Our knowledge of the vascularization of the precentral gyrus by branches of the anterior
cerebral artery (ACA) relies mainly on anatomical cadaveric dissection. A distal branch of the
ACA known as the posterior internal frontal artery (PIFA) is thought to vascularize the precentral
gyrus responsible for proximal arm movement; however, no clinical correlation has yet been reported
to confirm this relation. In this manuscript, we report a case of coil migration in the PIFA, causing
proximal arm weakness in a 58-year-old woman treated for aneurysmal subarachnoid hemorrhage.
The occurrence of clinical signs immediately following coil migration into the PIFA, combined
with evidence of stroke in the cortical territory related to arm movement as seen on imaging,
indicates that the PIFA indeed can vascularize this lateral portion of the precentral gyrus. This case
confirms our current understanding of the vascularization of the precentral gyrus by distal ACA
branches, in particular the PIFA.