RLE motor and sensory loss with medial frontal syndrome (mutism/akinetic) and transcortical motor aphasia with poor retrieval. Which stroke territory best explains this presentation?

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An anterior cerebral artery (ACA) territory stroke best fits this presentation. The ACA supplies the medial surfaces of the frontal lobes, including the paracentral lobule that controls the contralateral leg. When this area is damaged, you see weakness and sensory loss primarily in the leg on the opposite side, which matches the right leg involvement here. Medial frontal damage also produces a medial frontal syndrome with abulia and, in more pronounced cases, mutism or akinetic mutism due to disruption of circuits in the supplementary motor area and anterior cingulate.

If the dominant (left) hemisphere is affected, these frontal regions are also linked to language initiation networks. That explains the transcortical motor aphasia pattern—nonfluent speech with retrieval difficulties, but with relatively preserved repetition because the arcuate fasciculus is spared and the language output is initiated from nearby frontal systems. Putting all this together, left ACA stroke accounts for the right leg motor/sensory findings, the mutism/akinetic frontal syndrome, and the transcortical motor aphasia with poor retrieval.

In contrast, left MCA stroke would typically produce broader cortical language deficits and more arm/face involvement; right ACA stroke would cause left leg signs and abulia but not aphasia; right MCA inferior stroke would produce neglect and language changes if the dominant side were involved, which doesn’t align with the medial frontal mutism and transcortical motor aphasia pattern seen here.