Traumatic carotid artery dissection and occlusion caused by repetitive mechanical stress to the neck while carrying a mikoshi (portable shrine): illustrative case.

backgroundTraumatic carotid artery dissection can be caused by mechanical stress to the neck. The authors present a case of carotid artery dissection and occlusion caused by repetitive mechanical stress to the neck while carrying a portable shrine (mikoshi) during a traditional Japanese festival. OBSERVATIONS: A 41-year-old man with no significant medical history developed right hemiparesis and global aphasia while carrying a mikoshi during a festival. Imaging revealed left internal carotid artery occlusion, for which he underwent endovascular treatment. Because the occlusion was caused by dissection, carotid artery stenting was performed. The patient supported the mikoshi's carrying pole by tilting his neck to the left and clamping it between his neck and shoulder. He repeatedly bounced the mikoshi up and down on his left shoulder while carrying it, which likely caused repetitive mechanical stress to the carotid artery, ultimately resulting in dissection and occlusion. LESSONS: Carrying something on the shoulder can cause carotid artery dissection and occlusion. Therefore, care should be taken to avoid placing continuous mechanical stress on the neck while carrying objects. https://thejns.org/doi/10.3171/CASE25488.