SA spinal column

how many cervical vertebraes are there

7

how many thoracic vertebrae are there

13

how many lumbar vertebrae are there

7

how many sacrum vertebrae are there

3

how many coccygeal vertebrae are there

20-23

what are the difference between cat and dog spinal columns in xrays

* cats have thing and long bones
* spinal column is long and rectangular
* dogs have very blocky spinal cords

what species is this

cat

is this a cat or dog xray

dog

which vertebraes dont have a intervertebral disk

C1-C2

what does C1 do

it moves the head around

and holds the neck muscles

what is another name for C1

atlas

what is this?

C1 Atlas

another word for dens

odontoid process

whats significant about dens

its holds C1 and C2 together and its a very important articulation

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identify the vertebrae

C2 axis

what is this part the arrow is pointing too

dens

CASE

* 8 month M yorkie mix
* progessive ataxia and weakness all 4 limbs
* knucking on all 4 limbs
* holds head down most of the time

hypoplastic dens

atlanto Axial subluxation

what is ataxia

incoordination

dont know where the legs are

describe what is going on here

Atlanto- Azial AA subluxation

* common in miniature and toy breeds
* dens malformations along with loss/weaking of ligamentous structures
* cervical pain and neurologic deficits

what does a normal xray of C1 and C2 look like

what are the ligaments of C2

* transverse ligament of atlas
* alar ligament
* apical ligament of dens
* nuchal ligament
* dorsal atlantoaxial ligament

what kind of picture is this and what is going on

MRI of AA subluxation

how to fix a AA subluxation

* surgery
* fuse c1 and c2
* recover full sensation
* cement it back in place

which cervical vertabrae is important for xray landmarks

C6

it has a large transverse process

how many cervical nerves are there

8

what is important about C6-T2

concentration of lower motor neurons=nerves of the brachial plexus

what are the main nerves of the brachial plexus

* suprascapular
* musculocutaneous
* axillary
* radial
* thoracodorsal
* median
* ulnar
* lateral thoracic

whats the main nerve that comes off L4-S1

femoral nerve

whats the main nerve that comes off S1-S3

sciatic

where would you collect cerebrospinal fluid

* cerebellomedullary cistern
* in between the occipital protuberance and wing of atlas

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describe thoracic vertebra

they have long spinal processes

t11 important why

also called anticlinical

its a landmark that tells u exactly where t11 is because the spinal process switches directions

what keeps t2 and t11 from getting disc disease

intercapital ligament

where is the dorsal longitudinal ligament

lies on the floor of the vertebral canal and runs from the dens to the sacrum

what vertebrae is the most common for disc disease

lumbar vertebrae

there is a lot of movement

What cant you see in a normal lumbar verterbrae xray

you cant see the spinal cord

where can you tap for cerebrospinal fluid in the lumbar region

in between L5 and L6

in the subarachnoid space

what is myelogram

where you stick contrast material to see the spinal cord

what are the differences between cervical and lumbar spinal canals

cervical spinal canal is much wider than the lumbar

where is the epidural space

L7 and S1

lumbosacral epidural

what are the four landmarks for an epidural

* ilial wings
* dorsal spinous process of L7
* sacral vertebrae

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where does the spinal cord end

L6-L7

what is cauda equina

caudally streaming spinal roots innervating pelvic viscera and tail

CASE

* 7yr Male Intact germnan shepherd- working dog
* decreased willingness to jump into truck
* low tail carriage
* difficulty posturing to defecate
* pain on palpation of the lower back and on tail lift

lumbosacral stenosis

cauda equina syndrome

* painful lower back/ tail
* L7-S1 damaged
* not the spinal cord its the spinal roots
* femoral nerve
* sciatic
* pudendal
* pelvic
* coccygeal

what is going on and what type of image is this

lumbosacral stenosis

cauda equina syndrome

mri bone=dark

fluid=light

what is the sacroiliac joint

bodies of the 3 sacral vertebrae fuse to form the sacrum

what are the sacral ligaments

1. dorsal sacroiliac ligament (also a ventral)
2. sacrotuberous ligament

what ligaments do cats not have

sacrotuberous ligament

label 1-4

1. dorsal sacroiliac ligament
2. sacrum
3. 1st coccygeal vertebrae
4. sacrotuberous ligament

what holds the ilium to the sacrum

sacroiliac ligament

CASE

* 4 yr Male intact chihuahua
* hit by car
* multiple laceration and unable to stand on his back legs

fractures on the weight bearing axis

* fractured pubis -preventing from walking
* fractured iscchium
* sacroiliac luxation -preventing from walking

put pins on the sacroiliac luxation and everything is shifted back

where is it common for vertebraes to fuse

common in the cervical region

increases the risk of intervertebral disk disease

bulldogs, frenchies are at greater risk for this

what are hemivertebrae

* failure of the development and ossification of part of a vertebrae
* usually a vertebral body
* can lead to compression of the spinal cord
* french bulldogs, pugs, bulldogs
* not a fuse

what is a transitional vertebrae

when something is not supposed to be there

but its not a bad thing

CASE

* 2yr male english bulldog
* chronic skin irritation around his tail
* moist dermatitis
* painful to tock and clean

* screw tail


* malformation of one to several vertebrae in the tail
* most common in bulldogs
* you amputate tail

what is significant about manx cats

* dominant mode of inheritance- homozygous is lethal
* abnormal development of the sacral and coccygeal vertebrae
* “manx syndrome” some cats have no problems vs severe neurologic conditions

identify

nucleaus pulposus

annulus fibrosis

1. annulus fibrosis
2. nucleus pulposus

CASE

* 4 yr MN dachshund
* jumped off the couch and screamed in pain
* lost motor function in both hind legs
* can feel but not move

intervertebral disc disease

describe intervertebral disc disease

* dachshunds and other “chondrodystophic” breeds predisposed
* nucleus pulposus dehydrates and becomes dry and brittle
* risk of traumatic extrusion into the spinal cord

what is a hemilaminectomy

spine surgery that involves removing parts of one of the two laiminae on a vertebra to relieve excess pressure on the spinal nerves in the lumbar spine