Neuro 60:Motorneuron disorders Flashcards
1
Q
4 Sx of upper motor neuron problems
A
- wkness and slowness of mvmnt
- increased tone (spasticity)
- hyperreflexia
- upgoing toes (Babinski’s sign)
* *everything UP
2
Q
5 Sx of lower motor neuron problems
A
- wkness on ipsilateral side
- decreased tone
- hyporeflexia
- muscle atrophy
- fasiculations and cramps –> due to abnormal NT release
* *everything LOWERED
3
Q
4 types of spinal muscular atrophy and when they typically present
A
- Type I (Werdnig-Hoffman) = before 6 mnths
- Type II = btwn 6 mnthss and 18 mnths
- Type III (Kugelberg-Welander) = after 18mnths
- Type IV = adult onset (30s or 40s), rarer
* *all are disorders of the anterior horn cells and only LMN are involved in these diseases
4
Q
Spinal muscular atrophy inheritance
A
- autosomal recessive
- due to homozygous deletion or point mutation in the SMN1 gene
- severity of phenotype is related to the number of copies of the SMN2 gene which is protective and can compensate for some of the mutations in SMN1
5
Q
Sx of Werdnig-Hoffman disease + life expectancy
A
- SMA type I
1. hypotonia + generalized wkness = floppy baby syndrome
2. tongue fasiculations –> usually present in most muscles, but most noticible here
3. abdominal breathing
4. weak cry
5. poor sucking
6. never sit - b/c so weak - only 8% live to 10 yrs
6
Q
Sx of SMA Type II + life expectancy
A
- intermediate form, onset is btwn 6-18mnths
1. can sit independently, but never walk
2. postural hand tremor
3. prone to kyphosis and joint contractures - b/c of poor tone
4. otherwise sx are similar to SMA I - *2/3rds survive to age 25
7
Q
Sx of Kuegelberg-Welander disease + life expectancy
A
- SMA III
- onset after 18mnths
1. walk and sit, but never run
2. 40% still walk at age 40
3. postural hand tremor - *life expectancy NOT affected by disease
8
Q
Amyotrophic lateral sclerosis (ALS) features
A
- AKA Lou Gehrig’s disease
- neurodegenerative disorder of the anterior horn cell
- loss of mn in the spinal chord, brainstem, and motor cortex –> so have LMN and UMN Sx
- etiology unknown, some cases are genetic, may have some envi causes, or triggered by trauma
9
Q
ALS presentation
A
- 2/3 of pts have limb onset of sx = wkness and wasting of distal limbs + fasiculations/cramps + NO sensory sx (painless)
- 1/3 of pt have bulbar onset = dysphagia, dysarthria, dysphonia, chewing difficulties
- no matter how the pt presents they usually develop resp wkness –> usually the cause of death
10
Q
ALS
A
- riluzole = NMDA receptor antagonist
- therapy = PT, OT, and Speech/swallowing
- resp mngmnt
- mngmnt of sx
11
Q
ALS prognosis
A
- median survival after onset = 24 - 36 mnths
- median survival after dx = 14-21 mnths
- 3 yr survival = 40%
- 5 yr survival = 25%
12
Q
4 common causes of degenerative nerve root disorders
A
- degerative disease of the spine
- disc herniation
- inflammatory or infectious diseases
- neoplasmic infiltrations
* *AKA radiculopathies
13
Q
Radiculopathy: sx + tx
A
- neck/back pain + mild sensory loss in distribution of nerve root (dermatome)
- wkness is RARE b/c of myotomal overlap
- tx: surgical or conservative
- can be self limiting
- can recur w/ time
14
Q
Causes of plexopathy
A
- trauma - birth trauma
- inflam/autoimmune
- neoplastic invasion
- radiation exposure
- structural anomalies
* *RARE
15
Q
Erb’s palsy
A
- upper trunk injury
- see wkness of proximal muscles and spared distal muscles = waiter’s tip phenom
- usually due to birth trauma from pulling on the babies head
