PDF - Weakness

Question 1

What are the LMN signs?

Answer 1

1. Focal weakness
2. Prominent muscle atrophy
3. Decreased muscle stretch reflexes and tone
4. Fasciculations

Question 2

What causes LMN signs?

Answer 2

Lesions occurring anywhere along length of spinal cord or brain stem lower motor neurons

Question 3

What does involvement of a single peripheral nerve cause?

Answer 3

1. LMN signs
2. Sensory impairment confined to anatomical territory
3. Painful paresthesia or dysesthesia

Question 4

How does f peripheral neuropathy or polyneuropathy manifest?

Answer 4

Distal limb LMN signs and sensory (“stocking and glove”) loss, typically beginning in lower limbs

Question 5

How does radiculopathy present?

Answer 5

Neck or back pain which radiates into a limb or trunk in a dermatomal distribution, along which tingling or numbness may also occur

Question 6

How do Anterior horn cell lesions manifest?

Answer 6

weakness in a distal or proximal segment of a limb, eventually becoming more widespread and bilateral with prominent fasciculations in amyotrophic lateral sclerosis

Question 7

Pain seen in anterior horn cell lesions?

Answer 7

No

Question 8

UMN signs?

Answer 8

1. Diffuse weakness
2. Less muscle atrophy
3. Hyperreflexia
4. Spasticity
5. Babinski signs
6. Hemiparesis or hemiplegia

Question 9

How does hemiplegia from brain stem lesion present?

Answer 9

Hemiplegia accompanied by facial weakness, dysarthria, or dysphagia

Question 10

How does subcortical lesion in internal capsule or corona radiata present?

Answer 10

1. Hemiplegia
2. Relatively equal weakness in the contralateral lower
   face and upper and lower limbs

Question 11

How does Hemiplegia from a cortical lesion present?

Answer 11

Unequal weakness between affected upper and lower limbs

Question 12

What causes Hemiplegia with leg weaker than face and arm?

Answer 12

Lesion in more medial (parasagittal) portion of contralateral motor cortex
- Causes by occlusion of ACA

Question 13

What causes Hemiplegia w/ face and arm weaker than leg?

Answer 13

Lesion in more lateral portion of contralateral motor cortex

- Caused by an occlusion of MCA

Question 14

Which part of motor cortex does PCA perfuse?

Answer 14

None

Question 15

What does bulbar refer to? CN found here? Presentation?

Answer 15

The “bulb” or lower brain stem

• The fifth, seventh, ninth, tenth or twelfth CNs
• Weakness of chewing, speaking or swallowing
• LMN signs manifest as atrophy and fasciculations of muscles of face, jaws, palate or tongue

Question 16

What does weakness lacking LMN or UMN signs suggest?

Answer 16

Disorder of muscle or NMJ

- Sensation is preserved

Question 17

Lesion where causes slowness and clumsiness?

Answer 17

Extrapyramidal system (primarily basal ganglia) or cerebellar system

Question 18

What is cerebellum important for?

Answer 18

1. Balance

2. Smoothness and coordination of movement

Question 19

What do basal ganglia control?

Answer 19

1. Postural control
2. Muscle tone
3. More “automatic” types of movement