Direct measurements of the nutrient foramen of thirty dried ilia using digital calipers and observations of the nutrient a. from ten cadaveric specimens were made in the present study. The nutrient foramen was situated 12.5 +/- 2.7 mm lateral to the anterosuperior sacroiliac joint line but perpendicular to this line and 23.5 +/- 5.8 mm above the pelvic brim parallel to the sacroiliac joint line. The nutrient a. originated from the iliolumbar a. as it coursed across the anterosuperior aspect of the sacroiliac joint. The present anatomic study indicates that the nutrient a. on the internal surface of the ilium is prone to injury as a result of traumatic disruption of the sacroiliac joint, sacral alar fractures and during the anterior approach to the sacroiliac joint.