Nutrient foramen

A nutrient foramen (plural: nutrient foramina) or vascular channel is a small tunnel through the cortex of a long bone containing a nutrient artery which supplies the bone.

The foramina are known to mimic oblique fractures on plain radiographs . The nutrient artery enters a long bone via an obliquely oriented canal, that can appear as a radiolucent line passing through the cortex into the medullary portion of the diaphysis of the bone. They are often observed with a well-corticated edge . The direction of the oblique canal is relative to the rate of growth occurring at both ends of the long bone .

Frequency

Although not all nutrient foramina will be visible in plain radiography, it is important to know the frequency in which they occur.

• majority of humeri possess a single nutrient foramen . However, humeri with two or no foramina have been reported
• up to 99% of radii have a single foramen , again with some studies cited two or none
• the ulna regularly presents with a single foramen, with as many as three cited in anatomical studies
• studies regarding the nutrient foramen of the femur range from one to as many as nine
• the tibia primarily possesses nutrient foramina on the posterior aspect of the diaphysis; with a single foramen most common
• the fibula most commonly possesses a single foramen however as many as three has been reported
• the phalanges typically possess a single foramen however the proximal phalanges of the fingers commonly have two, with all foramina directed away from the origin of bone growth