42 to 154.99) as did haemorrhage (odds ratio 16.12, confidence interval 2.05 to 126.73).

Question 17

Which proportion of non-traumatic haemorrhagic myelopathy were associated
with SRMA?
https://pmc.ncbi.nlm.nih.gov/articles/PMC10229319/

Answer 17

%13

but second most common reason (1st angio)

Question 18

Which are the ligaments of a-a joint?

Answer 18

1) 1 transverse ligament (holds the dens dorsally in contact with caudal articular fovea of atlas and cranial articular surface of axis)
2) 1 apical ligament
3) 2 alar ligaments
(2 and 3 attach the apex of dens to basioccipital bone)
4) dorsal atlantoaxial dliagment (thick one between dorsal arch of atlas and spine of axis)

Question 19

State 8 inherited neuro disorders of Rottweilers

Answer 19

1) neuroaxonal dystrophy
2) polyneuropathy (axonopathy)
3) duchene muscular dystrophy
4) MPS 1
5) distal neuropathy
6) motor neuron disease
7) leukoencephalomyelopahty
8) inherited encephalomyelopathy and polyneuropathy

Question 20

What does it mean central cord syndrome?

Answer 20

When the TL are more affected, because in caudocervical lesion when the grey matter or C1-C5 scs tracts closer to the grey matter are affected – central cord syndrome. Tracts that are UMN pathways. AA-subluxation can do this.

Question 21

What is spinal shock?

Answer 21

Is a paradoxic LMN-like pelvic limb sign in a patient with UMN pathway interruption represent spinal shock. The reduced patellar reflex is observed only for a few hours, but the hypotonia may persist for 10-14 days. The pathomechanism would imply accumulation of glycine.

Question 22

In which breeds FCE can appear?

Answer 22

Miniature Schnauzer, Boxer, Labrador retriever, as young as 3 months of age. Source of embolus – degenerated disc, which occludes artery, vein or even venous plexus. In young dogs the source could be the vertebral growth plate.

Question 23

In which productive animal FCE can happen at young age and why?

Answer 23

pigs during transportation
vertebral growth plates - source of embolus

Question 24

How can you diagnose Distemper virus infection in dogs?

Answer 24

Serology, PCR, CSF. Immunofluorescence antibody testing, inclusion bodies may be seen in conjunctival swabs or in blood leukocytes in acute cases.

Question 25

Which breed can be predisposed for discospondylitis? What is the pathomechanism?

Answer 25

The Airedale terrier, because they have a low serum IgA, high serum of beta 1 globulins and blastogenesis supressing factors.

Question 26

What is the difference in multiple cartilaginous exostosis different between dogs and cats?

Answer 26

dogs–> disease of young until the normal growth plates are finished
in cats–> disease after sketetaly mature

Question 27

In which breed degenerative myelopathy can occur? What clinical sign is important? Which genetic mutation is responsible for this condition?

Answer 27

GSD, CKCS, Pembroke Welsh Corgi, Kuvatz, Bernese mountain dog
SOD 1 - exon 1 for all
SOD 1 -exon 2 for Bernese

Question 28

What is caused by hypervitaminosis A?

Answer 28

In cats this can be caused by diet that contains high level of vitamin A, raw liver, which secondarily may cause development of extensive bone proliferation related to synovial joints. Naurological signs can cause discomfort, nerve entrapment at intervertebral foramina or myeloathy

Question 29

MRI versus radiographic appearance of the AA subluxation.

Answer 29

On MRI T2W hyperintensity caused by gliosis and atrophy. Also dorsalmdisplacement of the cranial articular surface of the axis.

On radiographs there is increased space between the dorsal arch of the atlas and the spinous process of the axis, which appears to project dorsally and to be displaced caudally. In lateral radiographs we can notice lack of dens.

Question 30

In which location is calcinosis circumscripta more common?

Answer 30

Atlato-occipital and atlanto-axial calcinosis.

Question 31

Breeds predisposed for SRMA.

Answer 31

Boxer, Bernese mountain dog, Golden retriever, Nova Scotia duck tolling retriever

Question 32

What is the origin of neprhoblastoma? Which are its components histologically? Which age of dogs affects? Which is its common locations?

Answer 32

mesodermal origin (mesonephric)

1) sheet of unorganised epithelial cells (blastemal cells)
2) tubular elements lined by epithelial cells (some of which have glomelural strucutre)

Younger than 3.5yo

T10-L2 SCS

Intradural-extramedullary

Question 33

The most common infectious cause of disko in dogs?

Answer 33

Staph.pseudointermedius

Question 34

What are the timings of the ossicification in dog’s atlas and axis bones?

Answer 34

1) centrum 2 of axis (3m)
2) centrum of proatlas (3-4m)
3) intercentrul 1 of atlas and intercentrum 2 of axis (4m)
4) centrum 1 of atlas and caudal epiphysis of axis (7-9m)

Question 35

Why respiration can be compromised in a patient with AAI?

Answer 35

transverse injury interefers with reticulospinal tracts –> necessary for respiration at that level

Question 36

What is the genetic mutation for Globoid cell leukodystrophy in dots?

Answer 36

GALC Gene