L07: Neurolocalization (Carrera) Flashcards
UMN signs**
Normal or increased reflexes
increase in tone
paresis to paralysis
weak and stiff
LMN signs**
loss of reflexes
loss of tone
paresis to paralysis
weak and floppy
Brain signs
behavior changes CN deficits seizures CP deficits ataxia paresis
forebrain includes:
cerebrum, diencephalon
brainstem includes:
midbrain, pons, medulla oblongata
brain includes
forebrain
cerebellum
brainstem
individual cranial nerves
where does cn 1 exit?
cerebrum
where does cn 2 exit?
diencephalon
which cn come out of midbrain?
3,4
which cn come out of pons?
5
which cn come out of cerebellum?
none
which cn come out of medulla oblongata
6-12
FOREBRAIN signs
seizures circling compulsion behavior change (ie. stick in corner) blindness postural reaction deficits normal gait
If pupillary light reflex pathways intact but still can’t see, where is lesion?
Cortex
4 CS of Horner’s Syndrome in dogs***
loss of sympathetic innervation –>
1) ptosis (drooping eyelid)
2) prolapsed 3rd eyelid
3) miosis (pupil constriction)
4) enophthalmos (posterior displacement of eyeball)
CS of Horner’s Syndrome in horses
- eyelashes point down
- unilateral sweating (on affected side)
- inc. temp of face/neck/shoulder –> vasodilation
Cerebellum lesion signs
head tilt nystagmus (involuntary eye movement) loss of menace intention tremors truncal sway ataxia hypermetric, spastic gait NO paresis, behavior changes, CP deficits
Brainstem lesion signs
decreased mentation (stupor, comatose) CN deficits usually cn8 involvement --> nystagmus tetraparesis CP deficits ataxia
how to localize spinal cord lesion
1) presence of myelopathy and change in postural reactions
2) segmental reflexes help you localize it
C1-C5, C6-T2, T3-L3, L4-S3
muscle tone: extended, difficult to flex limb implies:
UMN lesion
muscle tone: flaccid, unable to support any weight implies:
LMN involvement, spinal shock
C1-5 lesions will have what TL/PL postural reactions?
dec. to absent in TL and PL
C6-T2 lesions will have what TL/PL postural reactions?
variable TL, dec. to absent PL
T3-L3 lesions will have what TL/PL postural reactions?
N TL, dec. to absent PL
L4-S3 lesions will have what TL/PL postural reactions?
N TL, variable PL
motor unit nerve lesions will have what TL/PL postural reactions?
N to dec. TL and PL
NMJ lesions will have what TL/PL postural reactions?
N TL and PL
muscle lesions will have what TL/PL postural reactions?
N TL and PL
C1-C5 lesion signs
\+/- ambulatory -knuckling, stumbling, face-planting -tetraparesis -ataxia (uncoordinated movement) worse in PL -N to inc. reflexes in all limbs \+/- muscle fasiculations, pain
C6-T2 lesion signs
\+/- ambulatory -knuckling, stumbling, face-planting -"two-engine" gait -tetraparesis -ataxia -reflexes N to dec. in TL, N to inc. in PL \+/- m. fasiculations, pain
T3-L3 lesion signs
\+/- ambulatory -paraparesis -PL ataxia -hunched \+/- pain, panniculus cut-off, Schiff-Sherrington posture -reflexes N in TL, N to inc. in PL
Schiff-Sherrington posture
- extensor hypertonia of the TLs due to loss of ascending inhibition
- assoc. with severe TL lesions
- NOT diagnostic!
- must distinguish from decerebrate posture
L4-S3 lesion signs
\+/- ambulatory, pain, panniculus cut-off PL ataxia paraparesis (PL) N reflexes in TL dec. to absent reflexes in PL \+/- anal tone, tail tone/sensation, perineal reflex
LMN lesion signs
\+/- ambulatory, facial n. weakness, gag reflex NO ataxia, pain Paresis (generalized) dec. to absent reflexes exercise intolerance
IVDD can be acute progressive/non-progressive, or chronic progressive
:)
painful spinal lesions***
IVDD meningitis/meningomyelitis diskospondylitis fracture/luxation neoplasia (bone) *there are no nerve endings within the cord!*
