The sacroiliac joints reside between the sacrum (the tailbone phase with the spinal column) as well as the well known wing-like iliac bones that variety the pelvic girdle. There are 2 SI joints, one to the still left and a person on the proper (highlighted in red from the picture https://fronthippaintreatment47899.laowaiblog.com/33170717/the-basic-principles-of-front-hip-pain-treatment