THE ARTERIAL SUPPLY OF THE HUMAN SACRUM AND COCCYX——EXTRA- OSSEOUS PART / 解剖学报

ABSTRACT

The arterial supply of the human sacrum and coccyx was studied on 56 fresh. cadavers of different ages by dissection, clearing, casting and radiography.All sacrums receive their blood supply from the lateral sacral arteries, the median sacral artery, the iliolumbar arteries and the fifth lumbar arteries. The median sacral artery, the lateral sacral arteries and their branches anastomose with each other and form the lattice anastomosis on the ventral surface of the sacrum.The anterior spinal canal branch bifurcates into an ascending and a descending branches. The former passes upwards to join the descending branch from the anterior spinal canal branch above it, they also anastomose with their contralateral counterparts, thus forming a rhombic system notable for its regularity.The posterior spinal canal branch also divides into an ascending and a descending branches and they join each other to dispose in a ladder anastomosis on the ventral surface of the laminae.The dorsal branch gives off three main sets of branches the lateral, the medial and the muscular. The medial and the lateral branches both subdivide into an ascending and a descending branches and they anastomose with each other on the dorsal aspect of the sacrum.On the ventral surface, the coccyx obtains arterial supply from the median sacral artery and the lateral sacral arteries, while its dorsal surface mainly receives blood supply of the lateral sacral artery. Anastomosis has been found scarce on the ventral and dorsal surfaces of the coccyx.