Lec 29 Motor System Clinical Correlations Flashcards
(37 cards)
Do you get spasticity in UMN or LMN lesion?
UMN
What is typicall distribution of weakness in upper motor neuron lesion?
in upper extremities: flexors stronger than extensors
in lower extremities: extensors are stronger than flexors
look at shoes: adductors stronger than abductors –> outside may be more worn
Do you see babinski [big doe upgoing] in UMN or LMN lesion?
in UMN lesions
What are some examples of UMN lesions?
cerebrovascular accident [stroke], intracranial tumor, cervical spine injury
What are some examples of LMN lesions?
motor neuron disease, peripheral nerve neuropathy, polio, spinal cord injury resulting in nerve root compression
What is normal reflex on the scale?
2+ is normal
What is normal muscle strength on the scale?
5
3 = against gravity
What is hemiplegic gait?
- arm in flexion with weakness of extensors of fingers/wrist
- hand and fingers tightly clenched
- outward swing of leg
- reduced arm swing
what is spastic gait?
- both legs stick, have toe walking
- walking slow and stiff
- bilateral
- hyperreflexia
what is frontal [magnetic] gait?
- difficulty getting out of chair and finding center of gravity
- small steps as if feet stuck to ground
What disease is frontal [magnetic] gait associated with?
seen in normal pressure hydrocephalus –> on exam usually cognitive impairment
What is amyotrophic lateral sclerosis?
combined anterior horn + pyramidal tract disease = UMN and LMN
- no sensory, cognitive, or oculomotor deficits
characterized by: rapid progressive weakness, muscle atrophy and fasciculations, muscle spasticity, difficulty speaking, difficulty swallowing, difficulty breathing
Causes of ALS?
can be due to defect in superoxide dismutase 1
What are 2 viruses that can affect anterior horn?
- polio
- west nile
What is treatment for ALS?
riluzole [prolongs survival 2-3 mo]
prognosis = 3-5 years
What are other disease that might present like ALS? how do you determine ALS?
- determine ALS by demonstrating disease above foramen magnum [ex. dysarthria, swallowing disorder, jaw jerk]
otherwise could be: tumor of brainstem or cervical spondylosis
What is primary lateral sclerosis?
- UMN, no LMN involvement
- lesion of motor cortex
- slowly progressive spastic quadriparesis
what is progressive spinal muscular atrophy?
- LMN, no UMN involvement
- weakness, wasting, fasciculations with variable age onset
What is cervical spondylosis?
can be UMN and LMN involvement
but no involvement above foramen magnum
What presentation in a lesion of motor cortex?
- UMN disease
ex. primary lateral sclerosis
what presentation in a lesion of internal capsule?
- contralateral motor or sensory deficit
What presentation in a lesion of brainstem?
- ipsilateral cranial nerve deficits + contralateral motor deficits
- jaw jerk reflex impaired
what presentation in an anterior horn spinal cord injury?
- LMN disease = ipsilateral weakness, atrophy, fasciculations, hyporeflexia
- absence of cognitive or sensory changes
ex. spinal muscular atrophy, polio, west nile
what presentation in peripheral neuropathy?
- distal weakness [longest nerves first]
- steppage gate [LMN leg weakness]
- foot drop
- weakness/hyporeflexia
