The sacroiliac joints are joints on the left and right side of the body between the sacrum (part of the spine) and the pelvis. People with pain here will complain of pain in the back, groin or hip. Injection to these joints with fluoroscopic guidance can be performed to improve pain. If the injection helps, but does not last, a rhizotomy or radiofrequency ablation can be performed for this joint. This procedure is used to give 9-12 months of relief at a time. When it wears off, the procedure may be repeated.