Umn & Lmn Lesions

Question 1

1. Which condition is most likely to present with hyperreflexia?
   a) Poliomyelitis b) Diabetic neuropathy c) Upper motor neuron lesion d) Botulism

Answer 1

c) Upper motor neuron lesion

Question 2

2. A positive Babinski sign in an adult indicates:
   a) Lower motor neuron lesion b) Upper motor neuron lesion c) Normal reflex d) Peripheral neuropathy

Answer 2

b) Upper motor neuron lesion

Question 3

3. Flaccid paralysis is a hallmark of:
   a) Stroke b) UMN lesions c) LMN lesions d) Multiple sclerosis

Answer 3

c) LMN lesions

Question 4

4. Fasciculations are most commonly seen in:
   a) UMN lesions b) LMN lesions c) Both UMN and LMN lesions d) Neither

Answer 4

b) LMN lesions

Question 5

5. Spasticity is characterized by:
   a) Rigidity b) Hypertonia c) Hyporeflexia d) Weakness

Answer 5

b) Hypertonia

Question 6

6. The clasp-knife phenomenon is associated with:
   a) Spasticity b) Rigidity c) Hypotonia d) Flaccidity

Answer 6

a) Spasticity

Question 7

7. Which of the following reflexes is absent in LMN lesions?
   a) Babinski sign b) Pronator drift c) Deep tendon reflexes (DTRs) d) Hoffman’s sign

Answer 7

c) Deep tendon reflexes (DTRs)

Question 8

8. The pronator drift test primarily assesses:
   a) Muscle strength b) UMN function c) LMN function d) Proprioception

Answer 8

b) UMN function

Question 9

9. Damage to the corticospinal tract results in:
   a) Spastic paralysis b) Flaccid paralysis c) Fasciculations d) Loss of proprioception

Answer 9

a) Spastic paralysis

Question 10

10. Which of the following is a characteristic feature of rigidity?
    a) Velocity-dependent resistance b) Lead-pipe rigidity c) Hypotonia d) Clasp-knife phenomenon

Answer 10

b) Lead-pipe rigidity

Question 11

11. Which type of atrophy is more severe, with up to 70-80% muscle mass loss?
    a) Denervation atrophy b) Disuse atrophy c) Both are equally severe d) Neither causes atrophy

Answer 11

a) Denervation atrophy

Question 12

12. Which special test involves flicking the middle finger to assess for UMN damage?
    a) Pronator drift b) Babinski sign c) Hoffman’s sign d) Clonus test

Answer 12

c) Hoffman’s sign

Question 13

13. What is the physiological mechanism of the positive Babinski sign?
    a) Decreased inhibition of dorsiflexors b) Hyperactivation of plantar flexors c) Inhibition of Type Ia fibers d) Increased Ach release

Answer 13

a) Decreased inhibition of dorsiflexors

Question 14

14. Which muscle group shows fasciculations in LMN lesions?
    a) Intrinsic hand muscles b) Tongue muscles c) Quadriceps d) Facial muscles

Answer 14

b) Tongue muscles

Question 15

15. A lesion affecting both alpha and gamma motor neurons would result in:
    a) Spastic paralysis b) Hyperreflexia c) Flaccid paralysis d) Tremors

Answer 15

c) Flaccid paralysis

Question 16

16. Which UMN pathway is involved in voluntary movement of cranial nerves?
    a) Corticospinal tract b) Corticobulbar tract c) Reticulospinal tract d) Vestibulospinal tract

Answer 16

b) Corticobulbar tract

Question 17

17. Hyperreflexia observed in UMN lesions is primarily due to:
    a) Increased gamma motor neuron activity b) Loss of inhibitory signals to the spinal cord c) Increased alpha motor neuron activity d) Decreased Ach release

Answer 17

b) Loss of inhibitory signals to the spinal cord

Question 18

18. Which finding differentiates spasticity from rigidity?
    a) Rigidity is velocity-independent b) Spasticity is associated with tremors c) Both conditions involve hypotonia d) Rigidity affects reflexes

Answer 18

a) Rigidity is velocity-independent

Question 19

19. Denervation atrophy occurs in LMN lesions due to:
    a) Decreased Ach at the neuromuscular junction b) Decreased Type Ia fiber sensitivity c) Increased proteolysis and reduced protein synthesis d) Disruption of the corticospinal tract

Answer 19

c) Increased proteolysis and reduced protein synthesis

Question 20

20. A lesion to the corticobulbar tract affecting CN VII would result in:
    a) Complete facial paralysis b) Contralateral lower face weakness c) Ipsilateral lower face weakness d) Loss of taste

Answer 20

b) Contralateral lower face weakness

Question 21

Where is the lesion in a 35-year-old man with sudden onset of left-sided facial droop, inability to wrinkle forehead, close eye, or smile on the left side, and diminished taste sensation on the anterior two-thirds of the tongue?

Answer 21

LMN lesion of the facial nerve - Bell’s palsy

Question 22

What is the lesion type and location in a 50-year-old woman with right-sided facial weakness that spares her forehead and normal reflexes?

Answer 22

UMN lesion - Left corticobulbar tract

Question 23

What is the most likely diagnosis for a patient with sharp, stabbing pain on the left side of their face triggered by light touch near their cheek, following the distribution of the maxillary division of the trigeminal nerve?

Answer 23

Trigeminal neuralgia - Maxillary division (CN V2)

Question 24

Where is the lesion in a 60-year-old woman with reduced corneal reflex on the left side, normal sensation in the left face, but paralysis of the left orbicularis oculi?

Answer 24

LMN lesion of the facial nerve - Zygomatic branch

Question 25

Which nerve is affected in a patient with loss of sensation over the chin, difficulty chewing, and jaw deviation toward the left side when opening the mouth?

Answer 25

LMN lesion of the left mandibular division (CN V3)

Question 26

Where is the lesion most likely located in a 40-year-old woman with tearing and loss of taste sensation in the anterior two-thirds of her tongue but no facial weakness?

Answer 26

Greater petrosal nerve and chorda tympani - Facial nerve

Question 27

Which nerve is affected in a 72-year-old man with left-sided hemifacial spasm and MRI revealing a vascular loop compressing a cranial nerve?

Answer 27

Facial nerve (CN VII) - Hemifacial spasm

Question 28

Where is the lesion in a patient with complete facial paralysis on the right side, hyperacusis, reduced salivation, and absent taste on the anterior two-thirds of the tongue?

Answer 28

Proximal lesion of the facial nerve before the chorda tympani

Question 29

Which nerve is involved in a 45-year-old patient with anesthesia in the forehead, cornea, and nose on the left side, and absent corneal reflex bilaterally when touching the left eye?

Answer 29

Ophthalmic division of the trigeminal nerve (CN V1)

Question 30

Which nerve is most likely affected in a 30-year-old man with difficulty swallowing, a hoarse voice, and deviation of the uvula to the right?

Answer 30

LMN lesion of the left vagus nerve (CN X)