UMN

Question 1

How would UMN lesion causing facial weakness present?

Answer 1

Unilateral lesion: Contralateral lower face weakness - can’t smile etc but can still raise eyebrows. Little effect on speech

Bilateral lesion: all muscles paralysed. Preserved emotional expression. Major difficulty producing labial and labiodental sounds

Question 2

How would LMN lesion causing facial weakness present and what is this condition called?

Answer 2

Bell’s palsy

IPSILATERAL weakness of upper and lower face

loss taste ant 2/3 tongue, hyperacusis, decreased or absent lacrimation, positive synkinesis test (voluntary muscle movement causes simultaneous involuntary contraction of other muscles)

Question 3

Name 11 anatomical levels/sites at which a UMN lesion may occur.

Answer 3

1. Motor cortex
2. Corona radiata
3. Internal capsule
4. Midbrain
5. Pons
6. Medulla
7. Spinal cord
8. Bulbar tract
9. Lower motorneuron tract
10. Corticospinal tract
11. Corticobulbar tract to brainstem.

Question 4

Where is the lesion if dense hemiplegia of acute onset involving arm, leg, face

Answer 4

UMN
Most probably lesion of posterior limb of internal capsule (secondary to occlusion of deep penetrating lat lenticulo-striate aa for eg)
Or basal pons (eg occlusion of paramedic penetrating aa)

Question 5

What are the 2 most prevalent pathologies in the internal capsule?

Answer 5

Lacunar infarcts (<15 mm size, secondary to lipohyalinosis of penetrating a)
Haemorrhages

Question 6

Hemiplegia is pathopneumonic for which lesion?

Answer 6

UMN

Question 7

Hemiparesis of acute onset with arm weaker than legs favours which lesion?

Answer 7

UMN- middle cerebral artery

Question 8

Hemiparesis of acute onset with leg weaker than arm - where is lesion?

Answer 8

Anterior cerebral artery (umn)

Question 9

Dense hemiplegia with hemisensory deficit and homonymous hemianopia- where is lesion?

Answer 9

Internal capsule

Question 10

Monoparesis - where is lesion

Answer 10

Localised to motor cortex (umn)

Cortical branch occlusion syndrome secondary to cerebral a embolism affecting a distal cerebral a branch.

Question 11

Spastic paraparesis- where is lesion?

Answer 11

Spinal cord at thoracic/cervical level

Question 12

What is cortical paraplegia

Answer 12

Bilateral medial motor cortex lesions, with confusion or other cerebral symptoms

Question 13

6 causes of cortical paraplegia

Answer 13

1. CP
2. Parafalx meningioma
3. Butterfly astrocytoma of corpus callosum
4. Sagittal sinus thrombosis
5. Anterior Communicans artery aneurysm with spasm of both ant cerebral arteries
6. Prox ant cerebral a stem occlusion

Question 14

Where is lesion in spastic quadriplegia usually

Answer 14

Cervical spinal cord

Question 15

What is crossed hemiplegia

Answer 15

Ipsilateral UMN signs arm, contralateral leg

Question 16

How do lesions at lower level of medulla oblongata (cranio-cervical junction) (at crossing of corticospinal tracts) typically present? (2)

Answer 16

Crossed hemiplegia

Characteristic pattern of progression of umn weakness eg ipsilat arm then leg weak, then contralat arm then leg weak.

Question 17

What is Brown Sequard syndrome

Answer 17

Hemi-section of spinal cord

Question 18

How does Brown Sequard syndrome present? (3)

Answer 18

Umn weakness ipsilat - corticospinal
Dorsal column signs ipsilat (proprioception, vibration, fine touch)
Spinothalamic signs contralat below lesion (pain and temp )

= hemisection

Question 19

What is Weber syndrome? (3)

Answer 19

Caused by a lesion (stroke circumferential a) in 1/2 midbrain medial aspect cerebral peduncle,
resulting in ipsilat CNIII palsy and contralat hemiplegia

Question 20

What is Millard- Gübler syndrome?

Answer 20

Lesion (stroke circumferential a) of basal lower 1/3 medial pons causing 
contralat hemiplegia (corticospinal tract), ipsilat CN VI, VII! palsy

Question 21

What is locked-in syndrome? (7)

Answer 21

Bilat infarction ventral central pons with or without medulla involve, causing quadriplegic paralysis and mute but still conscious (intact brainstem RF) . Pts can often move eyes vertical (not horiz) due to CN III and IV sparing in midbrain.
May be pseudobulbar palsy. Bilat facial weak
Secondary to pontine myelinolysis, glioma, tuberculoma

Question 22

How does lesion of medulla oblongata present? (2)

Answer 22

Contralateral hemiplegia (crossing of corticospinal tract occurs caudally)
Ipsilat CN xii paralysis may be found in Hughlings- Jackson syndrome

Question 23

How would acute stroke in mid pons present? (2)

Answer 23

Ipsilat CN V motor paralysis

Contralat hemiplegia

Question 24

Name 5 features UMN lesson

Answer 24

• No wasting, maybe minimal disuse atrophy or contractures
• increased tone
• “pyramidal” pattern of weakness (extensors weaker than flexors in arms, flexors weaker than extensors in legs)
• increased reflexes, clonus
• babinski sign (extensor plantar response)

Question 25

Name 2 alternatives to babinski reflex

Answer 25

• Chaddock reflex: stroke from lateral malleoulus to small toe
• oppenheim: anterior tibia

Question 26

Name 6 causes rigidity

Answer 26

• Parkinson’s
• Catatonia
• extrapyramidal symptoms of antipsychotics (haloperidol)
• neuroleptic malignant syndrome
• tetanus
• tardive dyskinesia

Question 27

Name 5 causes spasticity

Answer 27

• Cortical lesion: stroke
• spinal injury: myelopathies, trauma
• multiple sclerosis
• cerebral palsy
• neurogenerative disease affecting UMN, pyramidal and extrapyramidal pathways

Question 28

Name 3 broad causes of stroke in young people

Answer 28

• Embolic causes eg afib
• vessel wall disease eg HIV
• hypercoagulability eg antiphospholipid antibody syndrome