Sacrum, Coccyx, & SI Joints: Radiographic Anatomy - Video Lesson

Hey, everybody. Welcome to today's lesson on radiographic anatomy, demonstrated on routine projections of the sacrum, coccyx, and sacroiliac joints. In a previous lesson, we discussed the anatomy of these structures and which radiographic projections are routinely performed. So let's tie that information to the radiographs themselves. As a reminder, the routine radiographic projections of the sacrum and coccyx are apiaxial and lateral, and the routine radiographic projections of the SI joints are apiaxial and apiaobliques. Take a look at this radiograph. What projection is being demonstrated? How do you know? Let's find out the answers to these questions. If you said this radiograph is an AP axial projection of the sacrum, you're correct. In this image, the sacrum, SI joints, and l five through s one intervertebral joint space are demonstrated. It is a true AP because there is alignment of the median sagittal crest and coccyx with the symphysis pubis.