A patient presents with pure motor hemiplegia of the right arm and leg without sensory, speech, or visual deficits. MRI reveals a small infarct. Where is the most likely location?

• A Posterior limb of internal capsule on the left ✓
• B Left precentral gyrus (motor cortex)
• C Left pontine basis (paramedian)
• D Left medullary pyramid

Explanation

The posterior limb of the internal capsule (PLIC) contains the densely packed corticospinal and corticobulbar fibers for the contralateral body within a small area, making it the classic site for a lacunar infarct producing pure motor hemiplegia. Motor cortex lesions (option B) typically produce focal, somatotopically graded weakness. Pontine basis lesions may produce additional cranial nerve signs. Medullary pyramid lesions are rare and would produce a Babinski but rarely cause this pure pattern without tongue weakness.

Reference: BD Chaurasia's Human Anatomy, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.