Hello and thank you for your question,
No, lacunar infarct cannot be caused by head trauma. Lacunar infarct happens when a tiny blood clot within an artery breaks off and travels down the artery to the point where it gets stuck. When it gets stuck and blocks blood flow, it causes the infarct.
Head traumas, either in motor vehicle or in other accidents, may cause a brain artery to rupture causing a bleed in the brain but it is different from the lacunar infarct.
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