Sacro-iliac joint pain can be understood as a case of “broken pelvis” — in which the “break” occurs at the three major joints (syndesmoses) of the pelvis: at the pubic bone (pubic symphysis) and the two sacro-iliac joints. The break consists not of a fracture of bone, but as a displacement (misalignment) of the bones and as a strain at the joints.
My hypothesis, which fits experience, is that with displacement comes distortion of pelvic shape, registered as ligamentous strains within the pelvis that, when sensed by the brain, triggers muscular spasms not just in the pelvis, but as far-away as the neck and jaws.
The first step to correct S-I joint pain is to determine the misalignment. Two two major possibilities are a rotation and a displacement of one side downward; they generally occur together.
This tutorial clip shows what to look for to determine what the displacement is.
Full regimen: click here