Upgrade to remove ads
Only $2.99/month

ataxia and incoardination

Terms in this set (36)

def
1. Ataxia is incoardination of voluntary motor activity in the absence of motor weakness
2. it is caused by cerebellar, sensory or vestibular disorders
3. ataxia can effect eye movement, speech, individual limbs, the trunk, or gait
types of ataxia
1. cerebellar ataxia
2. sensory (proprioceptive) ataxia
3. vestibular
4. mixed
5. psychogenic
6. false
cerebellar ataxia there are 2 syndromes
1. neocerebellar S
2. archicerebellar S
neocerebellar S
- is seen w lesions of the cerebellar hemispheres
- cerebellar hemisphere is responsible for coordination of movement and maintain tone in the ipsilateral limbs. So, disorders affecting one hemisphere => 1. ipsilateral hemiataxia, 2.hypotonia, 3. nystagmus, 4. dysarthria
1. hypotonia dt?
c/p?
- loss of facilitatory movement of the neocerebellum upon the stretch reflex.
- a) dec resistance to passive movement
b) Rebound phenomena: when the pt outstretches his arms and one of them is tapped unexpectedly, it swings over a wider rangenh than N.
c) change in deep tendon jerks, hypotonia might => dec reflexes, pendular jerk (is BEST seen w the knee jerk and it elicited legs hanging from bed side, it produce a series of oscilatory movement of leg)
2. incoardination of the movement (ataxia) dt?
-loss of the coordinating influence of the neocerebellum on the motor cortex while carrying-out voluntary movements
a) incoardination of the arm movement
tests?
signs?
-finger to nose test or finger to finger test
- 1) decomposition of the movement
2) dysmetria (hyper or hypometria)
3) kinetic tremor / action
4) dysdia-do-cho-kinesis
b) incoardination of the leg movement
test?
- heel-knee shin test
c) incoardination of the movement in gait
-unilateral cerebellar lesion=
-bilateral cerebellar lesion=
- severe cases=
- walking along a straight line (.... .... ....), in unilateral lesion there is deviation toward the ..... side.
- tends to deviate to the diseased side
- ataxic (drunken) gait, pt walk irregularly and staggering from one side to other
- unable neither to stand nor to walk
- toes to heel, diseased
3. eye movement (nystagmus)
dt?
- intention tremors of the extraocular ms
4) articulatory movements
dysparthria dt?
called?
-decompesation of the movements of articulation.
- scanning or staccato speech
B) archicerebellar S
dt?
@ by?
- lesions of the vermis, M/C with tumours
- 1. disturbance in the equilibirium (trunkal ataxia)
2. nystagmus
3. oscillation of the head (titubation)
4. no disturbance of the tone
5. pt while lying down in bed shows no manifestation and N coordinated limb movements. on getting up, there is difficulty in keeping balance while standing or walking, stand on a wide base, swaying f one side to other side and may fall in any direction
etiology of cerebellar ataxia
1) acute onset ataxia
- vascular: cerebellar infaction or hge. vertebrobasilar insufficiency
- traumatic
- demyelination: MS, Miller Fischer S
- Toxic: alcohol intake
- drug induced: phenytoin, hypnotic-sedative
- infection (varicella infection)
- wernicke's encephalopathy
etiology of cerebellar ataxia
2) chronic ataxia
- hereditary ataxia
- neoplastic: medulablastoma
- paraneoplastic (subacute cerebellar degeneration)
- MS
- phenytoin induced cerebellar degeneration
- infection: AIDS and syphilis
- slow virus infection : Creu-tz-feld-t Jakob dis
etiology of cerebellar ataxia
3) episodic (recurrent) ataxia
- transient ischemic attack
- basilar migraine
- inheritated intermittent ataxia
sensory (proprioceptive) ataxia
-sensory ataxia -> disorders that affect the proprioceptive pathways in peripheral sensory nerves, sensory roots, post colums of the spinal cord, or medial lemnisci
- thalamic or parietal lobe lesions are rare causes of sensory ataxia.
c/p for sensory ataxia
- joint position sense is impaired in the legs, mb defective in the arms.
testing by asking the pt to detect passive movement of the joints, beginning distally and moving proximally to establish the upper level of deficit in each limb.

-vibration sense is frequently impaired,
- steppage gait (lifting the feet high off the ground and stapping them down heavily)
-kinetic tremors (finger to nose or finger to finger tests appear ONLY on closure of the eyes)
- hyporeflexia of the legs (prominent in tabes dorsalis and polyneuropathies that cause sensory ataxia)
- nystagmus or dysarthria or vertigo are ABSENT
- +ve romberg's sign
causes of sensory ataxia
- peripheral neuropathies
- post root lesion eg. tabes dorsalis
- lesions in the post. column eg. Freidriech's ataxia, subacute combined degeneration of the spinal cord (B12 deficiency), MS.
- brain stem lesion (medial lemniscus): tumors
- lat nucleus of thalamus (thalamic S) eg: vascular lesion
vestibular ataxia
dt?
lesion of the vestibular syatem. vestibular ataxia results f the same central and peripheral lesions that cause vertigo
- periphersl vestibular lesions affect the labyrinth of the inner ear or the vestibular division of the acoustic VIII nerve
- central lesions affects the brain stem vestibulaar nuclei or their connections
c/p in vestibular ataxia
-nystagmus is frequent, typically unilateral and M/ prominent on gaze away f the side of vestibular involvement
- vestibular ataxia is gravity dependant= incoardination of limb movement cannot be demostrated when the patient is examined lying down but becomes apparent when the pt attemps to stand or walk.
- dysarthria does not occur
- vertigo is Dx
- mb tinnitus or deafness dt ass cohclear nerve affection
- eg: Meniere's dis. labrynthinis, acoustic neuroma
mixed ataxia
more than clinical types
- cerebellar and sensory ataxia -> MS, Friedriech's ataxia
- cerebellar &vestibular -> post. inf. cerebellar artery occlusion, acoustic neuroma
psychogenic ataxia
- mostly young age. more in girls, with historionic personality
* there is +ve angle-> history of stress
* negative angle -> no signs of organic disease, but patient presented with bizzar symptoms and signs
false ataxia
incoardination of the movement dt the presence of weakness or involuntary movement (e.g: chorea)
hereditary ataxias
they are a group of inherited disorders @ by?
1. usually hereditary and familial
2. clinically the M/I feature is ataxia which is usually cerebellar (but may be mixed cerebellar and sensory)
3. the onset is insidious and the course is slowly progressive (being degenerative process)
etiology of hereditary ataxias?
1) early onset forms: are transmitted by recessive inheritance. they include Fried-reich's ataxia, and a less common variant in which reflexes in the arms and at the knees are N or increased
2) late-onset forms: can be divided clinically into autosomal dominant cerebellar ataxia (ADCA) types I,II and III.
Friedreich's ataxia pathology
- the degeration is present in the spinal cord affecting 1) spino-cerebellar tract 2) pyramidal tracts 3) posterior columns 4)posterior roots, particularly in lumbosacral segments, deformities of the skeleton.
1) mani of slowly prigressive cerebellar ataxia
- it starts in the LL when the parent notices that the child walks on a wide base, tends to stagger and cannot run w other children at play
- as the cond advances, he might not able to walk w/o support
- later the movements of the upper LL become ataxic,
w acction tremors
- ossilation of the head (titubation) are common cerebellar ataxia at the level of the cranial nerves produce dysarthria & nystagmus
2) manif of corticospinal tract lesion
- weakness is most marked in the LLs w loss of abdominal reflexes and extensir plantars
- tone mb increased or dec depending upon whether pyramidal or spinocerebellar tracts are more affected
3. ankle jerk and mb the knee jerks are.....
loss bcause the lower roots (lumbosacral) are usually more affected
4. manifes of post column dysfunction
produce impairment of joint sense and vibration sense.
this adds an element of sensory ataxia w + ve rombergism
5. other mani
1. skeletal deformities (kyphoscoliosis & pes cavus)
2. cardiomyopathy
3. visual impairment (optic atrophy)
4. nystagmus
5. parasthesias
6. hearing loss
7. vertigo
8. clinically overt DM
9. cognitive deficiency
ddx
1. other types of idiopathic cerebellar degeneration
2. vit E def
3. ataxia telangiectasia
4. phenytoin-induced cerebellar degeneration
5. alcoholic cerebellar degeneration
6. wilson's disease
7. post fossa tumour
8. paraneoplastic cerebellar degenerations
9. disseminated sclerosis
px
eurological dysfunction typically => the inability to walk unaided within 5 years after the onset of symptoms and in a bed ridden state within 10-20 years.
ix
atrophy of the cervical soinalcord & sometimes also of tge cerebellum mb apparent on CT or MRI
tx
- no tx can influence the course of the dis
- orthopedic procedures such as tenotomy may help to correcr foot defirmities
- encourage tge pt to remain on his feet as long as possible
autosomal dominant cerebellar ataxia (ADCA)
1) ADCA type 1
ataxia is accompanied by opthalmoplegia, optic atrophy, dementia & pyramidal features
2) ADCA type II
ataxia is ass w pigmentary retinopathy w or w/o ophthalmoplegia and extrapyramidal features
3) ADCA type III
produce pure ataxia w/o extrcerebellar manif
THIS SET IS OFTEN IN FOLDERS WITH...