"location: pelvis"
"origin: from the posterior division of the internal iliac artery in the pelvis"
"branches: superior and inferior sacral arteries"
"branches: superior and inferior sacral arteries"
"supply: sacral meninges, piriformis muscle, erector spinae muscles, cutaneous area over sacrum"
"The superior branch passes medially, often anastomoses with the middle sacral artery and enters S1 and S2 foramina. It enters and supplies the sacral meninges and exits posteriorly to supply erector spinae and the cutaneous area over the sacrum, and anastomoses with the superior gluteal artery."
"The inferior branch passes inferomedially over the piriformis muscle and runs down toward the coccyx, where it anastomoses with the middle sacral artery. It passes through the S3 and S4 foramina to supply spinal meninges and exits to supply muscle and overlying skin posteriorly."