Nutrient artery of radius

The nutrient artery of the radius is a branch of the radial artery (or, in some descriptions, the anterior interosseous artery) that constitutes the principal blood supply to the diaphysis (shaft) of the radius bone.

The nutrient artery enters the radius through the nutrient foramen, located on the anterior to anteromedial surface of the bone in the second proximal quarter of the diaphysis — that is, between approximately 25% and 50% of the total bone length measured from the proximal end. The canal is directed obliquely, typically oriented proximally (toward the elbow), following the general rule that in the forearm, nutrient foramina are directed away from the growing end (the distal epiphysis being the primary growth center of the radius). Once the artery penetrates the cortex through the nutrient canal, it enters the medullary cavity and divides into ascending and descending branches.

Intraosseous Distribution

Within the medullary cavity, the nutrient artery branches into smaller arteries and arterioles that supply the bone marrow, the inner two-thirds of the cortex (endosteal supply), and the metaphyseal regions. These intramedullary branches terminate in capillaries at the metaphysis and endosteum, connecting with the broader intraosseous vascular network. The nutrient artery provides the dominant centrifugal blood flow pattern in the diaphyseal cortex, complemented by the centripetal supply from periosteal arteries on the outer bone surface.