This anatomic study was performed on 25 disarticulated pelves and 10 embalmed cadavers to evaluate an anterior approach to the sacroiliac joint. The angle of inclination of the superior limb of the sacroiliac joint was 15 degrees superolateral to inferomedial in the sagittal plane, and the inferior limb was parallel to the sagittal plane. The cranial lateral part of the ala overlapped the joint space and the adjacent part of the ilium. Elevation of a rectangular bone block on the cranial part of the ala removed the joint space from the superior limb and provided direct access to the joint space of the inferior limb.