 Sacroiliac joint dysfunction is a source of low back pain that causes significant pain and disability. Injection of the sacroiliac joint with a local anestheticcorticosteroid mixture has shown efficacy in treating this condition, when conservative therapy fails. The use of fluoroscopic guidance and anatomic landmarks are traditional methods for performing this injection; however, ultrasound imaging has recently been utilized for performing this procedure. Although studies exist that describe and validate the ultrasound technique, no studies exist that compare the techniques with respect to short-term and long-term outcomes. In this study, the primary objective is to determine if a difference exists between a fluoroscopic-guided technique and ultrasound-guided technique with respect to pain and function. A secondary objective is to compare the two techniques with respect to procedural characteristics. 