Sensory and Motor Deficit Cases

Question 1

Likely to be corticospinal and corticobulbar tract fibers below cortex and above medulla on the contralateral side

Answer 1

Unilateral face, arm, and leg weakness or paralysis with no associated sensory deficits

Question 2

Likely to be entire primary motor cortex, including face, arm, and leg representations of the precentral gyrus, or corticospinal and corticobulbar tract fibers above the medulla on the contralateral side

Answer 2

Unilateral face, arm, and leg weakness or paralysis with associated somatosensory, oculomotor, visual, or higher cortical deficits

Question 3

Likely to be arm and leg area of the motor cortex

Likely to be corticospinal tract from the lower medulla to the C5 level

• Motor cortex or medulla: contralateral side
• Below pyramidal decussation: ipsilateral
• Cortical lesions sparing the face usually affect proximal more than distal muscles
• Anterior cerebral or middle cerebral watershed infarct, lateral trauma, MS

Answer 3

Unilateral arm and leg weakness or paralysis

Question 4

Likely to be arm area of the primary motor cortex, on the contralateral: small cortical branch of the MCA

Likely to be peripheral nerves supplying the arm, ipsilateral: compression injury or diabetic neuropathy

Answer 4

Unilateral arm weakness or paralysis (brachial monoparesis)

Question 5

Likely to be leg area of the primary cortex (contralateral)

Likely to be lateral corticospinal tract below T1 (ipsilateral)

Likely to be Peripheral nerves supplying the leg (ipsilateral)

Answer 5

Unilateral leg weakness or paralysis

Question 6

Likely to be facial nerve (CN VII)

Answer 6

Unilateral facial weakness or paralysis: Bell’s palsy

Question 7

Likely to be genu of internal capsule or face area of primary motor cortex

Answer 7

Unilateral facial weakness or paralysis

Question 8

Face and arm areas of the primary motor cortex on the contralateral side

Answer 8

Unilateral face and arm weakness or paralysis

Question 9

Unilateral face and arm weakness or paralysis

Answer 9

Face and arm areas of the primary motor cortex on the contralateral side

Question 10

Unilateral facial weakness or paralysis

Answer 10

Likely to be genu of internal capsule or face area of primary motor cortex

Question 11

Unilateral facial weakness or paralysis: Bell’s palsy

Answer 11

Likely to be facial nerve (CN VII)

Question 12

Unilateral leg weakness or paralysis

Answer 12

Likely to be leg area of the primary cortex (contralateral)

Likely to be lateral corticospinal tract below T1 (ipsilateral)

Likely to be Peripheral nerves supplying the leg (ipsilateral)

Question 13

Unilateral arm weakness or paralysis (brachial monoparesis)

Answer 13

Likely to be arm area of the primary motor cortex, on the contralateral: small cortical branch of the MCA

Likely to be peripheral nerves supplying the arm, ipsilateral: compression injury or diabetic neuropathy

Question 14

Unilateral arm and leg weakness or paralysis

Answer 14

Likely to be arm and leg area of the motor cortex

Likely to be corticospinal tract from the lower medulla to the C5 level

• Motor cortex or medulla: contralateral side
• Below pyramidal decussation: ipsilateral
• Cortical lesions sparing the face usually affect proximal more than distal muscles
• Anterior cerebral or middle cerebral watershed infarct, lateral trauma, MS

Question 15

Unilateral face, arm, and leg weakness or paralysis with associated somatosensory, oculomotor, visual, or higher cortical deficits

Answer 15

Likely to be entire primary motor cortex, including face, arm, and leg representations of the precentral gyrus, or corticospinal and corticobulbar tract fibers above the medulla on the contralateral side

Question 16

Unilateral face, arm, and leg weakness or paralysis with no associated sensory deficits

Answer 16

Likely to be corticospinal and corticobulbar tract fibers below cortex and above medulla on the contralateral side